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[Display omitted] • Mo(VI), W(VI), and Se(IV) significantly affect DAMO archaeal activity. • Orthogonal experiment reveals optimal micronutrient composition that enhances DAMO. • Long-term SBR with optimized medium increases nitrate removal rate by 1.5 times. • Abundances of DAMO archaea and mcrA gene elevate with micronutrient optimization. Metallic micronutrients play a crucial role in regulating the activity of microorganisms. Denitrifying anaerobic methane oxidation (DAMO) archaea possess all the canonical enzymes analogous to those involved in methanogenesis, which is notably rich in metalloenzymes. However, the relationship between metallic micronutrients and DAMO archaeal activity remains unexplored. Here we investigated the effect of micronutrients (Fe(II), Co(Ⅱ), Ni(Ⅱ), Zn(Ⅱ), Se(Ⅳ), W(Ⅵ) and Mo(Ⅵ)) on the DAMO archaeal activity. Batch assays indicated that among these micronutrients, Mo(Ⅵ), W(Ⅵ) and Se(Ⅳ) had a significant impact on DAMO archaeal activity, whereas the others showed minimal effects within their respective concentration ranges. Notably, the optimal concentrations of Mo(Ⅵ), W(Ⅵ) and Se(Ⅳ) substantially boosted DAMO archaeal activity, increasing nitrate conversion rates by 2.1, 1.45, and 1.84 times, respectively, compared to the rates at their lowest concentrations. An orthogonal experiment further confirmed the significant impact of Se(Ⅳ) and identified an optimal micronutrients composition. Subsequent long-term operation of a sequencing batch reactor (SBR) with this optimized medium demonstrated substantial improvements in DAMO performance. Specially, the nitrate removal rate increased to approximately 1.5 times higher than that of the original medium, and the nitrate consumption rate reached 1.98 mmol·d−1. In addition, microbial analysis indicated that both the abundance of Candidatus Methanoperedens and the key functional gene mcrA increased by 1.26 and 2.52 times, respectively, compared to that operated with the original medium, suggesting that the optimized medium enhanced both the metabolic activity and growth of DAMO archaea. These results underscore the pivotal role of micronutrients in modulating DAMO archaeal activity, thereby offering valuable insights for optimizing the DAMO process and advancing its practical application. [ABSTRACT FROM AUTHOR]

[Display omitted] • Solid-state fermentation (SSF) to produce biostimulant and biopesticide was studied. • SSF was carried out at bench scale using green waste and Trichoderma harzianum. • The production of biostimulant at bench-scale was higher than that at lab-scale. • Porosity is one of the basic indicators of a successful SSF at bench-scale. • Sequential batch experiment was conducted as a strategy to scale up the production. This study aimed to develop a bench-scale process of solid-state fermentation (SSF) to produce biostimulants (indole-3-acetic acid-IAA) by Trichoderma harzianum CECT 2929, utilizing green waste as substrate. Additionally, biopesticide activity (in form of conidial spores) was also studied. The SSF was carried out in a 22-L packed bed reactor using grass clippings as the main substrate and pruning waste or wood chips as bulking agent. When using pruning waste, IAA production reached 62 µg/g dry matter, while the fermentation with wood chips resulted in a higher IAA concentration of 120 µg/g dry matter. Higher spore counts were reached using wood chips (9.5 × 108 and 1.3 × 109 spores g−1 dry matter, respectively). Further experiments showed that decreasing tryptophan as precursor for IAA production from 0.43 % to 0.2 % (w/w) significantly decreased IAA production from 120 to 25 µg/g dry matter while it did not alter spore production. In addition, a sequential batch operational strategy was explored, consisting of four consecutive batches as a strategy to scale-up the SSF process. The highest IAA and spore productions were achieved in the first batch, resulting in 119 µg/g dry matter and 1.1 × 109 spores g−1 dry matter, respectively. Subsequent batches showed a decline in production, particularly in batches 3 and 4, due to contamination issues. Summarizing, the strategies proposed in this study are a considerable advance to develop SSF to produce biostimulant and biopesticide agents in the context of circular bioeconomy, using green waste as raw material. [ABSTRACT FROM AUTHOR]

• Metabolic coupling limits strain degeneration in continuous and repetitive batch cultures. • Positive feedback loops stabilize productive cells over revertant populations under strong coupling. • Optimal dilution rate and coupling mitigate strain degeneration in continuous bioreactors. • Strain degeneration is controlled by metabolic stress and reward, influencing large-scale productivity. • Bistability and hysteresis behavior allow shifts between productive and non-productive populations. Metabolic engineering involves the manipulation of multiple genes from different sources to produce desired compounds. Engineered cells typically suffer from metabolic effects associated with product accumulation resulting in abortive production phenotype or strain degeneration. The revertant cells post a major barrier for repetitive or continuous culture, lowering both productivity and cost-efficiency of large-scale fermentation. Herein we formulated a set of kinetic models to reveal the population dynamics of strain degeneration in batch and continuous culture. By introducing a dimensionless metabolic coupling coefficient, we analyzed the effects of metabolic stress and reward on strain performance. Only limited metabolic coupling effect was found in batch culture, nevertheless, metabolic reward can significantly enrich the productive population and alleviates strain degeneration in repetitive batch culture. In continuous bioreactors, metabolic coupling strength and dilution rate synergistically dictate the productive and abortive strain population. The region where productive population is dominant is characterized by a critical metabolic coupling coefficient and tipping dilution rate. We identified a metabolic-reward mediated positive feedback loop with bistability and hysteresis behavior which allows the productive cell outcompetes the abortive population, even under strong competitive exclusion. Our results emphasize the theoretical basis to engineer product-rewarded growth to suppress mutation and stabilize long-term strain performance, which should be adopted as a general guideline to deploy strain engineering strategies. [ABSTRACT FROM AUTHOR]

[Display omitted] • The feasibility of PAO enrichment (16 % abundance) in marine sediment was achieved. • EBPR can be performed in both sediment- and sludge-seeded SBRs fed with propionate. • Lack of LPO may prevent successful EBPR when fed glucose. • Excessive COD feeding at 400 mg/L led to GAOs outcompeting PAOs. • EBPR could enable P mining from sediment, with theoretical recovery rate > 94 % To evaluate the feasibility of enriching polyphosphate-accumulating organisms (PAOs) within marine sediment for achieving phosphorus (P) recovery, two sediment-inoculated sequencing batch reactors (SBRs), fed with propionic acid (R1) and glucose (R2), were operated for 119 days. For comparison, two sewage sludge-inoculated reactors (R3 and R4) were also set up. The sediments/sludge fed with 200 mg/L chemical oxygen demand (COD) equivalent propionic acid exhibited satisfactory P release/uptake performance after 56 days of culture. The maximum P release and uptake rates for R1 were 3 mg P/g VSS•h−1 and 2.5 mg P/g VSS•h−1, respectively, while for R3 they were 2.6 mg P/g VSS•h−1 and 5.8 mg P/g VSS•h−1, respectively. Meanwhile, the PAO family (Rhodocyclaceae) in R1 increased from almost 0 % initially to 16.0 % after 42 days. However, the glucose-fed SBRs did not exhibit enhanced biological phosphorus removal (EBPR) performance throughout the operation. As the COD feeding concentration increased to 400 mg/L, the reactors showed EBPR deterioration. Total P in R1 and R3 significantly decreased from 423.7 mg to 307.2 mg and from 368.0 mg to 94.9 mg, respectively. Key intracellular polymer responses indicated that introduction of excessively high COD significantly reduced poly-P content and the anaerobic synthesis of polyhydroxyalkanoate. Microbial analysis suggested that the breakdown of EBPR performance could be attributed to glycogen-accumulating organisms outcompeting PAOs under high carbon feeding conditions. Additionally, PHREEQC simulations confirmed that P-rich supernatant from the anaerobic phase could theoretically be recovered as struvite, with a recovery efficiency of up to 94 %. [ABSTRACT FROM AUTHOR]

[Display omitted] • The SPNAD system treating STHP-AD filtrate effectively facilitates PN recovery. • Nitrtosomonas was enriched (0.36 %→3.43 %), while Nitrospira was successfully inhibited (0.06 %). • PN facilitates effective enrichment of Candidatus Brocadia on biofilm (1.41%). • PN/A in intermittent aeration reducing aeration energy consumption while enhancing NRE by 20%. • The SPNAD achieve a NLR of 0.43 kgN/(m3·d) with an NRE of 78.66%. Currently, partial nitrification (PN) processes are commonly used to improve efficiency in high ammonia nitrogen wastewaters. However, initiating and restoring damaged PN performance is crucial for optimizing nitrogen removal efficiency without the use of chemical additives. In this study, a simultaneous partial nitrification and denitrification coupled with anammox (SPNAD) sequencing batch biofilm reactor was constructed to treat anaerobic digestion after sludge thermal hydrolysis pretreatment (STHP-AD) filtrate. The PN performance was successfully recovered through optimizing the operation mode of anoxic/oxic alternation within 120 days. Result showed that Nitrosomonas increased from 0.68 % to 3.43 %, while Nitrospira decreased to 0.06 %. The PN recovery also promoted anammox, with the only anammox bacterium of Candidatus Brocadia , detected in the mixing and biofilm sludge of 1.73 % and 1.41 %, respectively. The autotrophic denitrifying bacteria Thermomonas (increasing from 0.47 % to 23.85 %) and Truepera (rising from 2.31 % to 6.54 %) rapidly accumulated. After adjusting to the anoxic/oxic alternation ratio, the hydraulic retention time was shortened from 50 h to 37.5 h, and the oxic time was reduced to half of the initial operation. The PN recovery and anammox enrichment resulted in improving nitrogen removal approximately 20 %. Eventually, the SPNAD system realizes stable and efficient nitrogen removal with the influent nitrogen loading rate of 0.43 kgN/(m3·d), the ammonium removal efficiency of 94.73 ± 3.27 %, and the nitrogen removal efficiency of 72.98 ± 1.27 %. In this study, a new strategy using intermittent aeration while appropriately extending the oxic time was proposed to restore the system's ability to treat STHP-AD filtrate after PN disruption. [ABSTRACT FROM AUTHOR]

[Display omitted] • Photosynthetic O 2 -supported algal-bacterial AGS was achieved with gas circulation. • Gas circulation promoted biological utilization of GHGs including CO 2 , N 2 O and CH 4. • Enriched algae in biomass lowered CO 2 emissions but elevated N 2 O emissions. • The increased presence of algae in granules may deteriorate granular structure. Photosynthetic O 2 -supported algal-bacterial aerobic granular sludge (AGS) presents great potential in carbon emission mitigation and operation cost saving in wastewater treatment processes. This study used gas circulation to enclose the photosynthetic O 2 and the emitted CO 2 for the development of photosynthetic O 2 -supported algal-bacterial AGS in a pseudo-closed sequencing batch reactors (SBR), targeting greenhouse gas emission mitigation (including CO 2 , N 2 O and CH 4). Results showed that photosynthetic O 2 -supported AGS with abundant Cyanobacteria were achieved in this pseudo-closed SBR under strong light conditions. Although gas circulation enclosed acidic CO 2 , excessive Chlorophyll- a (Chl- a) in biomass still led to the increase of pH, followed by the occurrence of CO 2 limitation and the loss of functional strains and extracellular polymeric substances, eventually collapsing granular structure. Interestingly, gas circulation can reduce GHG emissions due to prolonged contact time between gases and microorganisms. Chl- a contents showed an inversely proportional relationship with CO 2 emission factors (0.04–0.61 kg-CO 2 /kg-COD), but over-high algae in biomass may induce more N 2 O emissions (0.45 % to 5.3 %) by affecting nitrification and denitrification processes. Compared to CO 2 and N 2 O, the emission of CH 4 was negligible. It was estimated that zero non-CO 2 GHG emissions could be achieved when stable granules containing Chl- a content of > 5.8 mg/g-MLVSS. This study proposed that achieving low-carbon photosynthetic O 2 -supported algal-bacterial AGS requires minimizing the adverse impact of existing algae on denitrification and nitrification. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrogen and high-value compounds production from glycerol and sodium metaborate. • Alternating feed of reagent in in consecutive steps in batch reactor at 300 °C. • Gas stream of 38–60% hydrogen, biogenic CO 2 (31–54%) and CO (4–13%) and CH 4 traces. • Aliphatic hydrocarbon resin with oxygenated carbon and aromatic cluster production. • C5-C6 cyclo -oxygenate selectivity varies between 40–60% based on biobased feedstock. In the global fight against climate change, the bio-based supply chain represents an interesting solution as it offers the potential to produce high-value-added products and bioenergy through the utilization of waste and by-products. In this work, a new route is proposed for the conversion of bio-based glycerol to H 2 /CO 2 and high value-added liquid and solid products. The innovative process used pure or crude glycerol or ethanol-glycerol mixture along with water and sodium metaborate as reagents at 300 °C under discontinuous conditions. The gas stream consists mainly of hydrogen, followed by biogenic CO 2 (31–54 %), CO (4–13 %) and CH 4 in traces. The presence of water in the tested crude glycerol improved the hydrogen selectivity to 55 %. Characterization of the liquid reaction products revealed the synthesis of products such as 1,2-propanediol, propanoic acid, acetic acid, cyclopentenones and cyclic diglycerol. In the solid phase, an aliphatic hydrocarbon resin with oxygenated carbon along the saturated chain and an aromatic cluster were also characterized by NMR, FTIR and TG analyses. Based on these findings, the global reaction route to the general reaction products was proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • The gas–liquid–solid mass transport/surface chemistry in a magnetically-stirred batch reactor. • DFT determined adsorption selectivity. • Established molecular structure–activity relationships. • Structure analysis based on STEM-EDS data. Catalyst surfaces enable the catalytic reactions via binding of substrates and lowering the reaction barriers to obtain the desired products. Separating the binding process from the reaction barriers enables us the understanding of surface properties and enables the reaction engineering strategies such as choice of solvents or functional groups protections. Through the modelling of the hydrodeoxygenation (HDO) of fatty acids, namely Stearic, Oleic, Linoleic, Myristic and Decanoic acid we show why the alkanes are the ideal solvent choice for NiMoS catalyst, why the alcohols side products form, regardless of the kinetic constant indicating fast dehydration, why the aldehydes intermediates are rarely detected and why hydrogenation of double bonds supersedes other kinetics events. We confirm the DFT calculations by integrating them into the kinetic model which confirms that the obtained results are sensible and usable in reaction engineering. The results are supported by the detailed characterization of the NiMoS catalyst. [ABSTRACT FROM AUTHOR]

• A criterion is proposed to estimate the heat transfer surface in batch reactors. • The proposed criterion allows for a more reproducible quality of the final product. • The proposed approach is kinetic-free. • The proposed criterion has been validated through some industrial data. A number of newly developed exothermic reactions of the fine-chemical industry can be safely tested at the industrial scale in an existing batch reactor since they cannot lead to dangerous reactor overpressures even under adiabatic conditions. However, when the process is scaled from a laboratory to an industrial reactor, the normal decrease of the heat transfer efficiency per unit volume can be so relevant that at the industrial scale the process cannot be thermally controlled, leading to a lower and less reproducible quality of the final product. In these cases, the industrial reactor must be equipped with an external heat transfer surface in addition to that provided by the reactor jacket only. The sizing of such an additional surface through conventional tools requires the knowledge of the heat release rate in the recommended temperature range and hence of the system kinetic behavior, which is often a missing information in the fine-chemical industry due to the fragmentation of the involved processes. In this work, a kinetic-free sizing criterion is presented for the temperature-controlled scale-up of intrinsically safe exothermic reactions carried out in the batch mode of operation, allowing for a simple and general estimation of the required heat transfer surface at the industrial scale from the analysis of the pseudo-adiabatic temperature trends measured during the original industrial batches. The proposed methodology has been validated using a set of process information about the final nitration step for the synthesis of an API as well as industrial-scale data collected during the scale-up of a water-in-oil emulsion polymerization for the synthesis of a polycationic thickener used in the cosmetic industry. [ABSTRACT FROM AUTHOR]

• Perovskite C a M n O 3 - δ was synthesized from natural ores through a simple process. • CaMnO 3 phase absorbs more Fe, Al, and Si present in the Mn ore compared to CaMn 2 O 4. • CLOU and reactivity of C a M n O 3 - δ were tested in both batch and CLC reactor system. • Low attrition was found after 29 h operation with CH 4 in the CLC reactor system. The potential for low cost of CO 2 capture using chemical-looping combustion (CLC) should not be compromised by costs associated with the oxygen carrier. This justifies studies of oxygen carrier materials with reasonable production costs. In this study, a perovskite calcium manganite (C a M n O 3 - δ), was synthesized from manganese ore and limestone through a straightforward process involving mixing with polyvinyl-alcohol, sintering, crushing and sieving. The calcium manganite produced exhibited two primary crystalline phases: CaMnO 3 (perovskite) and CaMn 2 O 4 (marokite). Experiments were conducted using both a batch fluidized-bed reactor and a 300 W CLC reactor system in continuous operation to assess the oxygen uncoupling and reactivity of the calcium manganite. The results show that the oxygen uncoupling ability increases with temperature. Full syngas conversion was achieved at relatively low temperatures and low fuel-reactor bed mass over fuel power ratio in the 300 W unit. Elevated temperatures and ratio of fuel-reactor bed mass over fuel power enhance methane conversion significantly. The attrition of the calcium manganite was low, around 0.1 wt%/h for the last 15 h operation with methane. Batch reactor tests of fresh and used materials showed that there was no reduction in reactivity after 29 h of fuel operation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Competition for electrons suppresses N 2 O reduction rates regardless of EA supply. • Co-enrichment with NO 3 – and N 2 O favours NOS activity under conditions of electron competition. • Co-enrichment with NO 3 – and N 2 O increases nosZ I type N 2 O-reducers. • Flavobacterium may favour N 2 O reduction on conditions of electron competition. The reduction rate of nitrous oxide (N 2 O) is affected by the electron competition among the four denitrifying steps, limiting the mitigation of N 2 O emissions during wastewater treatment. We foresee essential to understand how combinations of electron acceptors (EAs) affect the microbial composition and reduction mechanisms of denitrifying communities. We enriched three denitrifying communities from activated sludge biomass with equivalent loads of different EAs: NO 3 – (R1), N 2 O (R2), and NO 3 – + N 2 O (R3). The resulting enrichments were compared in terms of (1) reduction of nitrogen oxides in absence/presence of other EAs (NO 3 –, NO 2 –, N 2 O), (2) their denitrification gene composition and (3) their microbial community composition. Batch results showed the presence of NO 3 – and NO 2 – suppressed N 2 O reduction rates in all three reactors. The effect was lower in the mixed-substrate feed community than in the single-substrate feed under infinite sludge retention time and chemostat operation modes. N 2 O-reducers of type nosZ II were enriched when N 2 O serves as the sole EA, whereas nosZ I type N 2 O-reducers were more prone to enrichment with NO 3 – as EA. The EA composition rather than the sludge retention mode differentiated the microbial communities. The genus Flavobacterium seems to play a significant role in alleviating the suppression of the N 2 O reduction rate caused by electron competition. Limited conditions of electron supply are the norm independently of high C/N levels, and a community co-enriched with NO 3 – and N 2 O alleviates more the competition for electrons in the nitrous oxide reductase enzyme than communities enriched with NO 3 – or N 2 O individually. [ABSTRACT FROM AUTHOR]

• A self-regenerable oxygen system for biological removal of ammonium is reported. • NH 4 + removal efficiency strongly depends on microalgal photosynthesis and gas transfer. • Nitrogen concentration up to 82.5 mg/L favors nitrification by microalgae-bacterial consortia. • Combined mechanistic and empirical modeling revealed clear insight into N dynamics and DO profile. This study investigated self-regenerable oxygen system using microalagae-bacterial consortium for ammonium removal from wastewater and its kinetic modeling based on a combined mechanistic and empirical approach. By mechanistic modeling using a simple microalgal-bacterial Monod model, based on algal growth due to NH 4 +, NO 3 − and NO 2 −, the nitrogen and DO profiles were accurately predicted under different nitrogen conditions (low, medium, and high NH 4 + concentrations). The mathematical modeling results showed that sufficient oxygen was available for nitrification at low initial NH 4 + ammonium concentration levels, even when dual nitrogen substrate (NH 4 +–NO 2 −, NH 4 +–NO 3 − or NO 2 −–NO 3 −) or all three in combination (NH 4 +–NO 2 −–NO 3 −) were used, compared with high initial ammonium concentration levels. The DO profile was successfully used to monitor N transformation and N uptake in the PSBR based on net O 2 uptake rate, O 2 production rate, and O 2 saturation profile. By empirical modeling of the data obtained, the actual O 2 produced by microalgae with the different N species was calculated based on N mass balance and empirical equations. The empirical model further revealed that low NH 4 + concentration levels (up to 82.5 mg N/L) favored successful nitrification due to the sufficient production of O 2 in the system. However, NH 4 + concentration in the range 82.5–132.5 mg N/L affected the nitrification efficiency due to insufficient O 2 produced in the system, whereas high ammonium concentration results in nitritation/partial nitrification due to the high demand of O 2 by AOB and inhibition in the growth of NOB. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ultrasonication boosted hydrogen yield by 13% and purity by 7%. • Ultrasonication directed an extra 4.7% of carbon through the glycolysis pathway. • Ultrasonication shifted pathways and minimised electron carrier wastage. Biohydrogen is pivotal for hydrogen economy, providing a renewable, carbon–neutral source of hydrogen from organic waste and biomass. It addresses environmental concerns and supports circular economy principles. However, challenges like managing metabolic pathways and dissolved hydrogen hinder attainment of higher hydrogen yields. This study explored the impact of organic loading rates (OLR) and ultrasonication on glucose fermentation by Clostridium pasteurianum for biohydrogen production. Results showed ultrasonication, particularly at 10 g/L.d OLR, increased hydrogen yield from 1.04 to 1.28 mol-H₂/mol-glucose. Higher OLR boosted biogas production, and at 10 g/L.d OLR, ultrasonication improved hydrogen purity from 46% to 53%, enhancing yield by 13%. C. pasteurianum shifted metabolic pathways under higher OLR, increasing lactate production to address redox imbalance. However, ultrasonication negatively affected lactate and acetate reutilisation, redirecting carbon flux from lactate to butyrate, increasing hydrogen yield. Combining ultrasonication and increased OLR enhanced glycolysis carbon flux by 14.5% and reduced biomass carbon flux by 10.5%. Hydrogen yield, influenced by glycolysis carbon flux, reached 82% under ultrasonication and increased OLR. Ultrasonication mitigated inhibitory effects on electron carrier molecule re-oxidation, emphasising the need to balance biomass, dissolved hydrogen concentration, and OLR for optimal hydrogen recovery. Despite decreased acetate/butyrate ratio and unchanged theoretical hydrogen production with ultrasonication, hydrogen yield increased. This likely resulted from reduced electron carrier molecule wastage with biomass, influenced by higher biomass concentration and ultrasonication. The study underscored preventing electron carrier molecule washout for higher hydrogen production and recommends using batch reactors over continuous stirred tank reactors in dark fermentation operations. [ABSTRACT FROM AUTHOR]

• Kinetic rate constants for both steps of diphenhydramine synthesis are calculated. • Kinetics are developed by in-situ Raman and in-line low-field NMR spectroscopies. • Quantitative models are developed on a low-field NMR spectrometer. • The Arrhenius and Eyring parameters are calculated for the etherification step. • A discussion of the mechanistic implications of the solvent properties. Diphenhydramine is a first-generation antihistamine that is available over-the-counter to treat maladies such as allergic reactions and insomnia. Despite its ubiquity in society and high demand, the kinetics for either step of diphenhydramine synthesis have not been explored in detail. In this work, for the first step, a methodology has been devised to obtain kinetics from the heterogeneous halogenation of benzhydrol with hydrochloric acid in a batch reactor equipped with in-situ Raman probe and further verified with ex-situ low-field NMR spectroscopy. For the second step, the kinetics of etherification have been explored using a microfluidic flow reactor and at-line NMR spectroscopy in a variety of solvents. Arrhenius and Eyring parameters are determined for Step 2. We find that the reaction performance is well correlated with the acceptor number of the solvent indicating that the Lewis acidity of the solvent plays a significant role in the overall performance. [ABSTRACT FROM AUTHOR]

• An annular rotating flow loop reactor(ARLR) is developed to synthesize calcium hydrogen phosphate dihydrate(DCPD) crystals. • The unique internal loop and annular rotating flow field of ARLR delivered exceptional plug-flow characteristics. • The crystal morphology and particle size can be regulated precisely. • The product crystals can reach a length of 120 μm and a D 50 size of 70 μm. • ARLR marked a significant advancement in processing high-solid-holdup slurries. The synthesis of calcium hydrogen phosphate dihydrate (DCPD) involves a gas–liquid-solid three-phase slurry system that poses challenges for precise control using traditional batch reactors to produce crystals with controlled morphologies and particle sizes. In this study, an annular rotating flow loop reactor (ARLR) was developed to continuously synthesize DCPD. The unique internal loop and annular rotating flow field of the reactor delivered exceptional plug-flow characteristics, ensuring that the obtained DCPD exhibited a controlled morphology and particle size. The morphology of DCPD was adjusted to be bowknot-shaped (BS) agglomerate crystals, reaching a length of 120 μm and a D 50 size of 70 μm. The ARLR can achieve long-term stable operation with high-solid holdup slurries, outputting up to 125 g/h by maintaining precise and controllable flow and mixing conditions. Notably, ARLR marked a significant advancement in processing high-solid-holdup slurries, offering the adaptability to adjust the geometric design for various slurry systems and forecasting promising prospects. [ABSTRACT FROM AUTHOR]

[Display omitted] • The co-exposure of SUC and TCS had an antagonistic effect on nitrification system. • TCS and DAC (5 + 5 mg/L) aggravated the damage of ammonia oxidation performance. • The removal efficiency of SUC, TCS and DAC was about 4%, 90% and 45%, respectively. • SUC and TCS stress enriched si-RGs, but SUC, TCS and DAC stress enriched w-RGs. • The combined exposure of TCS and DAC aggravated the conversion of si-RGs to se-RGs. Sucralose (SUC) is an artificial sweetener for everyday consumption and often co-exists with disinfectants such as triclosan (TCS) and dialkyldimethyl ammonium compound (DAC) in sewage. Considering their continuous accumulation in sewage, it is essential to understand the impacts of their single and combined stress on the evolution of resistance genes (RGs) and microorganisms. In this study, three sequencing batch reactors (SBRs) were established, which were added with SUC, disinfectant, SUC and disinfectant, respectively, and named SSBR, DSBR and SDSBR in turn. There were four stages in total, the first two stages and the latter two stages were set to explore the effects of co-exposure of SUC and single disinfectant (TCS), SUC and combined disinfectants (TCS and DAC) on nitrification system, respectively. SSBR showed excellent ammonia oxidation performance in the whole operation stages. Compared with DSBR, the microorganisms in SDSBR under the combined stress of SUC and TCS were less inhibited. TCS and DAC destroyed the ammonia oxidation performance of DSBR and SDSBR. Within 120 days, the removal efficiency of TCS reached 90 %. In SSBR, 1 mg/L SUC promoted the proliferation of RGs, especially induced free RGs in water (w-RGs) to maintain high abundance and persistence. Compared with single stress, the abundances of intracellular RGs in sludge were higher under the combined stress of SUC and TCS, and the risk of RGs transmission was greater. The combined stress of SUC and disinfectants (TCS and DAC) led to a higher enrichment of w-RGs, exacerbating the risk of w-RGs transmission. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biological nitrate removal with municipal wastewater as co-substrate was demonstrated by CANDAN process; • High-efficient nitrogen removal with NRE and NRR of above 84 % and 0.6 Kg N/m3/d achieved; • Efficient denitratation with NTR above 84.6% always obtained despite increased municipal wastewater; • Increased municipal wastewater did not pose an adversely effect on anammox process; • Stable CANDAN process with dominated anammox sustained in treating nitrate sewage with varying concentrations. The innovative Complete Ammonium and Nitrate removal via Denitratation-Anammox over Nitrite (CANDAN) process represents a promising low-carbon technology for wastewater treatment, has been widely studied in sequential batch reactors (SBRs) treating synthetic wastewaters. This work focuses on the development of the CANDAN process within a continuous-flow Upflow Anaerobic Sludge Blanket (UASB) reactor for nitrate sewage treatment (NO 3 –-N: 100–1000 mg N/L), featuring varying proportions of real municipal wastewater as a co-substrate (61.3 mg NH 4 +-N/L, 191.5 mg COD/L). The results demonstrate consistently high N removal performance, with over 84.0 % of total nitrogen (TN) removed from the mixed wastewaters at a rate of approximately 0.6 Kg N/m3/d. As the proportion of municipal wastewater in the feed increased, the activity of denitrifying microorganisms improved. However, their growth was constrained by exacerbated endogenous respiration resulting from prolonged Hydraulic Retention Time (HRT) under a constant loading rate. The ideal nitrite production with the nitrate-to-nitrite transformation ratio (NTR) of above 84.6 % was always obtained. This sustained the dominance of the anammox pathway at around 80 % throughout the operation, underscoring its pivotal role in supporting the exceptional performance of the CANDAN process within the UASB reactor. Microbial analysis revealed an increase in species richness and diversity with higher proportions of municipal wastewater, while anammox functional bacteria exhibited slight enrichment in the later stages, further emphasizing the sustainability of the CANDAN process even with increased proportions of municipal wastewater. The outcomes of this study provide valuable insights into the successful development of a continuous-flow CANDAN process for highly efficient nitrate sewage treatment by incorporating real municipal wastewater as a co-substrate, advancing the goal of achieving carbon–neutral wastewater treatment practices. [ABSTRACT FROM AUTHOR]

[Display omitted] • Machine learning analysis identifies catalyst's key role in Me 2 SiCl 2 selectivity. • MeSiCl 2 -SiCl 2 Me and MeSiCl 2 -SiClMe 2 are main compositions of industrial HBRs. • MeSiCl 2 -SiClMe 2 prefers to produce MeSiCl 3 and Me 2 SiHCl based upon DFT insights. • Challenges & suggestions for upgrading HBRs to Me 2 SiHCl has been analyzed. Recently, the growing capacity of silicone monomers directly lead to a large accumulation of associated high-boiling residues (HBRs), which has become an urgent issue for limiting the sustainably development in industry. Dimethyldichlorosilane (M2) is an essential intermediate in silicone industry, which have been extensively applied in kinds of fields like architecture, electronics, new energy, medicine, transportation and plastic rubber. Consequently, the catalytic cracking of HBRs to produce value-added M2 is considered a promising strategy. However, most cracking catalysts exhibit low M2 selectivity in batch reactors. In this perspective, we initially provide an overview of the HBRs current cracking system. Moreover, the influence factors of M2 selectivity during HBRs-catalytic cracking system through machine learning (ML) methods are systematically calculated and analyzed. The latest findings regarding the actual components of HBRs feeding and their effluxes of HBRs-tri-n-butylamine cracking system are presented, as well as their distribution of final products. Finally, the existing challenges and suggestions for HBRs to M2, are given with the aim of providing novel research ideas and stimulating inspiration to drive toward a sustainable development for minimizing pollution and enhancing cost-effectiveness. [ABSTRACT FROM AUTHOR]

[Display omitted] • The combination of EAOPs and a biological treatment was studied. • This study was performed using batch and continuous EAOPs pre-treatment. • The presence of HCT and aromatic intermediates inhibit the µ-org activity. • The conditions allowing an efficient combined treatment were identified. • The combined process reached a quasi-complete mineralization yield of 91%. Improving the mineralization of concentrated pharmaceutical effluents by combining an electrochemical advanced oxidation process (EAOP) pre-treatment with a biological process is gaining interest. In this context, the objective of this study was to better understand how the conditions applied in the EAOP (anodic oxidation and electro-Fenton) pre-treatment influence the biological process in order to optimize the synergism. EAOP pre-treatment was applied in batch condition at lab-scale and in continuous mode in a bench-scale prototype. The presence in the solution of the pharmaceutic hydrochlorothiazide (HCT) at 10 to 100 ppm level and aromatic intermediates formed by its oxidation inhibited the activity of microorganisms. To perform an efficient combined treatment, it was evidenced that some specific operating conditions for the EAOP pre-treatment should be applied with the aim of (i) degrading the pollutant HCT while reaching a low mineralization degree, (ii) reducing the concentration of aromatic intermediates and (iii) promoting the formation of biodegradable compounds like carboxylic acids. The combined treatment was then applied using these optimal conditions. In the lab-scale batch reactor using a BDD anode, the mineralization yield reached 66 % including 38 % by the biotreatment whereas using Pt anode, the mineralization yield reached 85 % including 50 % by the biotreatment. The same strategy was then applied to the continuous prototype EAOP reactor with BDD anode and a mineralization yield of 91 % was reached including 31 % by the biotreatment. [ABSTRACT FROM AUTHOR]

• Silver nanoshells are synthesized using a central collision-type microreactor. • A large excess amount of ammonia is required to cover core particles with silver. • Formaldehyde with a weaker reducing power is a more suitable reducing agent than l -ascorbic acid. • PVP molecules not only increase the suspension stability but also promote the shell growth. • The intensive mixing of the microreactor is critical in the complete nanoshell formation. Silver nanoshells have wide-ranging applications spanning from catalysis to bio-sensing because of their unique optical and chemical properties. They are synthesized through a seed-mediated growth process, in which surfaces of the core particle are decorated with metal seeds followed by the growth of silver. However, a typical synthesis is a time-consuming batch-process which creates inhomogeneity in the shell structures. Hence, it is required to establish a quick, simple, and robust synthetic method. Using a central collision type microreactor instead of a batch reactor is advantageous because of its large surface to volume ratio and rapid mixing. In this study, we synthesize silver nanoshells by using such a microreactor and investigate the effects of the molar ratio of ammonia to silver ion, the types of reducing agents, and the addition of polyvinylpyrrolidone (PVP) on the complete nanoshell formation. Our experiments demonstrate that a large molar ratio of ammonia to silver ion is required to form silver-ammonia complexes and regulate the reducing power of reductants to cover the core particles with silver. Formaldehyde, due to its weaker reducing power, is found to be a more suitable reducing agent than ascorbic acid. PVP molecules serve not only as a stabilizer but also as a facilitator to help smooth shell growth. Most importantly, the use of the microreactor is critical to the formation of complete silver nanoshells. [ABSTRACT FROM AUTHOR]

• Carbon fibers (CFs) addition accelerated the maturation of aerobic granular sludge (AGS). • CFs inhabited the growth of filamentous bacteria. • Protein and polysaccharide were inclined to distribute in tightly bound EPS stimulated by CFs. • CFs and β-polysaccharides together provided skeletons for the stable core inside AGS. A novel granulation technique by adding carbon fibers (CFs) as the skeletons of aerobic granular sludge (AGS) was developed in this study. Three sequential batch reactors (SBRs) named R1, R2 and R3 were operated over 5 months under low hydraulic shear force (HSF). Comparatively, the R2 and R3 had short CFs and long CFs added to the sludge mixture, respectively. The results indicated that adding CFs accelerated the maturation of granules and improved the stability of AGS, while the AGS in R1 disintegrated twice due to the overgrowth of filamentous bacteria, and appeared in a mixture of flocs and AGS eventually. Total amount of protein and polysaccharide in extracellular polymeric substances (EPS) showed little difference among three reactors, whereas their contents in tightly bound EPS of AGS in R2 and R3 were much higher than that in loose bound EPS during granulation. Confocal laser scanning microscopy (CLSM) images showed that the β- d -glucopyranose polysaccharides of AGS in R2 and R3 were more concentrated in the outer layer, but uniformly distributed in the AGS in R1, indicating that CFs might maintain the structural stability of AGS by providing skeletons together with β- d -glucopyranose polysaccharides. High throughput sequencing analysis showed that the relative abundance of functional bacteria, especially Candidatus_Accumulibacter , was extremely increased due to the addition of CFs. This study indicated that adding CFs is an effective method for aerobic sludge granulation under low HSF. [ABSTRACT FROM AUTHOR]

• N-O containing compounds (NOCs) are an important group of pollutants. • Surface and soluble Fe(II) complexes had similar reduction mechanisms. • Linear correlation existed between the reactivity of surface vs soluble Fe(II). • Surface complexation facilitated the reduction of NOCs by Fe(II)-goethite. Both Fe(II) adsorbed onto mineral surfaces and soluble Fe(II) complexes are important natural reductants; however, no research has directly compared their reaction kinetics and mechanisms. In this work, the reduction kinetics of heterogeneous Fe(II)-goethite versus homogeneous Fe(II)-tiron were compared for the first time toward thirteen structurally diverse nitrogen-oxygen containing compounds (NOCs). The reduction of NOCs followed pseudo-first-order reaction kinetics in Fe(II)-goethite, with the rate constant k varying over a wide range from 8.56 h−1 to <0.0001 h−1. In electrochemical experiments where NOCs were physically separated from Fe(II)-goethite, k of carbadox was 3.6 times greater than that of a structurally similar compound that cannot complex with surface Fe(II), while such difference in batch reactors was 531 times. Similar differences in the reactivity of NOCs between the two reactors were reported for Fe(II)-tiron. The good linear cross correlations between the reactivity of Fe(II)-goethite and that of Fe(II)-tiron toward NOCs, nitroaromatics, and polyhalogenated compounds (R2 = 0.76–0.94) can be used to predict the reactivity of other structurally related compounds by both reductants. On the basis of the FTIR and UV spectra, surface complexation was further inferred; both the amino functional groups and the pyridine ring were involved in the complexation, with the ring-N more strongly involved than the ring-O. As opposed to the large differences observed in the reactivity of the two Fe(II) reductants, similar reactivity was obtained when an outer-sphere reductant dithionite was employed. Overall, these results show that complexation between certain NOCs and surface-associated Fe(II) existed which facilitated the reduction reaction. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Continuous flow processes allow scaling-up of LDH production with constant quality. • Morphology and size of particles are controlled. • Evolution of the reactor design from tank to microfluidic technology is evidenced. • Heat and mass transfers are improved, and residence times are reduced. • Nanosheets, LDH-based hybrids and nanocomposites are obtained. Abstract Continuous production processes allow scaling up of layered double hydroxides (LDHs) and avoid the drawbacks induced by conventional coprecipitation. These drawbacks result from variable supersaturation rate due to non constant pH and concentration of the solutions and from long residence times hindering a fine control of the size and morphology of the particles. Continuous flow processes allow reducing the residence time and maintaining almost constant supersaturation producing LDHs in large amounts with constant quality. We report here the different continuous flow methods for the production of LDHs particles with controlled size and morphology or individual nanosheets, and of LDH-based hybrids and nanocomposites. The paper will focus on the design of the reactors showing a decrease of their volume and an improvement of the mixing and heat and mass transfers. Cylindrical tank under steady-state conditions lead to particles with a narrower size distribution than in batch reactor. Then processes with vigorously stirred microreactors in the so-called in-line dispersion-precipitation method were developed. Counter-current flow reactors with particles formed at the interface of solutions flowing up and down were further used to obtain ultra-fine LDH nanoplates and efficient surface modification with surfactants. Hydrothermal continuous or co-flow reactors exhibit great versatility allowing the preparation of exfoliated or functional LDHs, LDH nanoplates on alumina-coated substrates, and reduced graphene oxide/LDH nanocomposite films. The microfluidic technology is very promising for preparing LDHs of different compositions and functionalities. The reaction conditions as well as the structural and morphological properties of the materials are discussed and applications are reported. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A biological-chemical treatment of a complex industrial wastewater has been studied. • Real Hazardous wastewater consisted of a mixture of special chemical effluents. • Acclimation of the aerobic culture used was successfully investigated. • Solar photocatalytic ozonation was able to remove biorecalcitrant compounds. Abstract The feasibility of the treatment of a complex industrial wastewater by aerobic biodegradation in a sequential batch reactor (SBR) followed by ozone-based advanced oxidation processes (AOPs) has been studied. The industrial wastewater had high organic load (TOC > 3 g L−1, COD > 12 g L−1, BOD 5 > 2 g L−1) including some toxic/harmful compounds and high concentration of metal and other inorganic species. SBR treatment of the industrial wastewater diluted with urban wastewater (dilution 1:5), was successful after complete acclimation of the mixed culture (i.e., >50% COD and TOC removals). Nevertheless, the SBR effluent was still not acceptable to be disposed into the environment (c.a. COD 850 mg L−1) so ozonation, solar photo-ozonation and solar photocatalytic ozonation processes were investigated as further polishing treatments. Thus, the sequential combination of aerobic biodegradation and solar photocatalytic ozonation with a TiO 2 -based catalyst led to an effluent suitable for discharge into the aquatic environment according to environmental regulations (COD < 125 mg L−1, BOD 5 < 25 mg L−1). [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Molar flow rates and, hence, conversion and selectivity values are obtained with a higher accuracy. • It is a one-step procedure, so iterative steps are not required in this simple and automated routine. • It is applicable in all fields of research where (molar) balances or concentrations are used. • The procedure is executed in Excel®, which is accessible by every user – no need for special license. • Parameter estimation, using treated data, results in smaller confidence intervals and lower RSSQ. Abstract In continuous flow reactor analyses, the experimentally obtained molar flow rates of unreacted reactants and formed products are called useful if the corresponding atom balances are closed, i.e., within 90–110%. This manuscript (1) shows that even for the validity condition of a balance between 95% and 105%, deviations for conversion and selectivity can be very pronounced and (2) offers, likewise, a very simple a posteriori calculation procedure to address these deviations. To validate the proposed procedure, called 'CLOBAL' – after ' clo sing the bal ances', an example from butane oxidative dehydrogenation (ODH) is taken and it is clearly shown that the CLOBAL method gives values for conversion and selectivity, closest to the 'real' values, compared to the conventional methods, i.e., without correction. As an example of batch reactor operation, the aldol condensation towards jasmine aldehyde is taken to show that the application of the presented CLOBAL procedure gives corrected concentrations values which result in more accurate kinetic parameter estimates with a lower residual sum of squares. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Novel Fe/Cu@Pd catalysts were developed for PNP reduction in aerobic conditions. • PNP reduction is via Fe/Cu@Pd efficiently catalyzing NaBH 4 as electron sources. • PNP reduction by this catalysis was 25-fold higher than that without NaBH 4. • The product of BH 4 − is non-toxic B(OH) 3 posing neglect influence on ecosystems. • A Fe/Cu@Pd based catalytic membrane reactor was finally assembled and evaluated. Abstract Nanoscale zero-valent iron (nZVI)-based technology has gained a great success in anaerobic groundwater remediation, while the high reactivity of nZVI towards oxygen and protons restricts extending its further application in wastewater treatment under atmospheric conditions. To address this challenge, a novel Fe/Cu@Pd ternary metallic catalyst was synthesized, and its catalytic efficiency with sodium borohydride (NaBH 4) for reducing 4-nitrophenol (PNP) under aerobic conditions was examined in batch and continuous-flow modes. In comparison to the reaction in anaerobic condition without adding NaBH 4 , the rate constants of reduction kinetics for PNP removal in aerobic conditions can be significantly enhanced up to 0.746 min−1 that is about 25-fold higher. Influence of different background ions on the performance of the catalyst was also systematically investigated, showing that humic acid and nitrate pose relatively strong interference on PNP reduction. The reduction mechanisms were also examined by means of spectroscopic and electrochemical approaches, and the results indicate that enhancement of reduction kinetics is likely due to the fact that catalytic reaction of BH 4 − by Fe/Cu@Pd nanoparticles can constantly provide electrons and active hydrogen species under aerobic conditions. Finally, a Fe/Cu@Pd based catalytic membrane reactor has been successfully assembled for PNP removal. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • PHA-storage capacity of a MMC does not decrease by ammonia oxidation occurrence. • Ammonia oxidation to nitrite is due to the free ammonia concentration or low HRT. • The PHA produced was composed by HB and HV in a ratio of 60:40. • Comamonas , Azoarcus and Thauera were the dominant PHA-accumulating bacteria. Abstract The nitrifying activity in mixed cultures enriched to accumulate polyhydroxyalkanoates (PHA) is in general inhibited by the addition of chemicals, such as allylthiourea (ATU). In the present study, a sequencing batch reactor was inoculated with a mixed microbial culture enriched in PHA-accumulating microorganisms, operating under complete aerobic conditions, feast/famine regime and with ATU addition. Genera Comamonas , Azoarcus and Thauera , all of them known as PHA-accumulating bacteria, were the dominant microbial populations present in the mixed culture. They showed a PHA storage capacity up to 60.0 wt%, as hydroxybutyrate (HB) and hydroxyvalerate (HV), in a HB:HV ratio of 63:37. After 20 days of operation, ATU addition was stopped and the reactor was run under the same operational conditions for 400 days. The development of partial nitritation activity (ammonia oxidation to nitrite) was observed, presumably due to free ammonia inhibition or the selected sludge retention time. Ammonium oxidizing bacteria (AOB) from genera Nitrosomonas , Nitrosococcus and Nitrosospira were detected, whereas the composition of the dominant PHA-accumulating microbial populations was the same as in the inoculum. This enriched mixed culture reached a maximum PHA accumulation of 59.2 wt%, with a HB:HV ratio of 59:41. Results showed the simultaneous occurrence of partial nitritation and the enrichment in PHA-accumulating microorganisms, which did not affect the maximum PHA storage capacity of the system. [ABSTRACT FROM AUTHOR]

• Details of development of continuous BT-based H 2 release system are presented. • Operational and design strategies of dehydrogenation system are obtained. • Strategies achieving a round-trip efficiency >70 % are proposed and assessed. • TEA reveals potential for 11.8% reduction in cost through enhanced efficiency. • Solutions for further advancing system efficiency are presented. We present a highly efficient method for hydrogen release from perhydro-benzyltoluene (H 12 -BT), one of the most promising liquid organic hydrogen carriers (LOHCs) in the current energy landscape. Despite the demand for scalability, dehydrogenation of H 12 -BT has so far only been subject to published studies on batch reactors at the laboratory scale. Here, we establish a continuous bench-scale 2.3 Nm3-H 2 /h-level (5 kg-H 2 /day) catalytic dehydrogenation system using H 12 -BT. Parametric analysis provides insights into operational and design strategies for large-scale H 12 -BT dehydrogenation systems. The proposed model for the system energy analysis enables outlining a path to elevate the round-trip efficiency (RTE). The basis of this is the incorporation of well-managed thermal systems and hydrogenation-based power generation, such as solid oxide fuel cells (SOFCs) and combined cycle gas turbines (CCGTs). These strategies, quantitatively assessed, demonstrate the feasibility above 70 %. Through techno-economic analyses (TEA), the dehydrogenation cost reduction associated with efficiency improvement is assessed, showing up to approximately 11.8 % cost reduction. This study propels efficient dehydrogenation system advancement, fostering a sustainable hydrogen supply within the global chain. [ABSTRACT FROM AUTHOR]

[Display omitted] • Continuous flow homogeneous nitration of 2,4-Difluoronitrobenzene was established. • The effect of mixing on the nitration reaction process was analyzed by dimensionless number. • Compared to batch reactors, microreactors greatly reduce nitration reaction time. • Kinetic model of the homogeneous nitration reaction was developed. In this study, we first experimentally demonstrated that the homogeneous nitration reaction process in capillary T-micromixers was greatly influenced by the limitations of mixing. Therefore, to improve the mixing effectiveness, we investigated the intensification of liquid mixing in the heart-shaped microreactor. Compared with the capillary T-micromixer, the mixing effectiveness in the heart-shaped microreactor was improved by three orders of magnitude, resulting in a conversion rate of 98.5 % and a reduction in residence time by two orders of magnitude compared to batch reactors. Furthermore, we have established a kinetic model that eliminates interphase mass transfer resistance and verified its accuracy by comparing the calculated values with the experimental ones. The mixing properties in the microreactor were revealed using the Damköhler number, Peclet number, and the mixer effectiveness. These findings contribute to the development of nitration reactions by highlighting the advantages of microreactors in this area and offer guidance for potential applications within the chemical industry. [ABSTRACT FROM AUTHOR]

[Display omitted] • The high-density 3D MFCs with optimized channels and volumes were designed using femtosecond laser technology. • The Barker's transformation ensured fast and efficient gas–liquid mass transfer. • Grignard reagents were produced at room temperature on demand and rapidly converted. • The conversion of CO 2 into value-added chemicals were completed within 40 s. • The space–time yield was much higher than batch reactors. Efficient conversion of low reactive CO 2 within a short residence time of flow chemistry presents a challenge. We have tackled this issue by developing 3D microfluidic chips (MFCs) with high-density, small-diameter, and large-volume for CO 2 gas–liquid reactions using femtosecond laser technology. Our innovative design effectively shortens reaction times while satisfying the required temperature and pressure conditions. One of the key features is the integration of the 3D Barker's transform structure, which provides an efficient gas–liquid contact area for mass and heat transfer, even at low Reynolds numbers. As a proof of concept, we synthesize 2,4,5-trifluorobenzoic acid and various other fluorinated carboxylic acids in 3D MFCs using Grignard reagents and CO 2. Impressively, the Grignard reagents can be generated in situ and utilized at room temperature, and the CO 2 carboxylation reaction with 3D MFCs takes only 40 s with a yield of 97 %. Our findings highlight the feasibility of this multifunctional, efficient, and fast CO 2 flow conversion process, providing a valuable tool to produce value-added chemicals via 3D MFCs techniques. [ABSTRACT FROM AUTHOR]

[Display omitted] • Continuous HMFOR to produce FDCA at the record rate of ∼ 2 kg/day was developed. • Reaction parameters were optimized to minimize HMF degradation and maximize purity. • FDCA was produced at high yield and purity, comparable to commercial product. • At least 48 h of continuous operation was demonstrated. Electrochemical oxidation of 5-hydroxymethylfurfural (HMFOR) stands out as an efficient and sustainable approach for 2,5-furandicarboxylic acid (FDCA) production. However, despite numerous catalyst advancements, the industrial adoption of this process faces significant challenges, stemming from limitations in scalability and high device costs. To address this gap, we developed a scalable HMFOR process for continuous FDCA production. Key parameters such as electrolyte concentration, anodic and cathodic catalysts, types of sparge gas, and current density were found to be critical to the yield and quality of the isolated FDCA products. NiFeOOH anode and Pt cathode operated at 33.3 mA cm−2 in 0.33 M KOH and O 2 environment were chosen as they provided the fastest oxidation kinetic and minimized HMF degradation rate, hence producing FDCA with high yield and purity. Using the optimal conditions identified in a milligram-scale batch reactor, we constructed a 2-liter CSTR with a novel electrode design accommodating 100 A of current. This process achieved an unprecedented FDCA production rate of ∼2 kg per day and space–time yields of up to 295 μmol h−1 cm−2, along with exceptional stability for 48 h. The isolated FDCA demonstrated comparable purity and color to commercial products. This simple and robust continuous reactor design can be applied to other electrochemical biomass valorization processes, potentially replacing conventional electrolyzers. [ABSTRACT FROM AUTHOR]

Highlights • Production of NaH from Na is a liquid-liquid-gas-solid system. • A new mathematical model was developed for the production of NaH. • The DAE system was solved numerically. • The model described very well the kinetic data from the slurry reactor. • The model can be used for process design. Abstract Sodium hydride is a powerful reduction agent used in chemical industry. Industrial production of sodium hydride through hydrogenation of melt sodium dispersed in mineral oil is very demanding because of the complex multiphase system (liquid-liquid-gas-solid) and safety aspects. A new mathematical model was developed for the production of solid sodium hydride from dispersed liquid-phase sodium and molecular hydrogen. New rate equations were derived for the hydrogenation process of dispersed sodium droplets in a semi-batch reactor. The model comprises surface reactions as well as liquid-solid mass transfer effects of hydrogen. The properties of the differential-algebraic model were investigated by numerical simulations and the model was verified with experimental data of sodium hydrogenation in an isothermal, intensively agitated semi-batch reactor. The kinetic and mass transfer parameters included in the model were estimated successfully with non-linear regression analysis and the model gave a good reproduction of the experimental data. The molecular-level model can be used for the design and optimisation of sodium hydride production processes. [ABSTRACT FROM AUTHOR]

This study aimed at assessing the performance and microbial community in a granular one-stage partial nitritation-anammox sequencing batch reactor (PNA-SBR) subjected to temperature transition from 25 to 15 °C without biomass acclimation. The PNA-SBR was operated by controlling the oxygen transfer rate (OTR) according to the ammonium loading rate (ALR), which resulted in micromolar (µM) bulk dissolved oxygen (DO) concentration. The applied strategy proved to be feasible to operate the one-stage PNA-SBR at mainstream conditions because it was possible to control nitritation according to anammox rate. Nitrogen removal rate (NRR) of 330.24 ± 25.36 mg N·L −1 ·d −1 was achieved at 25 °C. Nitratation control by µM bulk DO limited the NO 3 − production :NH 4 + removed at 0.28 ± 0.04. No instability was experienced by decreasing the temperature to 15 °C, but removal rates were adapted to the resulting anammox activity, which decreased at low temperature. After temperature transition, nitratation was kept controlled and the NO 3 − production :NH 4 + removed molar ratio remained at 0.33 ± 0.05, although anammox activity deteriorated and higher nitrate production was obtained. Sequencing analysis revealed the dominant bacterial groups in the microbial community that clustered within the phyla Planctomycetes , Proteobacteria , Chloroflexi , and Bacteroidetes . Temperature drop only affected bacterial abundance, but the main bacteria involved in nitrification and anammox processes did not change during the study. Candidatus Kuenenia was the main anammox genus. Moreover, the presence of bacterial groups associated with heterotrophic metabolism indicates denitrification might be supported by the release of dissolved organic carbon due to bacterial lysis, and lower nitrate effluent concentration could be reached in PNA reactors. [ABSTRACT FROM AUTHOR]

Ammonia and long chain fatty acids (LCFA) are two major inhibitors of the anaerobic digestion (AD) process. The individual inhibitory effect of each of these two inhibitors is well established; however, the combined co-inhibition effect has not been thoroughly assessed yet. In the current study, the ammonia-LCFA synergetic co-inhibition effect was investigated in both batch and continuous experiments. In the batch experiments, a clear ammonia-LCFA synergetic co-inhibitory effect was identified when the LCFA concentrations were higher than 0.05 g oleate L −1 and ammonia levels between 4.0 and 7.0 NH 4 + -N L −1 . This synergetic effect for LCFA and ammonia levels above 1.1 g oleate L −1 and 4.5 NH 4 + -N L −1 , respectively, was validated in continuous reactors experiments. Nevertheless, adaptation of the AD microbiome to this synergetic co-inhibition could occur after a period of continuous operation. A potential mechanism to explain the synergetic co-inhibition lies on the initial inhibition of methanogens caused by ammonia resulting in increased VFA and hydrogen concentrations, which in turn renders β-oxidation of LCFA thermodynamically unfavourable and thereby brings about further excess accumulation of LCFA and consequently higher unspecific toxicity of all AD steps. This is a vicious cycle, which makes the combined inhibition of the two toxicants more severe, compared to the sum of their individual inhibition effects at the same operational conditions. [ABSTRACT FROM AUTHOR]

Zerovalent iron (ZVI) is commonly used for water treatment under aerobic conditions such as sequestration of metals. Sulfide-modified ZVI (S-ZVI) is attracting increasing attention for its easy preparation and high reactivity with environmental pollutants. The processes responsible for contaminant removal can be a complex mixture of redox, sorption, and coprecipitation processes. In this paper, ZVI and S-ZVI were used to sequester antimonite (Sb(III)). The rates of Sb(III) sequestration were determined in open, well-mixed, batch reactors. The effects of various experimental variables were investigated, including pH, iron dose, initial concentrations of Sb(III), aging time of the ZVI and S-ZVI, addition of Fe 2+ , mixing rate, etc. The results showed that S-ZVI can significantly enhance the Sb(III) sequestration, and under basic conditions in this study, the k obs (0.018 min −1 ) obtained in the S-ZVI system was approximately 15 times higher than the 0.0012 min −1 obtained in the ZVI system. Solid phase characterizations were conducted to assess the influence of sulfidation on the morphology and surface geochemistry of ZVI. Scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDS) confirmed the presence of sulfur. X-ray photoelectron spectroscopy (XPS) indicated the oxidation of Sb(III) to Sb(V) and adsorption and coprecipitation onto the iron oxides is the mainly sequestration process. The FeS layer on ZVI is more conductive than oxides and therefore accelerates electron transfer. In addition sulfidation promotes the corrosion of iron and the formation of ferrous iron, which further enhances the ferric iron oxide formation, thereby favoring adsorption and oxidation of Sb(III). [ABSTRACT FROM AUTHOR]

In this study, the aggregation of nine pyridine-degrading strains was investigated for the acceleration of the aerobic granulation process, with emphasis on the coaggregation mechanisms involved. Rhizobium sp. NJUST18 and Shinella granuli NJUST29 (with strong aggregation ability but with relatively poor pyridine degradation ability) and Paracoccus versutus NJUST32 (with strong pyridine degradation ability but with poor aggregation ability) were chosen as inocula for aerobic granulation. The combination of NJUST18 + NJUST29 demonstrated more powerful coaggregation abilities and comparable pyridine-degrading ability compared with NJUST18 + NJUST32, NJUST29 + NJUST32 and the individual strains. The investigation of the coaggregation mechanism indicated that the combination of NJUST18 + NJUST29 presented the highest extracellular polymeric substances (EPS) content of 232.79 mg gVSS −1 and the second messenger cyclic diguanylate (c-di-GMP) content of 268.56 mg gVSS −1 , making the combination beneficial for aerobic granulation. In the sequential batch reactors (SBRs) inoculated with the combination of NJUST18 + NJUST29, aerobic granules with diameter of 0.2–0.5 mm was formed after operation period as short as 42 days, demonstrating that the combination of NJUST18 + NJUST29 as inocula in aerobic granulation system had promising potential for the treatment of high-strength pyridine wastewater. [ABSTRACT FROM AUTHOR]

Emissions of the greenhouse gas nitrous oxide from the Partial Nitritation-Anammox process are of concern and can determine the carbon footprint of the process. In order to reduce nitrous oxide emissions intermittent aeration regimes have been shown to be a promising mode of operation, possibly due to an effective control of accumulation of nitrogen intermediates. However, due to frequent changes of redox conditions under intermittent aeration regimes, nitrous oxide production and emissions are dynamic. In this study the production and emission dynamics of nitrous oxide in an intermittently aerated sequencing batch reactor were monitored in high temporal resolution, the contribution of different redox conditions to overall nitrous oxide production was quantified and the most relevant factors for nitrous oxide production were identified. The average fraction of nitrous oxide produced (per unit ammonium removed) was 1.1 ± 0.5%. Cycle-averaged approx. 80% of nitrous oxide was produced during aerated phases, the remaining 20% were produced during non-aerated phases. Yet, the intra-cycle dynamics of nitrous oxide were substantial. The net-production rate of nitrous oxide during aerated phases correlated with the ammonia removal rate, whereas the concentration of nitrite determined the production during non-aerated phases. While aerated phases contributed predominantly at the beginning of reactor cycles, non-aerated phases became the dominant source of nitrous oxide at the end. Particularly low net-production rates were observed at ammonia removal rates below 5 mg NH 3 -N*gVSS −1 *L −1 , when the fraction of nitrous oxide produced was 0.011 ± 0.004% (per ammonia removed). Based on the nitrous oxide dynamics and correlations, reactor operation at relatively low nitrogen loadings (below 100 mg NH 4 + -N*L −1 ), ammonia removal rates of approx. 5 mg NH 3 -N*gVSS −1 *L −1 and nitrite concentrations below 1 mg NO 2 −1 -N*L −1 appears as beneficial for low emission of nitrous oxide. [ABSTRACT FROM AUTHOR]

[Display omitted] • A catalytic membrane reactor using MoS 2 laminates for p -nitrophenol reduction. • Laminar membranes were fabricated by pressure-assisted filtration using MoS 2 nanosheets. • Laminar MoS 2 membrane demonstrated continuous reaction without deactivation. • MoS 2 membranes exhibited higher catalytic performance than metal-based membrane reactors. • An effective approach to constructing 2D nanochannel reaction spaces. MoS 2 nanosheets exhibit high specific surface areas and pronounced catalytic activity and so are an alternative to noble metal catalysts. However, the deactivation of these materials because of aggregation and loss during catalytic reactions is a concern. The present work proposes a catalytic membrane reactor concept based on two-dimensional nanochannels formed in MoS 2 laminates and demonstrates the continuous reduction of p -nitrophenol (p -NP). Laminar MoS 2 membranes were fabricated by pressure-assisted filtration using MoS 2 nanosheets prepared via Li intercalation. These membranes provided a flux of 26 L m−2h−1 with a p -NP conversion of approximately 90% at 0.5 bar. The flux and conversion could be controlled by varying the applied pressure. The present MoS 2 membranes showed stable flux and conversion values during a 5 h permeation test and demonstrated the continuous conversion of p -NP into p -aminophenol without any loss or aggregation of the MoS 2 nanosheets compared with a reaction in a batch reactor. Furthermore, surface functionalization of MoS 2 nanosheets using iodoacetic acid was found to improve the stability of the laminar structure during drying. These laminar MoS 2 membranes also exhibited higher catalytic performance than has been reported for metal-based membrane reactors. This study establishes an effective approach to constructing two-dimensional nanochannel reaction spaces using MoS 2 nanosheets. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cultivated GS dominated by DGAOs under the low phosphorus condition. • The enrichment of DGAOs in GS promoted the secretion of PS. • CaCO 3 formed inside the GS. • The formation of CaCO 3 was related to the metabolism of DGAOs. Denitrifying glycogen-accumulating organisms (DGAOs) are believed to be associated with sludge granulation in wastewater treatment plants (WWTPs). In this study, granular sludge (GS) dominated by DGAOs formed after 136 days of cultivation in a sequencing batch reactor under low phosphate influent conditions. The average phosphorus removal and denitrification efficiency in the stable operation stage were 84.9% and 54.3%, respectively. The percentages of DGAOs and denitrifying phosphate-accumulating organisms in GS were 17.1% and 0.5%, respectively. The main species of DGAOs in GS were Candidatus Competibacter and Candidatus Contendobacter. The excessive secretion of exopolysaccharide induced by the enrichment of DGAOs improved the viscosity of extracellular polymeric substances, thus promoting the initial sludge granulation and subsequent rapid enlargement of GS. The X-ray diffraction analysis revealed that the main composition of the inorganic crystal inside GS was CaCO 3. The metabolism of DGAOs caused a high pH environment, leading to the preferential formation of CaCO 3. This study reveals the important role of DGAOs in sludge granulation, which can help WWTPs formulate specific operation strategies to promote the extent of sludge granulation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Efficient nitrite production with high PD activity was achieved even at an influent nitrate of 800 mg N/L. • P removal initially increased with influent nitrate, but decreased with further increments beyond 400 mg N/L. • High Ca had minor effect on nitrite production, but facilitated P removal with maximum efficiency of 96.9% achieved. • PD-HAP granules tended to disintegrate at nitrate >400 mg N/L, while good settleability still obtained. • Controlling pH levels is expected to enable high-efficiency nitrite production and P removal from high-nitrate wastewater. This study introduces a novel PD-hydroxyapatite (HAP) coupled granular sludge process that efficiently produces nitrite while also addressing the issue of phosphorus (P) removal. Three laboratory-scale sequencing batch reactors (SBRs) were operated with varying calcium (Ca) concentrations, the performance of nitrite production, P removal, and the characteristics of PD-HAP granules under increasing nitrate concentrations (200–800 mg N/L) were investigated. Results demonstrated an increase in nitrite production with influent nitrate, with high PD activity maintained even in the presence of elevated nitrite levels. P removal improved as influent nitrate increased to 400 mg N/L but declined thereafter, likely due to the elevated pH promoting carbonate formation, which competed with phosphate for Ca2+. Supplying a higher Ca2+ concentration improved P removal, with R3 achieving a maximum removal efficiency of 96.9% at an influent nitrate of 400 mg N/L, surpassing R2 (85.7%) and R1 (70.0%). Additionally, it was observed that PD-HAP granules increased in size with higher nitrate concentrations but turned to be disintegrated with small granules formed when nitrate exceeded 400 mg N/L. However, despite this, the granules still maintained good settleability, with only a slight increase in sludge volume index (SVI 5) from 14.8 to 25.9 ml/g MLSS. This study demonstrated the tremendous potential of PD-HAP granular sludge process for treating high-nitrate wastewater in combination with anammox. [ABSTRACT FROM AUTHOR]

Most batch reactor methane thermal decomposition (MTD) studies have focused on sub-atmospheric pressures. In this study, MTD experiments were performed between 892 K and 1292 K and 4 atm inside a quasi-isothermal quartz batch reactor at residence times ranging from 0 to 300 s. At a given temperature, elevated pressure resulted in higher methane conversion compared with the sub-atmospheric conditions. A zero-dimensional, closed, isochoric, homogeneous gas-phase model was used to compare numerical predictions from available reaction mechanisms in literature to experimental data. It was found that most models accurately predict conversion at low pressure and high temperature and at high pressure and high temperature, but did not accurately predict methane, hydrogen, and intermediate species mole fractions at 4 atm and either 892 K or 1093 K. A reaction path analysis showed the reactions responsible for the delay in hydrogen formation at elevated pressure are 2CH 3 (+ M) ⟺ C 2 H 6 , C 2 H 6 ＋ CH 3 ⟺ C 2 H 5 ＋ CH 4 , C 2 H 6 ＋ H ⟺ C 2 H 5 ＋ H 2 and C 2 H 5 (+ M) ⟺ C 2 H 4 ＋ H, where M is the collision partner. A gas-phase model accounting for the solid carbon shows that the observed discrepancy is not due to the unavailability of the carbon formation model but to slower reaction kinetics, especially at lower temperatures. The experimental data presented can be used to obtain a methane pyrolysis reaction mechanism suitable for high pressure conditions. • High pressure batch reactor experimental data for methane thermal decomposition is obtained. • Reaction models underpredict pyrolytic conditions at 892 K and 1093 K and 4 atm. • Including solid carbon did not improve model predictions at 892 K and 1093 K. • Methane converting to methyl radical and hydrogen atom is the rate-limiting step. • The data presented can be used for training reaction mechanisms at high pressures. [ABSTRACT FROM AUTHOR]

Integration of black liquor gasification in a pulp mill without disturbing upstream processing by partial utilization of black liquor. [Display omitted] • The main monomeric compounds in the aqueous phase were phenol, guaiacol, and syringol. • Reducing the p H slightly improved the extraction of the phenol and guaiacol. • Lower p H hinders the ethyl acetate hydrolysis during liquid-liquid extraction. • The phenolic products have been degraded with increasing treatment temperature. The goal of this work was to study the effect of pH on the extraction yield of phenolic compounds from liquid phases recovered after the hydrothermal treatment of black liquor in the batch and continuous reactors at 280 and 350 °C. The p H values of the recovered liquid phases under investigation were adjusted to 9, 8, and 7. The liquid-liquid extraction was subsequently performed using ethyl acetate for 4 h at room temperature. The identification and quantification of phenolic products were conducted using GC-Mass analysis. The main monomeric compounds identified in the aqueous phase were phenol, guaiacol, and syringol. The results indicated that reducing the p H slightly improved the phenol and guaiacol extraction from the various recovered liquid phases after hydrothermal treatment. However, reducing the p H of liquid phases greatly increased the extraction yield of syringol. This was very noticeable in the recovered liquid phases after treatment at 280 °C, where the quantity of syringol was initially high. Additionally, a lower p H hindered the ethyl acetate hydrolysis during liquid-liquid extraction. The extraction experiments with various p H also confirmed the superior performance of the continuous reactor over the batch reactor to obtain the phenolic compounds. In addition, the phenolic products degraded as the treatment temperature increased from 280 to 350 °C. [ABSTRACT FROM AUTHOR]

[Display omitted] • Established a continuous flow microflow system for homogenous copolymerization of ethylene and vinyl acetate. • Proposed an efficient stop-flow method for kinetic study and reactivity ratio measurement. • Developed a simple kinetic equation for predicting total monomer conversion. • Precisely measured reactivity ratio of ethylene and vinyl acetate in dimethyl acetate. Ethylene content in ethylene–vinyl acetate copolymers (EVA) is a key factor that determines its further usage. While conventional batch reactor for EVA synthesis faces the problem of heterogeneous reaction environment and temperature control. A microflow system was designed to avoid these problems and facilitate the synthesis of EVA with controlled ethylene content. Continuous flow synthesis of EVA by solution free radical copolymerization was realized homogeneously based on this microflow system. 13C NMR spectra indicate that EVA obtained in microflow system has less ethylene concentrated sequence than EVA obtained in batch reactor. By operating the microflow system in a stop-flow method, we developed a simple kinetic model of copolymerization and measured the reactivity ratios of ethylene and vinyl acetate copolymerization in tert -butyl alcohol and dimethyl carbonate. The microflow system is demonstrated to be a powerful tool in kinetic and mechanism study and engineering application of copolymerization processes involving monomers which are gas phase under conventional condition. [ABSTRACT FROM AUTHOR]

• The mass loss rate in PE pyrolysis at 500 °C is much higher than previously reported. • Mass transfer and reaction interplay can be used to steer the product distribution. • Lower temperature and higher pressure lead to lower molecular weight products. An attempt to determine the the intrinsic kinetic of polyolefins pyrolysis is presented. For this, pyrolysis experiments of polyethylene were performed in a screen heater reactor, where the effects of mass and heat transfer on the pyrolysis process are minimized. First-order mass loss rate constants obtained at 500 °C were circa 0.5 and 1.3 s−1 for HDPE and LDPE, respectively, which are significantly higher than the majority of the values reported in the literature. At 450 °C, the mass loss rate of HDPE was lower, circa 10−2 s−1. Additionally, we have observed that the interplay between mass transfer and the depolymerization reactions can be used to steer the product distribution. For instance, in a 50 g scale batch reactor, the product obtained at 420 °C (only oil) is much lighter than at 500 °C (mixture of oil and wax), which can be attributed to the much lower evaporation rate of larger cracking products at 420 °C as a result of which these fragments crack further in the reacting liquid phase. [ABSTRACT FROM AUTHOR]

Development of simultaneous nitrification, denitrification and phosphorus removal (SNDPR) is a promising approach for domestic wastewater treatment. Mixed carbon sources by sodium acetate and glucose at various ratios (3:1, 1:1, and 1:3) were investigated to evaluate the effects on the sequencing batch reactors (SBR) based on aerobic granules. Results revealed that the mixed carbon did not change the settleability of aerobic granules, while glucose was more favorable for biomass retention induced by heterotrophs. Both carbon and ammonia nitrogen removal remained unaffected, while increased residual nitrate and phosphorus were detected with higher glucose ratios. Growing percentages of glucose led to more production of extracellular polymeric substances (EPS), especially polysaccharides (PS). Shifts of compositions of EPS were observed by the three-dimensional exaction and emission matrix (3D-EEM) fluorescence spectroscopy. MiSeq pyrosequencing technology demonstrated that the increasing ratios of glucose reduced the diversity of microbial community, though the dominant microbes remained unchanged. Phylogenetic classification of key groups involved in carbon, nitrogen and phosphorus removal suggested that mixed carbon source decidedly shaped the bacterial community. [ABSTRACT FROM AUTHOR]

Landfill leachate is a typical refractory wastewater that contains high concentration of organic pollutants. In this work, we investigated the treatment of landfill leachate by supercritical water oxidation (SCWO) in a batch reactor. The effects of temperature ( T , 450–600 °C), oxidation coefficient (OC, 1.2–3.4), reaction time ( t , 60–600 s) and pH (4.13–8.05) on total organic carbon (TOC) removal efficiency (TRE,%) and ammonia nitrogen (NH 3 -N) removal efficiency (NRE,%) were analyzed. TRE and NRE increased remarkably with increasing temperature and OC. At 3.4 OC and 600 °C, 92.5% TRE and 50.9% NRE were achieved after 600 s. A modified kinetic model on TRE and NRE considering the induction time was developed and accurately correlated the experimental results. A significant co-oxidation effect of methanol and landfill leachate in SCWO was detected. Furthermore, heterogeneous catalysts were added to SCWO of landfill leachate to improve the removal rate of organic contaminants. A series of composite catalysts (CeMnO x /TiO 2 ) which consisted of the cerium, manganese and titanium oxides were prepared by impregnation method with varying Ce/Mn ratio. Compared with the SCWO of leachate without catalyst, the CeMnO x /TiO 2 catalyst with Ce/Mn ratio of 1:2 exhibited high catalytic activity and stability. Additionally, a catalytic reaction mechanism was proposed. It was assumed that MnO x is the active component and CeO 2 is the additive and oxygen supplier. The results obtained from this work suggest the SCWO with high-efficiency and stable catalyst could be a promising technology for landfill leachate treatment. [ABSTRACT FROM AUTHOR]

Competition for electrons among different steps of denitrification on intracellular polymers (X STO ) plays a significant role in nitrous oxide (N 2 O) accumulation in the biological nitrogen removal process. In this work, this electron competition was considered in a mathematical model to predict N 2 O production in anaerobic/anoxic/oxic sequencing batch reactors (A 2 O-SBR) for the first time. The affinity constant for intracellular polymers of heterotrophs ( K STO ) that was used in previously published models was divided into four affinity constants ( K STO , 1 , K STO , 2 , K STO , 3 and K STO , 4 ) to represent the ability of each denitrification reductase to compete for intracellular polymers. The improved model was calibrated and validated using experimental data from three independent A 2 O-SBR systems. The results demonstrated that the modeling predictions strongly agreed with the measured data from all experimental tests under various operational conditions. The modeling results indicated that N 2 O accumulation resulted from the more rapid decline of the N 2 O reduction rate than the nitrite reduction rate for the inadequate X STO in these A 2 O-SBR systems. The modeling results also suggested that distinguishing affinity constants for intracellular polymers during the four-step denitrification felicitously described a different X STO distribution in each reduction step, thereby better predicting nitrogen dynamics and N 2 O production in A 2 O processes than the published model. The improved model is therefore a preferable tool to gain insight into N 2 O accumulation in A 2 O processes. [ABSTRACT FROM AUTHOR]

The present study investigates the performance of a new configuration laboratory-scale bioreactor comprising of two regimes (anaerobic & aerobic) in one reactor with physical separation and it is known as integrated anaerobic/aerobic sequencing batch reactor (IAASBR). The IAASBR is designed for treating high-strength wastewater such as poultry slaughterhouse wastewater (PSW) along with the simultaneous removal of organic carbon and ammoniacal nitrogen (NH 3 -N). The IAASBR exhibits that the average removal efficiency of total COD (TCOD), soluble COD (SCOD), NH 3 -N, fat, oil & grease (FOG), and total suspended solids (TSS) were (97% ± 2%), (95% ± 3%), (98% ± 1.3%), (90% ± 11%), and (96% ± 3%) respectively. The laboratory comparison test revealed that IAASBR configuration has enhanced the sludge settle-ability for aerobic SBR more than the conventional SBR or settling tank. Furthermore, IAASBR could tolerate the shock loading occurrence, handle organic loading rate (OLR) up to 4.5 kg (TCOD) m −3 d −1 and produce a high-quality effluent complying with Malaysian standards of industrial’s effluents. [ABSTRACT FROM AUTHOR]

Methylation of 2-methylnaphthalene (2-MN) under high-pressure reaction conditions over MTW-type zeolites (Si/Al = 100) was carried out using a batch-type reactor. Compared with macro-sized MTW-type zeolites, nano-sized MTW-type zeolites exhibited higher 2-MN conversion and dimethylnaphthalene (DMN) selectivity. In addition, coke formation on the catalyst could be suppressed due to improvement of the produced DMN solubility by increasing the bulk phase pressure, which enabled kinetic analysis of 2-MN methylation over MTW-type zeolites. Kinetics analysis of 2-MN methylation over MTW-type zeolites with different crystal sizes was successfully carried out, and reaction rate constants and activation energies for methylation and isomerization of 2-MN over MTW-type zeolites were obtained. The apparent reaction rate constants of 2-MN methylation were improved by decreasing MTW-type zeolite crystal size due to decrease in diffusion resistance. Moreover, the effectiveness factors for methylation of 2-MN were estimated based on the rate constants of 2-MN methylation and crystal sizes of the MTW-type zeolites. As a result, it was revealed that the crystal size of MTW-type zeolite (Si/Al = 100) required for methylation of 2-MN to achieve the reaction-limiting condition was below 240 nm. [ABSTRACT FROM AUTHOR]

• Continuous and green aerobic oxidation of ethylbenzene to acetophenone. • The space–time yield for the aerobic EB oxidation is about 2 order of magnitude larger than that of batch reactors. • Aerobic EB oxidation kinetic analysis was determined in a micro-packed bed system. • Chemical bonding tightly anchors NHPI on the surface of functionalized ACs. Aerobic oxidation of ethylbenzene (EB) has emerged as a promising strategy for the selective synthesis of acetophenone (AP) in line with green chemistry. The integration of flow chemistry into the pharmaceutical industry has been facilitated by recent advancements in microreactor technology. In this work, a continuous micro-packed bed reactor platform is developed to determine the kinetics of aerobic EB oxidation in the presence of N-hydroxyphthalimide (NHPI). The microreactor system offers enhanced gas–liquid mass transfer, leading to a 2-order-of-magnitude increase in the space–time yield of EB oxidation compared to traditional batch reactors. Furthermore, the organic catalyst NHPI is covalently anchored on commercial activated carbon through an imidization reaction. The synthetic heterogeneous catalysts exhibit excellent performance in terms of AP yield of 87.4 % and TOF value of 2.21 h−1 for continuous aerobic EB oxidation. [ABSTRACT FROM AUTHOR]