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A strong economic foundation can be achieved by the growth of a number of businesses, including food, paper, clothes, leather, and textiles. However, because of improper waste management, industrialization and modernization have resulted in the massive disposal of water effluent laden with harmful substances like dyes and heavy metals, which has negatively impacted the ecosystem. A new green technology called myco-remediation has emerged to battle harmful toxins while promoting sustainable development effectively and economically. This review employed enzymatic degradation, biosorption, and their influencing parameters for optimization in order to highlight the invaluable potential of fungal bioremediation for dye degradation. Current perspectives on enzyme immobilization techniques and kinetic studies of dye removal have been reviewed, which can aid in the selection of quick and effective removal processes. This research offers new insight into a criterion that is often overlooked in favor of dye decolorization efficiency: the toxicity assessment of pure dye and post-process metabolites produced following myco-remediation. Our attention has been directed towards toxicity analysis at many levels, including genotoxicity, phytotoxicity, and zoo-toxicity. This is important to keep in mind when considering the extensive implications of myco-remediation for the recycling and reuse of industrial effluent. Enzyme engineering and omics technologies have been highlighted as potential future developments. [ABSTRACT FROM AUTHOR]

Safranin is widely used in textile industries, and its discharge makes the effluent harmful to the environment. In this study, peanut shell biochar after chemical and thermal activation was coated with silica nanoparticles to make novel SiAcPNS 1:10 and was used to remove safranin dye present in solution. Detailed characterization of the nanocomposite was done using various equipment. The effect of different parameters was studied and adsorption isotherm, kinetics, and thermodynamic studies were done. Data derived from adsorption confirms Freundlich isotherm fitted best with R2 value of 0.995. The highest adsorption capacity was 19.646 mg.g−1. Furthermore, the negative ΔG value calculated from the thermodynamic study indicated that the process was spontaneous. Kinetic studies indicated that the adsorption followed the pseudo-second-order model. Experimentally, the highest removal of 97.22% was observed with the adsorbent dosage of 2 g.L−1, initial dye concentration of 10 mg.L−1, at 303 K, pH 8, and agitation speed of 130 rpm. Further optimization of the batch study was performed by response surface methodology (RSM). [ABSTRACT FROM AUTHOR]

The European Union regards gallium as a crucial element. Because of that, the retrieval of gallium ions from secondary sources through diverse methodologies is of the utmost significance in an actual economical context. The primary goal of this study was to explore the viability of MgFe2O4 spinel as an adsorbent material for Ga(III) ions recovery from aqueous solutions. A spinel adsorbent material was synthesised by using the sol–gel synthesis method. After preparation, the obtained spinel was subjected to a thermal treatment, which resulted in modifications of its crystalline structure and morphology, in concordance with the calcination temperatures. Specifically, two distinct temperatures of 260 and 650 °C were utilised in the process, which was conducted in air. The second objective was represented by the physicochemical characterisation of the newly prepared adsorbent material by using various analytical techniques, e.g., Fourier transform infrared spectroscopy (FT-IR), atomic force microscopy (AFM) and magnetic measurements. The optimal conditions for Ga(III) adsorption were established (S:L ratio, solution pH, contact time, temperature, initial Ga(III) concentration). Simultaneously, the obtained experimental data were modelled to prove the fact that the pseudo-second-order model explained the studied kinetics process and established its mechanism. Intraparticle diffusion was also studied to highlight the rate-determined step during the Ga(III) adsorption process. The equilibrium of the process was also studied, establishing that the Sips isotherm fitted the experimental data best, with a correlation coefficient R2~1, indicating that the studied adsorption process was homogeneous, the maximum adsorption capacity of spinel being 24.7 mg Ga (III)/g MgFe2O4. Thermodynamic parameters, involving ΔG°, ΔH° and ΔS°, were also calculated; negative values of ΔG° indicated that the adsorption was spontaneous. ΔH° proved to be endothermic, and the calculated ΔS° values being positive confirmed the fact that the process was spontaneous. [ABSTRACT FROM AUTHOR]

Large‐scale hydrogen production through water splitting represents an optimal approach for storing sustainable but intermittent energy sources. However, water oxidation, a complex and sluggish reaction, poses a significant bottleneck for water splitting efficiency. The impact of outer chemical environments on the reaction kinetics of water oxidation catalytic centers remains unexplored. Herein, chemical environment impacts were integrated by featuring methylpyridinium cation group (Py+) around the classic Ru(bpy)(tpy) (bpy=2,2'‐bipyridine, tpy=2,2′ : 6′,2′′‐terpyridine) water oxidation catalyst on the electrode surface via electrochemical co‐polymerization. The presence of Py+ groups could significantly enhance the turnover frequencies of Ru(bpy)(tpy), surpassing the performance of typical proton acceptors such as pyridine and benzoic acid anchored around the catalyst. Mechanistic investigations reveal that the flexible internal proton acceptor anions induced by Py+ around Ru(bpy)(tpy) are more effective than conventionally anchored proton acceptors, which promoted the rate‐determining proton transfer process and enhanced the rate of water nucleophilic attack during O−O bond formation. This study may provide a novel perspective on achieving efficient water oxidation systems by integrating cations into the outer chemical environments of catalytic centers. [ABSTRACT FROM AUTHOR]

This study investigates the pyrolysis kinetics behaviour and temperature effects on biochar yield and properties during pyrolysis. The kinetic study of biomass was performed using a thermogravimetric analyser at dynamic heating rates (10, 30, and 50 °C min−1) in an inert atmosphere. The kinetic parameters were estimated using Kissinger-Akahira-Sunose (KAS), Distributed Activation Energy Model (DAEM), and Vyazovkin model (VZ). The pyrolysis experiment was performed in a stainless steel semi-batch reactor at 400, 600, and 900 °C, 10 oC min-1 heating rate, 45 min holding time and 100 mL min−1 nitrogen gas flow rate. The produced biochar was characterised using proximate analysis, ultimate analysis, heating value, bulk density, BET surface area analyser, TGA, FTIR, and FE-SEM analysis. The physicochemical results support the candidacy of biomass for biochar and fuel production. Further, the kinetic analysis of MWS using KAS, DAEM, and VZ was found to be 233.39, 238.11, and 224.74 kJ mol−1, respectively. The experimental results reveal that higher temperatures (600 and 900 °C) generally reduce biochar yield (19 %) due to increased devolatilization but enhance the biochar's surface area (17 %) and carbon content (4.84 %). The characterisation results of biochar confirmed higher carbon content (76.02 wt. %), HHV (36.97 MJ kg−1), and significant oxygen content (22.01 %) at 900 °C. Also, the thermal profile and surface morphology of the biochar suggest that biochar derived at 600 and 900 °C can be used for carbon-based applications, whereas biochar derived at 400 °C can be used for soil amendment or fertiliser applications.

This comprehensive study explores the kinetics of adsorption and its photocatalytic degradation of methyl orange (MO) using an advanced copper-decorated photocatalyst in the form of hollow fibers (HFs). Designed to boost both adsorption capacity and photocatalytic activity, the photocatalyst was tested in batch experiments to efficiently remove MO from aqueous solutions. Various isotherm models, including Langmuir, Freundlich, Sips, Temkin, and Dubinin–Radushkevich, along with kinetic models like pseudo-first and pseudo-second order, Elovich, Bangham, and Weber–Morris, were utilized to assess adsorption capacity and kinetics at varying initial concentrations. The results indicated a favorable MO physisorption on the nanocomposite photocatalyst under specific conditions. Further analysis of photocatalytic degradation under UV exposure revealed that the material maintained high degradation efficiency and stability across different MO concentrations. Through the facilitation of reactive oxygen species generation, oxygen played a crucial role in enhancing photocatalytic performance, while the degradation process following the Langmuir–Hinshelwood model. The study also confirmed the robustness and sustained activity of the nanocomposite photocatalyst, which could be regenerated and reused over five successive cycles, maintaining 92% of their initial performance at concentrations up to 15 mg/L. Overall, this effective nanocomposite photocatalyst structured in the form of HF shows great promise for effectively removing organic pollutants through combined adsorption and photocatalysis, offering valuable potential in wastewater treatment and environmental remediation. [ABSTRACT FROM AUTHOR]

The development of mild strategies to transform of fructose to prepare high-purity 5-hydroxymethylfurfural (HMF) is of great significance for biomass valorization, and the design of an efficient catalytic approach is crucial. Herein, a mild catalytic strategy was developed to achieve the preparation of high-purity HMF from fructose over Amberlyst-15 catalyst in a water-methyl isobutyl ketone (MIBK) biphasic system under atmospheric pressure and lower temperature (90 °C). The catalytic system was optimized and analyzed by response surface methodology and kinetics study. Results indicated that a 46.6% yield of HMF could be obtained under optimal conditions: 80 wt% Amberlyst-15 catalyst, the mass ratio of MIBK to H2O 10, and the reaction time of 7 h. Furthermore, a simple and efficient purification strategy of HMF was established. High purity (99.0%) and recovery rate (65.5%) of HMF were obtained. This work provides an efficient catalytic strategy to produce high-purity HMF from fructose under atmospheric pressure and lower temperature. [ABSTRACT FROM AUTHOR]

The primary focus of the current investigation was to assess the removal of Rhodamine B dye (RhB) from aqueous solutions using pomegranate peel as a green adsorbent. The chemical and morphological characterization of pomegranate peel was conducted through ATR-FTIR spectroscopy and SEM microscopy. The study also investigated various reactional parameters, kinetic, and adsorption isotherm in a batch system. The results revealed that RhB adsorption reaches equilibrium in about 2 hours, with an adsorption capacity of 19.41 mg/g observed at a 50 mg/L of initial RhB concentration. To model the kinetic of RhB adsorption, two well-known models (pseudo-first-order and pseudo-second-order) were applied. The pseudo-second-order model yielded a superior fit for the kinetic data, as evidenced by analyses of R2, RMSE, ARE, and χ² values. Additionally, the findings suggest that the adsorption process is not solely governed by intraparticle diffusion. Furthermore, isotherm analysis revealed that the Langmuir model offered a more accurate fit to the equilibrium data, estimating the maximum removal capacity to be 47.17 mg/g. These findings suggest that pomegranate peel offers a promisingly eco-friendly and cost-effective solution for sustainable remediation of textile dyeing effluents. [ABSTRACT FROM AUTHOR]

This study explores the impact of varying temperatures on the release behavior of Triptorelin Acetate (TA) from a PLGA-based in-situ forming implant (ISFI) and polymer degradation. Formulations were prepared using the in situ forming method in an acetate buffer (pH = 6.8) and then exposed to temperatures of 4 to 60 °C. The drug release and polymeric depot behavior were evaluated using HPLC, SEM, GPC, Rheometer, and pH measurements. A modified Gallagher-Corrigan Model-based mathematical model was applied to fit the in-vitro data, and the activation energy for peptide release in diffusional and erosional phases was calculated using the Arrhenius equation. The results revealed that matrices formed at 37, 45, and 53 °C exhibited a highly porous structure, resulting from rapid phase inversion and surface pore closing. This led to a reduction in TA burst release, observed as 38%, 27%, and 15% at 37 °C, 45 °C, and 53 °C respectively. Conversely, matrices at 4 and 25 °C demonstrated a faster initial release, followed by the formation of dense structures. The accelerated drug release profiles at 45 and 53 °C showed a shortened ultimate drug release duration and a good correlation with the real-time results at 37 °C. Due to the discernible PLGA matrices degradation at different temperatures, biphasic and tri-phasic release patterns were observed. The experimental release results aligned well with the proposed mathematical model, and the drug release kinetic parameters were estimated. Thus, in in-vitro studies, the release medium temperature plays a significant role in the drug-release behavior of ISFIs. [ABSTRACT FROM AUTHOR]

The removal of cadmium for the treatment of contaminated wastewater was investigated using a natural local pozzolan clay excavated from the Laayoune region of Morocco. The adsorbent was characterized using different techniques, such as FTIR, SEM, BET, and XRD. Adsorption experiments were conducted under various operational parameters, where the results showed the following optimal conditions: temperature of 25 °C, pH value 6, and the adsorbent mass of 0.05 g for a 50 mg L−1 initial cadmium concentration. It was found that under these optimal conditions, the high adsorption percentage was 95.4%. The adsorption process shows a strong correspondence with a pseudo-second-order kinetic model with an R2 of 0.998. The experimental data closely matched the Langmuir isotherm model with R2 and Qm values of 0.989 and 166.67 mgg−1, respectively. The obtained thermodynamic parameters (ΔG °, ΔH °, and ΔS °) showed a spontaneous and endothermic elimination process. The adsorption configurations of cadmium (II) ions onto the SiO2 (111) surface, which is the major component of the investigated pozzolan, were explored using Monte Carlo simulation. The theoretical part aims to explain and facilitate the understanding of the adsorption mechanism through the calculated adsorption energy (kcal mol−1) of the Cd2+ ion on the surface of SiO2 (111) in gaseous and aqueous phases. [ABSTRACT FROM AUTHOR]

The aim of this review is to understand the progress in waste material management through pyrolysis to produce eco-energy. The growing demand for energy, combined with the depletion of traditional fossil fuels and their contribution to environmental problems, has led to the search for waste-to-energy technologies in pursuit of carbon neutrality. While municipal residues are only part of the waste management problem, the impact of discarded plastics on the environment and landfills is significant. Plastics not only take centuries to decompose, but also seriously pollute the oceans. Pyrolysis is a thermochemical process that allows for the thermal decomposition of waste in the absence of oxygen. There are several types of pyrolytic reactors, including batch and continuous ones. Batch reactors are preferred to process polymeric waste, with studies highlighting the importance of optimizing parameters, i.e., type of feedstock, heating rate, and pyrolysis temperature. Moreover, the choice of reactor type can influence the yield and structure of the final compounds. Furthermore, various studies have highlighted the gas heating value obtained through waste pyrolysis and how the composition of the liquid fraction is influenced by the type of polyethylene used. Though scientific interest in pyrolysis is remarkable, as publications have increased in recent years, kinetics studies are scarce. Overall, pyrolysis is a promising technique for managing waste materials to produce energy. Ongoing research and development in this area offer significant potential for improving the sustainability of waste management systems. [ABSTRACT FROM AUTHOR]

In this work, poly(α-methyl styrene) (PAMS) was synthesized through living anionic polymerization and characterized by 13C NMR, 1H NMR, GPC, TGA, DSC. The kinetics study was performed using multi-stage dosing of initiator. The results obtained via GPC analysis revealed that polydispersity index of the synthesized PAMS was close to the true value. Moreover, multi-stage dosing of initiator offers valuable and accurate method to determine propagation rate constant and initial impurities value of the system. 13C NMR analysis demonstrated that Bernoullian statics model exhibits a superior fit compared to 1st -order Markov statics model for the assigned sequence. Furthermore, the synthesized PAMS presents higher degree of racemic addition with Pm=0.439. 1H NMR spectroscopy was utilized to ascertain number-average molecular weight of the synthesized samples, corroborating the values estimated through GPC analysis. From the thermal analysis, it was shown that PAMS containing very low molecular weight demonstrates negative glass transition temperature and broad thermal decomposition range. [ABSTRACT FROM AUTHOR]

A fully continuous-flow nitration and post-processing protocol has been introduced into the preparation of 4-nitropyrazole. The process started from the nitration reaction of pyrazole with mixed acid, followed by continuous quenching, neutralization, extraction and separation. After the collected organic phase was rotationally evaporated to recover the solvent, the final product 4-nitropyrazole was obtained with 96.9% yield, 99.3% purity and 381 g/h productivity. By establishing a kinetics model and MATLAB simulation calculation, it worked out to achieve the preferable selectivity conditions of mono-nitration product 4-nitropyrazole. The process of post-processing solved the problems of solid precipitation and extractant hydrolysis. The extraction process was determined by the distribution coefficient and twice extraction was used to reduce the amount of organic solvent. [ABSTRACT FROM AUTHOR]

Fish wastes and vegetable market wastes generated along with other wastes in the urban cities are disposed of in open landfill sites and lead to water, air and soil pollution. It occupies more and more land area for disposal as the generation of waste also increases day by day. In this current study, a novel approach has been identified to recover energy from mixed fish waste (MFW) and vegetable market waste (VMW) by anaerobic co-digestion. In fish waste, more than 75% of the total solids contribute to volatile solids, indicating that waste content is organic and suitable for anaerobic digestion. Further, MFW showed that the protein content is 4 to 5 times higher than carbohydrate content, indicating nitrogen richness will inhibit the AD process. Hence, co-digestion of MFW with carbon-rich VMW to maintain the stability of AD has been carried out. In this batch study, the biogas potential of these organic nitrogen-rich wastes was evaluated for major fish species (Parastromateus niger, Sillago indica and Scomberomorus cavalla) and mixed fish wastes individually and co-digestion of MFW with vegetable market waste (VMW) in different ratios. Based on the results, the specific biogas yields from Parastromateus niger, Sillago indica, Scomberomorus cavalla and mixed fish waste were 0.301 ± 0.011, 0.291 ± 0.002, 0.306 ± 0.008 and 0.289 ± 0.013 L/g of VS added, respectively. The co-digestion of fish waste with vegetable market waste in different mixing ratio (1:1 to 1:5) showed specific biogas yields of 0.445 ± 0.02 (1:1), 0.462 ± 0.01 (1:2), 0.489 ± 0.013 (1:3), 0.454 ± 0.015 (1:4) and 0.432 ± 0.011 (1:5) L/g of VS added. The results showed that there is an increase in biogas production during the co-digestion process confirming the synergistic potential of fish waste and vegetable market as substrates for the anaerobic digestion process. Further, the cumulative biogas production data were modelled using first-order kinetic, modified Gompertz and logistics models. The model results showed that the logistics model fitted well with experimental data (R2 of 0.99) and the predicted values from this model were less than 1% deviation from experimental biogas production. The results confirmed the suitability of anaerobic digestion for co-digestion of MFW and VMW for enhanced energy recovery for future implementation in an urban area to reduce the waste dumped in landfills. [ABSTRACT FROM AUTHOR]

A new sol-gel method that employs cation exchange from an aqueous metal ion solution with H+ ions of granulated alginic acid was developed for synthesizing high-purity Y2O3 nanoparticles. In this study, the cation exchange kinetics of H+~Y3+ in aqueous solution were analyzed using on-line pH technology and off-line inductively coupled plasma-atomic emission spectrometry (ICP-AES) analysis. Pseudo 2nd-order models were utilized to evaluate the parameters of the kinetics, suggesting that the concentration of H+~Y3+ involved in the cation exchange reaction was 1:1.733. Further, a comprehensive understanding of the Y-ALG calcination process was developed using thermo-gravimetric analysis, along with results obtained from differential scanning calorimetry (TGA/DSC). A detailed analysis of the XRD Rietveld refinement plots revealed that the crystallite sizes of Y2O3 nanoparticles were about 4 nm (500 °C) and 15 nm (800 °C), respectively. Differential pulse voltammetry (DPV) was employed to investigate the electrochemical oxidation of catechol. The oxidation peak currents of catechol at Y2O3 (500 °C)/GCE and Y2O3 (800 °C)/GCE showed two stages linear function of concentration (2.0~20.0 × 10−6 mol/L, 20.0~60.0 × 10−6 mol/L). The results indicated that the detection limits were equal to 2.4 × 10−7 mol/L (Y2O3 (500 °C)/GCE) and 7.8 × 10−7 mol/L (Y2O3 (800 °C)/GCE). The study not only provided a method to synthesize metal oxide, but also proposed a promising on-line pH model to study cation exchange kinetics. [ABSTRACT FROM AUTHOR]

The demand for lithium-ion batteries (LIBs) is driven by environmental concerns and market growth, particularly in the transportation sector. The EU's push for net-zero emissions and the European Green Deal accentuates the role of battery technologies in sustainable energy supply. Organic acids, like gluconic acid, are explored for the eco-friendly leaching of valuable metals from spent batteries. This study investigates leaching kinetics using gluconic acid (hydrolyzed glucono-1.5-lacton), analyzing factors such as temperature, acid concentration, particle size, and reaction time. Results reveal the temperature's influence on leaching efficiency for cobalt, nickel, and lithium. The mechanism for Co follows a surface chemical reaction model with an activation energy of 28.2 kJ·mol−1. Nickel, on the contrary, shows a diffusion-controlled regime and an activation energy of 70.1 kJ·mol−1. The reaction of leaching Ni and Co using gluconic acid was determined to be first-order. The process within this environmentally friendly alternative leaching agent shows great potential for sustainable metal recovery. [ABSTRACT FROM AUTHOR]

This study explores the bioactive compound extraction from laurel (Laurus nobilis L.) leaves using a pulsed electric field (PEF) as a standalone extraction technique. The primary parameters impacting the extraction process were optimized through response surface methodology. Specifically, solvent composition (ethanol and water mixtures) and liquid-to-solid ratio, along with other key PEF conditions (i.e., electric field intensity, pulse period, and pulse length) were examined. The antioxidant capacity was evaluated through DPPH and FRAP assays, whereas total polyphenol content was also measured. A comparison was also made between the extracts produced with and without PEF. The results showed that after 30 min of extraction, the best parameters were a pulse period of 355 μs, a pulse duration of 55 μs, and an electric field intensity of 0.6 kV/cm. A liquid-to-solid ratio of 10 mL/g was chosen, whereas the best solvent was determined to be 25% (v/v) ethanol/water mixture. The PEF-treated extract contained 77% more polyphenols compared to the untreated sample. In addition, PEF-treated samples had a rise of up to 288% for certain individual polyphenols. Correlation analyses also revealed interesting trends among bioactive compounds and the antioxidant capacity of the extracts. The effect of the investigated parameters on polyphenol recovery was demonstrated, indicating that comparable investigations should consider these parameters to optimize polyphenol extraction yield. Regarding green and non-thermal standalone techniques, PEF outshines other extraction techniques as it could also be used as a sustainable way to swiftly generate health-promoting extracts from medicinal plants. [ABSTRACT FROM AUTHOR]

Ammonium salt vanadium precipitation process has excellent performance in industrial production, but its shortcomings such as high cost and environmental impact are not conducive to sustainable development. In this paper, ethylenediamine was selected as the precipitant, and vanadate was precipitated from acidic simulated vanadium-rich solutions by the ammonium salt precipitation process. The high purity V2O5 product was obtained after calcination. Under optimal conditions, the precipitation rate of vanadium reached 94.8 %, and the purity of vanadium was as high as 99.1 %. The vanadium precipitation product was hexamethyl ammonium, and the vanadium product was V2O5. It can be derived by the differential method that the reaction order was n = 2.4, the reaction rate equation was CV-1.4=kt+a, and the apparent activation energy was 27.8097 kJ/mol, which can be classified as the diffusion-controlled reaction. This innovative process enables a savings of 5050 yuan per ton of V2O5. On this basis, a complete V2O5 production process with zero waste discharge was designed.

Purifying water for diverse uses is vital, but concerns lie with the sustainability and accessibility of purification materials. As such, this study converted readily available water treatment plant sludge (WTPS) into activated adsorbent for phosphate removal in wastewater. WTPS was activated via thermal activation at 300 °C temperature and chemical activation processes of 3 M acid concentration, 4 h activation time, and 75 °C activation temperature, and then characterized using Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), Fourier transform infrared, elemental analyzer, and differential scanning calorimetry. SEM and BET analyses revealed a highly porous adsorbent (279.2 m2/g) for efficient adsorption. On top of the activation process, preliminary experiments and numerical optimization using response surface methodology (RSM) were designed and conducted. Through optimizing conditions, it was found that 70 min of contact time, pH 3, 3 g/L adsorbent dose, and 30 mg/L initial phosphate concentration as optimal, yielding 83% removal efficiency. Furthermore, adsorption kinetics and isotherm models were examined and the second-order kinetics and Langmuir isotherm models indicated best fit. Notably, the activated sludge could be regenerated for three cycles before efficiency dropped below 70%. Thus, activated WTPS presents a promising, sustainable, and readily available adsorbent for phosphate removal in wastewater treatment. HIGHLIGHTS Water treatment plant sludge (WTPS) was activated through thermal activation and chemical activation.; The activated WTPS adsorbent has a surface area of 279.2 m2/g.; The activated WTPS showed an 83% removal efficiency.; The regeneration test indicated that the activated sludge can be used three times, repeatedly, before its efficacy falls below 70%.;

The presence of persistent organic compounds in wastewater poses significant challenges to both biotic community and natural environment, resulting in a severely adverse effect on the ecosystem. In view of the urgent scenarios, the removal of pollutants from wastewater effluent has a significant potential to restore ecological equilibrium and maintain the social value of sustainability. Among the various methods used for wastewater treatment, photocatalytic advanced oxidation processes have gained as a viable and promising alternative approach. The objective of this review paper is to provide a comprehensive exploration of the various photocatalytic materials used in wastewater treatment with potential scopes for future enhancements. Further, various factors affecting the removal of pollutants from wastewater are highlighted. In particular, the selection, design aspects and scaleup criteria of photocatalytic reactors could assist in the establishment of commercial scale process. This review stimulates research on the kinetic study in order to get a deeper understanding of the mechanisms involved in the formation of novel photo-catalyst materials. Thus, photo catalytic advanced oxidation process could become as a spectacular treatment method for wastewater.

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Adsorption of samarium(III) on a weakly macroporous cation exchanger Amberlite IRC-50 (H+) and (Na+) forms is studied as a function of the initial pH of the aqueous solution, time and temperature, initial samarium(III) ion concentration, and the amount of resin at a fixed temperature (20 ± 1 °C). The concentration range was between 0.1-5 mmol/L, the pH range was between 1.8 and 10.5; the stirring time was between 2 and 60 min; and the amount of resin was between 0.025 and 0.15 g. Both the film and particle diffusion equations are applied to explain the kinetic data. The rate constant values for samarium(III) adsorption were calculated for both film and particle diffusion processes. It is observed to follow the order (Na+) > (H+). Temperature is found to have an insignificant effect on both diffusional processes. Various thermodynamic parameters (ΔH°, ΔS°, and ΔG°) from samarium(III) exchange on the resin were calculated. The optimum conditions were found to be a concentration of 1 mmol/L, pH of 9.3, stirring time of 20 and 5 min for Amberlite IRC-50 (H+) and (Na+) forms, respectively, and 0.15 g of resin. The equilibrium extraction of samarium was 22.2 mg/g for Amberlite IRC-50 (H+) and 21.9 mg/g for Amberlite IRC-50 (Na+) at an initial concentration of 1 mmol/L. The results obtained show that the Amberlite IRC-50 weak cation-exchange resin performed well for the removal and recovery of samarium(III). The optimization procedure provides access to industrial-scale Sm(III) removal processing. [ABSTRACT FROM AUTHOR]

Coffee is the most essential drink today, aside from water, the high consumption of coffee and the byproducts of its soluble industries such as spent coffee grounds can have a negative effect on the environment as a source of toxic organic compounds. Therefore, caffeine removal from the spent coffee ground can be applied as a method to limit the effect of its production on the environment. The aim of this study is to determine the kinetics and thermodynamics parameters and develop models for both processes based on the process parameters by using traditional solid-liquid extraction and Ultrasound-assisted extraction methods. The processes were performed at a temperature range of 25 to 55 °C for traditional and ultrasound baths, and experimental time ranged from 5- 60 min. The results demonstrated that under the above conditions, the extraction process applies to the pseudo-first-order reaction, where the rate constant K value increases with temperature. The transition state parameters were also discussed where these parameters indicated that the system of the process exhibited an activated complex formation state resulting in a thermodynamically unfavorable process, and the thermodynamic parameters at the equilibrium state were also evaluated in terms of the obtained yield percentage. The results also showed that the ultrasound-assisted bath process showed a spontaneous behavior at temperatures of 45 °C and 55 °C with D°G of -1192.9703 and - 2725.25 J/mole. On the other hand, for the traditional method, the extraction process was approaching a spontaneous behavior with the temperature increasing where at 25 °C the D°G value was 10379.944 J and at a temperature of 55 °C it reached 8004.26 J/mole.

This study presents two environmental aspects: valorisation of natural oil shale (NOS), on the one hand, and, on the other hand, to study the effectiveness of adsorption of methylene blue (MB) dye onto material (NOS). In this context, the most characterisations of adsorbent before and after adsorption process were investigated by several methods such as x-ray diffraction (XRD), scanning electronic microscopy (SEM) and Fourier transforms infrared spectrometry (FTIR), according to these results, the NOS is rich in quartz and calcite, the matrix clay contains the kaolin and illite and present a layer structure. The total number of results showed that the adsorption of MB onto NOS is best by pseudo-second-order fitting model with a good correlation (R2 = 0.98), on the other hand the adsorption process was described well by Langmuir isotherm with a maximal capacity of adsorption equal 29 mg/g. The effect of temperature on the adsorption of the dye was also evaluated and the thermodynamic parameters were determined. The negative values of the three thermodynamic parameters ΔH °, ΔG ° and ΔS ° of the NOS/MB system indicate that the adsorption is spontaneous, exothermic and the activated energy indicates that the adsorption mechanism might be a physical sorption process. [ABSTRACT FROM AUTHOR]

The efficiency of ZnCl2-activated cocoa pod husk charcoal (ACPHC) in removing Pb(II), Cu(II) and Cd(II) ions from aqueous solution was investigated under different conditions of shaking speed, contact time, adsorbent dose, adsorbate concentration, pH, and temperature with a view to widening the applications of the husk. Adsorption equilibrium, kinetics and desorption studies were conducted. Activated carbon produced at 650 °C was found to give the best desired properties. The optimum shaking time and pH value were 45 min and 6. The shaking speed of 700 rpm gave maximum removal efficiency (mean ± sd) 97.02 ± 0.34%, 96.24 ± 0.19%, and 96.85 ± 0.01% for Pb(II), Cu(II), and Cd(II) ions at the optimum pH, 25 °C, and 0.1 g adsorbent/25 ml solution with adsorption capacities of 2.426, 2.406, and 2.421 mg/g, respectively. While the average capacity at the optimum contact time was 2.290 mg/g. Non-linear Temkin and Redlich–Peterson and linear Langmuir isotherm models gave the best description of the adsorption equilibrium of the metal ions onto ACPHC surface, while pseudo-second order kinetics model gave the best description of the adsorption kinetics. The rate of removal of the metal ions was in the order Pb(II) > Cu(II) > Cd(II). The regeneration of the spent adsorbent was efficient with respect to the considered metal ions. The recovery values were 96.72 ± 0.43%, 92.76 ± 0.49%, and 91.66 ± 0.34% for Pb(II), Cu(II), and Cd(II) ions, respectively. Thus ACPHC was found to be an efficient low-cost material for the removal of the studied metal ions from aqueous solution. [ABSTRACT FROM AUTHOR]

In the ozonation process, the phenol degradation in wastewater undergoes a low mass transfer mechanism. In this study, ozonized packed bubble column reactor was designed and constructed to remove phenol. The reactor’s inner diameter and height were 150 and 8 cm, respectively. The packing height was kept constant at 1 m in accordance with the reactor hydrodynamics. The gas distributor was designed with 55 holes of 0.5 mm. The phenol removal efficiency was evaluated at ozone concentrations of 10, 15, and 20 mg/L, contact times of 15, 30, 45, 60, 75, 90, 105, and 120 min, and phenol concentrations of 3, 6, 9, 12, and 15 mg/L. The results indicated that the highest phenol removal efficiency of 100% was achieved at 30 min in presence of packing. Moreover, the use of packing improved the contact between the gas and liquid, which significantly enhanced the phenol degradation. Actually, a thin film over a packing surface enhances the mass transfer. Also, it was found that the phenol is degraded into CO2 and H2O through a series of reaction steps. Additionally, a kinetic study of a first-order reaction provided an efficient estimation of reaction parameters with a correlation factor of 0.997.

The relevance of the study is caused by the need to develop new methods for the disposal of metal waste. This direction, with the participation of various intensifying influences, refers to resource-saving, technological, minimizing the volume of capital costs for raw materials, production and subsequent sales. Purpose: to study physical and chemical methods for alkaline and acid processing of aluminum waste in the field of ultrasound, consider the mechanisms of these processes, compare kinetic characteristics, identify the pros and cons of the methods, and, based on a comparative analysis, conclude which of the methods is the most effective. Objects: samples of aluminum waste in the form of plates and shavings. Methods: volumetry, sonochemical synthesis, evaluation and analysis of the kinetic curves of the process at different temperatures, X-ray phase analysis. Results. The analysis of kinetic curves, rate constants of processes at different temperatures, and orders of chemical reactions has been carried out. The values ​​of the activation energies of the target chemical reactions and the characteristics of the kinetic regions of the processes were compared with each other. Despite the long induction period, the kinetic potential of acid processing of aluminum waste turned out to be 2 times higher than that of alkaline processing at temperatures of 313–323 K. Ultrasonic radiation did not significantly affect this characteristic, although it reduced the induction effect by 2 times. The mechanisms of the ongoing sonochemical processes in these methods turned out to be very similar to each other, no fundamental differences were observed. The products obtained during chemical processing in the form of hydrogen, hydroxide, chloride and aluminum orthophosphate are currently in high demand in the energy, chemical and silicate industries, as well as in medicine.

Alkyd coatings incorporated with different types of micronutrients were successfully prepared and coated on granular urea. Three sets of micronutrients, Zn(NO3)2·6H2O and borax, ZnO and borax, and ZnAl-layered double hydroxide, were studied. The water solubility of micronutrients plays an important role to produce different pore sizes and control the release rate of macro- and micronutrients. The coated urea granules were characterized by using FE-SEM technique, and micronutrient distribution on coating films was performed using energy-dispersive X-ray spectroscopy. Zn, B, and nitrogen releases were evaluated in DI water according to the ISO 21263. The nutrient release kinetics was determined by comparing the data with zero-order, first-order, Higuchi (HG), Hixson–Crowell (HC), and Korsmeyer–Peppas (KP) kinetic models. The diffusion release of Zn micronutrient showed the best fit with KP model, and the diffusion release of boron (B) micronutrient was consistent with HG model. The release characteristics of the nitrogen from urea core through coating films could be best described by the KP model. These coating films are the enhancement of controlled-release fertilizers to reduce the environmental implications imposed by excessive use of fertilizers for a long-term period. [ABSTRACT FROM AUTHOR]

The demand for lithium-ion batteries (LIBs) is driven by environmental concerns and market growth, particularly in the transportation sector. The EU’s push for net-zero emissions and the European Green Deal accentuates the role of battery technologies in sustainable energy supply. Organic acids, like gluconic acid, are explored for the eco-friendly leaching of valuable metals from spent batteries. This study investigates leaching kinetics using gluconic acid (hydrolyzed glucono-1.5-lacton), analyzing factors such as temperature, acid concentration, particle size, and reaction time. Results reveal the temperature’s influence on leaching efficiency for cobalt, nickel, and lithium. The mechanism for Co follows a surface chemical reaction model with an activation energy of 28.2 kJ·mol−1. Nickel, on the contrary, shows a diffusion-controlled regime and an activation energy of 70.1 kJ·mol−1. The reaction of leaching Ni and Co using gluconic acid was determined to be first-order. The process within this environmentally friendly alternative leaching agent shows great potential for sustainable metal recovery.

The relevance of the study is caused by the need to develop new methods for the disposal of metal waste. This direction, with the participation of various intensifying effects, refers to resource-saving, technological, minimizing the volume of capital costs for raw materials, production and subsequent sales. Purpose: to study the physical and chemical laws of aluminum waste acid processing in the field of ultrasound, propose a mechanism for this process, and, based on the established laws and the proposed mechanism, develop a method for aluminum waste acid processing to obtain reaction products that are in demand in the industry. Objects: samples of aluminum waste in the form of plates and shavings. Methods: volumetry, differential thermal analysis, evaluation and analysis of the kinetic curves of the process at different temperatures. Results. The kinetic curves were analyzed, the rate constants of the process at different temperatures were calculated, and the order of the chemical reaction was found. Based on the calculated activation energy of the process, a characteristic was given about the kinetic region of the process. The mass content of aluminum in the samples was found. According to the data obtained, exposure of the system to ultrasound contributed to an increase in the rate of the chemical process by 90 % at 303 K; by 5 % at 313 K. The process itself began within 10...30 seconds and completed within a few minutes, which confirms the possibility of recycling aluminum waste using acid solutions at low temperatures. The resulting hydrogen can be used in hydrogen energy, since it is the only gaseous product of the reaction, which eliminates the need for its purification before transportation. The aluminum chloride solution synthesized during the reaction can be used in wastewater treatment, wood processing, production of antiperspirants, as well as precipitated aluminum phosphate and used in the ceramic industry.

Active metal-based materials (AMMs) as CO 2 sorbents or oxygen carriers (OCs) have been investigated to enhance hydrogen production during various biomass-based chemical looping processes. CaO-based sorbents and Fe-based OCs are widely used in this field; therefore, these two types of materials will be the focus of this review. CaO-based sorbents can promote the water-gas shift reaction towards H 2 generation with in-situ CO 2 removal. OCs partly oxidise biomass, releasing CO – a reactant in the water-gas shift reaction. The use of Fe-based OCs boosts H 2 yield via iron-steam reactions. AMMs possess catalytic activity for tar cracking, generating more H 2. However, these AMMs suffer from sintering over cycles, which hinders their utilisation at industrial scales. The addition of support materials aims to overcome this issue. This review first assesses the impacts of CaO sorbents and OCs on H 2 production, and then examines the material behaviour, cyclic performance and applications in biomass-based chemical looping processes. The mechanism of support materials as a reactivity enhancer and sintering inhibitor is proposed in the review. The effects of operating conditions on H 2 yield are summarised and provided in the Supplementary materials. • AMMs can enhance H 2 production in biomass gasification processes. • CaO-based sorbents and Fe-based OCs are commonly used in biomass steam gasification. • Integrated calcium looping and redox cycle is a promising process. • Addition of support materials in AMMs can overcome the sintering-related issues. • Effects of operation conditions are assessed in the Supplementary materials. [ABSTRACT FROM AUTHOR]

This study reports the removal of chromium (VI) from waste aqueous medium using disilver-dicopper oxide nanoparticles (Ag2Cu2O3 NPs) as adsorbent, which were synthesized by adopting reduction route of chemical method and stabilized by emulsifier (sodium dodecyl sulfate [SDS]). Synthesized nanoparticles were further characterized using different analysis techniques such as UV–Vis for the detection of NPs via Λmax and their point-zero charge (pzc) determination also done. Whereas, FTIR and XRD were done to determine the functional groups, crystal plane (tetragonal) and crystallite size (15.19 nm) of Ag2Cu2O3 NPs respectively. SEM was used with EDX for morphology and elemental confirmation respectively. The synthesized nanoparticles were then employed for the adsorptive removal of chromium (VI) (Cr(VI)). Different parameters including pH, temperature, agitation time, adsorbate and adsorbent's concentration were also studied. At optimized conditions, 0.5 g adsorbent, 40 ppm concentration of Cr(VI) solution along with 1 h agitation time were studied. Maximum observed adsorption and chromium removal efficiency was 96.66319 %. Four adsorption isotherms namely; Freundlich, Langmuir, Temkin and Harkins-Jeura were employed from which Freundlich adsorption model gives best fitting on experimental results. The kinetic modelling had shown that adsorption process follows second order kinetics. The thermodynamic studies of the adsorptive removal of Cr(VI) also evaluated. The Ag2Cu2O3 NPs adsorbent's reusability were also determined. The study had proven that Ag2Cu2O3 nanoparticles are efficient adsorbents for the removal of Cr(VI). [ABSTRACT FROM AUTHOR]

This study is aimed to model and optimize the decolorization of reactive black 5 (RB5) dye using Bacillus albus DD1. The response surface methodology (RSM) along with rotatable central composite design (rCCD) is used to optimize the response, % decolorization with four input variables: (i) pH (5–9), initial dye concentration (50–500 ppm), the composition of yeast extract as nitrogen source (0.2–1%) and amount of bacterial inoculum (5–25% v/v). The % decolorization is predicted to be ≈ 98% at the optimized condition (pH = 7.6, dye concentration = 200 ppm, bacterial inoculum = 20 v/v% and yeast extract = 0.4%). Furthermore, the kinetics and thermodynamics of RB5 degradation are also determined. The kinetic order of biodegradation of RB5 is found to follow first-order kinetics with a kinetic rate constant = 0.0384. The activation energy, Ea and frequency factor, A values are calculated as 34.46 kJ/mol and 24,343 (1/Day). A thermodynamic study is also carried out at different temperatures (298 K, 308 K, 310 K, 313 K, and 318 K) using optimized conditions. The values of the and ΔS are found to be +30.79 kJ/mol, and −0.1 kJ/mol/K, respectively using the Eyring–Polanyi equation. The values of ΔG are also calculated at all temperatures. HIGHLIGHTS RSM with rCCD is employed to optimize the decolorization of reactive black 5 using a novel bacterial strain.; Optimization of process parameters such as pH, yeast extract as a co-substrate, amount of bacterial inoculum and initial dye concentration.; Under optimized conditions, 98% removal was achieved within 72 hr.; The values of kinetic and thermodynamic parameters k, Ea, A, ΔH and ΔS are estimated.;

Glyphosate (N-phosphonomethyl glycine) is a non-selective, broad-spectrum organophosphate herbicide. Its omnipresent application with large quantity has made glyphosate as a problematic contaminant in water. Therefore, an effective technology is urgently required to remove glyphosate and its metabolites from water. In this study, calcium peroxide nanoparticles (nCPs) were functioned as an oxidant to produce sufficient hydroxyl free radicals (·OH) with the presence of Fe2+ as a catalyst using a Fenton-based system. The nCPs with small particle size (40.88 nm) and high surface area (28.09 m2/g) were successfully synthesized via a co-precipitation method. The synthesized nCPs were characterized using transform infrared spectroscopy (FTIR), X-ray diffractometry (XRD), Brunauer–Emmett–Teller analysis (BET), dynamic light scattering (DLS), and field emission scanning electron microscopy (FESEM) techniques. Under the given conditions (pH = 3.0, initial nCPs dosage = 0.2 g, Ca2+/Fe2+ molar ratio = 6, the initial glyphosate concentration = 50 mg/L, RT), 99.60% total phosphorus (TP) removal and 75.10% chemical oxygen demand (COD) removal were achieved within 75 min. The degradation process fitted with the Behnajady–Modirshahla–Ghanbery (BMG) kinetics model. The H2O2 release performance and proposed degradation pathways were also reported. The results demonstrated that calcium peroxide nanoparticles are an efficient oxidant for glyphosate removal from aqueous systems. [ABSTRACT FROM AUTHOR]

In this study, sawdust-based nanocomposite was synthesized from sawdust biochar and surface coating of the biochar was done using silica nanoparticles. Removal of hexavalent chromium (Cr(VI)) was studied using the synthesized nanocomposite. The adsorption capacity of the coated biochar was found as 88.2 mg/g for chromium removal. The mechanism of adsorption process was estimated using both adsorption isotherm and kinetic models. The pseudo-second-order kinetic model was capable of showing the possible mechanism behind the adsorption process. Linear and nonlinear pseudo-second-order model was analysed and the result was compared and error analysis of this study with experimental results was done using correlation coefficient (r2) and chi-square (χ2) test. With higher r2 and low χ2value 0.999 and 0.2947, respectively, the nonlinear form of pseudo-second-order kinetic model was able to describe the adsorption process more successfully than the linear form. Category 1 of the linear form was a good approximation with nonlinear analysis. The ANN model was also developed and the model was validated with the experimental study. [ABSTRACT FROM AUTHOR]

Background: Italy can augment its profit from biorefinery products by altering the operation of digesters or different designs to obtain more precious bioproducts like volatile fatty acids (VFAs) than biogas from organic municipal solid waste. In this context, recognizing the process stability and outputs through operational interventions and its technical and economic feasibility is a critical issue. Hence, this study involves an anaerobic digester in Treviso in northern Italy., Objective: This research compares a novel line, consisting of pretreatment, acidogenic fermentation, and anaerobic digestion, with single-step anaerobic digestion regarding financial profit and surplus energy. Therefore, a mass flow model was created and refined based on the outputs from the experimental and numerical studies. These studies examine the influence of hydraulic retention time (HRT), pretreatment, biochar addition, and fine-tuned feedstock/inoculum (FS/IN) ratio on bioproducts and operational parameters., Methods: VFA concentration, VFA weight ratio distribution, and biogas yield were quantified by gas chromatography. A t test was then conducted to analyze the significance of dissimilar HRTs in changing the VFA content. Further, a feasible biochar dosage was identified for an assumed FS/IN ratio with an adequately long HRT using the first-order rate model. Accordingly, the parameters for a mass flow model were adopted for 70,000 population equivalents to determine the payback period and surplus energy for two scenarios. We also explored the effectiveness of amendments in improving the process kinetics., Results: Both HRTs were identical concerning the ratio of VFA/soluble chemical oxygen demand (0.88 kg/kg) and VFA weight ratio distribution: mainly, acetic acid (40%), butyric acid (24%), and caproic acid (17%). However, a significantly higher mean VFA content was confirmed for an HRT of 4.5 days than the quantity for an HRT of 3 days (30.77, SD 2.82 vs 27.66, SD 2.45 g-soluble chemical oxygen demand/L), using a t test (t8=-2.68; P=.03; CI=95%). In this research, 83% of the fermented volatile solids were converted into biogas to obtain a specific methane (CH4) production of 0.133 CH4-Nm3/kg-volatile solids. While biochar addition improved only the maximum methane content by 20% (86% volumetric basis [v/v]), the FS/IN ratio of 0.3 volatile solid basis with thermal plus fermentative pretreatment improved the hydrolysis rate substantially (0.57 vs 0.07, 1/d). Furthermore, the biochar dosage of 0.12 g-biochar/g-volatile solids with an HRT of 20 days was identified as a feasible solution. Principally, the payback period for our novel line would be almost 2 years with surplus energy of 2251 megajoules [MJ] per day compared to 45 years and 21,567 MJ per day for single-step anaerobic digestion., Conclusions: This research elaborates on the advantage of the refined novel line over the single-step anaerobic digestion and confirms its financial and technical feasibility. Further, changing the HRT and other amendments significantly raised the VFA concentration and the process kinetics and stability., (© Hojjat Borhany. Originally published in JMIRx Med (https://med.jmirx.org).)

Background & aim: Today, the production of effluents containing medicinal compounds, including tetracyclines, is one of the major threats to the environment and endanger human health. Accordingly, the need for an efficient system to remove these compounds from aquatic environments is felt. Therefore, the aim of this study was to optimize and model the removal of tetracycline antibiotics using TiO2 / N / S nanocatalyst in the presence of visible light in aqueous solutions. Methods: In this experimental study conducted in 2019, nanocatalyst was synthesized by sol-gel method and then its characteristics were analyzed using SEM, XRD, EDS and BET analyzes. Secondly, by changing the reaction conditions such as changing the synthesized photocatalyst dose (0.1-2) g/l, antibiotic concentration (1-50) mg/l, reaction time (2-90) minutes and solution pH (2-10) and by visible light irradiation to remove tetracycline from synthetic effluent and the effect of these variables on process performance by response surface method and CCD method and determination of optimal conditions, investigation of reaction kinetics, tetracycline mineralization and photocatalyst performance in real wastewater treatment Was evaluated. Tetracycline was determined by reverse phase high performance liquid chromatography (HPLC). The collected data were analyzed using analysis of variance. Results: The software has proposed a complete quadratic model as the best model, based on ANOVA analysis of variance. The maximum removal efficiency of tetracycline with this process in optimal conditions with a pH of 6 and a time of 56 minutes and a concentration of tetracycline of 13 mg/l was the catalyst value of 1.2 g/l was 77%. The mineralization efficiency of tetracycline antibiotics under optimal conditions was 47% and the kinetic study presented that the data followed the quasi-first-order model well and eliminate the tetracycline process in the wastewater of Imam Sajjad Hospital of Yasuj by 72%. Conclusion: The results indicated that the efficiency of TiO2/N/S photocatalytic process exposed to visible light radiation in the removal of tetracycline due to lack of by-products as well as mineral end products (carbon dioxide and water) as a desirable process.

This article presents, in detail, the paths and mechanisms, main by-products, and a kinetic study of the oxidation of profenofos (PFF) by HO• radicals. Photo-assisted peroxidation was the precursor reaction for generation of radicals; the effect of UV-C (245 nm) radiation was evaluated. The results of the kinetics study indicated that the best fit for the experimental data was the pseudo-first-order model; further, that oxidation occurs in a fast initial stage and a slow final stage. In an acidic environment, the fast oxidation stage was favored over the slow stage; while in the basic medium the opposite behavior was observed. Eight oxidation by-products and 29 reaction intermediates were identified. The main mechanisms involved in the mineralization of PFF were reactions of electron abstraction, HO• abstraction, H• abstraction, substitution, displacement, and addition of electrons. The rapid oxidation step was related to the mining of the O–C2 H5 and S–C3 H7 chains of the intermediate O-ethyl S-propyl phosphonothioate. The slow oxidation step included the mineralization of 4-bromo-2-chlorophenyl and derivatives. [ABSTRACT FROM AUTHOR]

The current study explored the bioenergy potential of waste miscanthus grass (WMG). The kinetic study of WMG was evaluated via two model-free methods, in a thermogravimetric analyzer (TGA), at dynamic heating rates under an inert ambiance. The pyrolysis was performed in a semi-batch fixed bed reactor at 500 oC, 80 oC min heating rate, and 1 mm particle size. The evolution of hot vapours during pyrolysis was explored using a TGA-FTIR analyzer. Finally, the bio-oil and biochar were characterized by their physicochemical properties. The kinetic results established that WMG followed a multi-step decomposition process, and the average activation energy gained from KAS and ST was found to be 197.66 and 179.64 kJ mol-1, respectively. TGA-FTIR study revealed the foremost release of carbon dioxide (28.22%), followed by a carbonyl (25.40%), and ether (19.12%). Further, the pyrolysis of WMG yielded 29.32 wt% of bio-oil at the optimized condition whereas, physicochemical results of bio-oil established; 65.16% carbon content, 26.16 MJ kg-1 HHV, 34.15 cP viscosity, and 812 kg m-3 density. GC-MS study of bio-oil confirmed the maximal release of hydrocarbons and phenols. Finally, characterization results of miscanthus grass biochar (MGB) demonstrated an excellent feedstock for industrial and domestic applications. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, different calorimetric and analytical techniques were used to evaluate the thermal behavior of the preparation of 1‐nitronaphthalene through the nitration of naphthalene with mixed acid. Differential scanning calorimetry and adiabatic calorimetry revealed that 1‐nitronaphthalene lacks thermal decomposition characteristics. The results of reaction calorimetry, high‐performance liquid chromatography, and the density function theory method were combined to analyze the reaction mechanism. An expanded Stoessel criticality diagram was developed to evaluate the process safety of the semibatch nitration reaction. The results revealed a higher degree of risk than that obtained when using the traditional Stoessel criticality diagram. Kinetics parameters of the reaction were investigated. [ABSTRACT FROM AUTHOR]

Adsorption of anthraquinone dye Acid Blue 111 by alumina-iron oxide doped particles prepared by sol-gel method from aqueous solutions was studied. The adsorbent morphology was revealed by FESEM and the crystallographic phase is analyzed by the XRD technique. The effect of adsorbate and adsorbent concentrations, pH value, type of adsorbent and thermodynamic parameters on dye removal by adsorption was studied. The change of dye concentration during the adsorbtion was followed using the UV-Visible spectrophotometer. The change of the adsorbent surface before and after dye removal was observed using the Fourier Transformation-infrared spectroscopy (FT-IR). The adsorption kinetics is in accordance with the pseudo-second-order kinetics model. The Langmuir and Freundlich adsorption isotherm models were used to describe the adsorption process. The thermodynamic study of dye adsorption proves the process is spontaneous with exothermic nature.

In the current investigation, the capacity of different yeast strains to decolorize reactive black 5 (RB-5) was assessed. A comparative study between the different strains demonstrated that Saccharomyces cerevisiae X19G2 exhibited the highest decolorization rate (69.20 ± 1.16%) after 48 h of incubation. This strain was selected to optimize the medium components' concentrations for maximum RB-5 decolorization. Response-surface methodology (RSM) was tested for the most significant parameters (glucose, yeast extract and RB-5 dye concentrations) that were previously determined by Plackett–Burman design. A dye decolorization rate of 99.59 ± 0.24% was achieved within 48 h using a maximum RB-5 concentration (0.15 g/L) with glucose and yeast extract concentrations equalling to 10.5 g/L and 1 g/L, respectively. Experimental data results proved to fit well with the pseudo-second order kinetics model. The phytotoxicity assessment was carried out using Raphanus sativus seeds to determine the toxicity of RB-5 before and after treatment by S. cerevisiae. Results suggested that germination rate and the length of seeds radical irrigated with 0.15 g/L of RB-5 decreased by 30 and 53%, compared to those irrigated with treated solution. Therefore, metabolites derived from decolorization of RB-5 by S. cerevisiae X19G2 were significantly less toxic than the original dye. [ABSTRACT FROM AUTHOR]