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The serious environmental risks caused by Pb(II) and Sb(V) co-contamination increase the need for their efficient and simultaneous removal. In this study, the remediation feasibility by Fe-doped phosphogypsum (FPG) was elucidated for single systems with Pb or Sb pollutant and coexisting systems with both from water. As for single systems, Fe doping effectively enhanced the Pb(II) removal performance by phosphogypsum (PG) at low Pb(II) concentrations of below 100 mg/L via the combination of precipitation and complexation. The optimal removal rate of Sb(V) by FPG increased by 2.08-3.31 times as compared to that of by PG (10-120 mg/L), mainly due to the strong affinity of iron hydroxyl (≡Fe-O-H) towards Sb(V). Compared with the single systems, the coexistence greatly enhanced the Pb(II) and Sb(V) removal performance by FPG, and the interaction behavior between Pb(II) and Sb(V) on the FPG was concentration dependent. Briefly, the sorption of FPG controlled the elimination of low coexisting concentrations of Pb(II) and Sb(V), whereas the co-precipitation process between Pb(II) and Sb(V) predominated with high ions concentration. The significant synergistic effects were found during the removal of Pb(II) and Sb(V) on FPG in the coexisting system, which mainly attributed to precipitation, bridging complexation and electrostatic attraction. Considering the advantages such as facile preparation, low cost and high removal capacity, FPG is a promising material to uptake Pb(II) and/or Sb(V) from contaminated water.

Candida albicans is an important human fungal pathogen. Our previous study disclosed that aryloxy-phenylpiperazine skeleton was a promising molecule to suppress C. albicans virulence by inhibiting hypha formation and biofilm formation. In order to deeply understand the efficacy and mechanism of action of phenylpiperazine compounds, and obtain new derivatives with excellent activity against C. albicans, hence, we synthesized three series of (1-heteroaryloxy-2-hydroxypropyl)-phenylpiperazines and evaluated their inhibitory activity against C. albicans both in vitro and in vivo in this study. Compared with previously reported aryloxy-phenylpiperazines, part of these heteroaryloxy derivatives improved their activities by strongly suppressing hypha formation and biofilm formation in C. albicans SC5314. Especially, (9H-carbazol-4-yl)oxy derivatives 25, 26, 27 and 28 exhibited strong activity in reducing C. albicans virulence in both human cell lines in vitro and mouse infection models in vivo. The compound 27 attenuated the virulence of various clinical C. albicans strains, including clinical drug-resistant C. albicans strains. Moreover, additive effects of the compound 27 with antifungal drugs against drug-resistant C. albicans strains were also discussed. Furthermore, the compound 27 significantly improved the composition and richness of the faecal microbiota in mice infected by C. albicans. These findings indicate that these piperazine compounds have great potential to be developed as new therapeutic drugs against C. albicans infection.

Developing new catalysts for efficient degradation of micropollutants in water is of significant importance in advanced oxidation processes (AOPs). Herein, TiO

Upon contacting with water, cold plasma should produce numerous ozone molecules and free electrons at room temperature. In this study, a cold plasma generator was used to break the walls of residual activated sludge obtained from domestic sewage. The impact was mainly influenced by the ozone generated. With 800 W power, sludge wastewater pH of 12.0, and under continuous treatment for 10 h, the system's reduction efficiency for the dry sludge was ≈90%. Furthermore, the organic matter content (especially protein) of the upper layer of the sludge solution increased a lot after the sludge digestion. This observation proved the reduction of sludge from both sides. Moreover, when the cold plasma technique was compared with thermal acid hydrolysis, thermal alkali hydrolysis, and ultrasonication for extracting protein from activated sludge, cold plasma wall-breaking sludge exhibited the highest efficiency, reaching 38.2% under ambient temperature. After the analysis, the toxic metal content in the extracted protein was near zero, which is a level other protein extraction methods via sludge breaking have not achieved to date, we attribute this efficiency to free electrons the cold plasma produce. These species promote the transformation of metal ions into atomic metals, thereby facilitating their removal.

The co-application of biochar and fertiliser has emerged as a strategy for improving soil quality and crop growth, however, the impact of the type of fertiliser added with biochar to the soil on leaching and retention of nutrients is not well studied. In this study, a leaching experiment was undertaken using a series of column lysimeters incorporating a wheat straw biochar (WSB) and two fertiliser types—chemical fertiliser (CF), or rock mineral fertiliser (MF). The results showed that CF and MF leached a similar amount of NH4+ with or without WSB, but the NO3– leaching occurred from CF-treated soil which was decreased by CF + WSB application. In contrast, NO3– leaching was not affected by WSB in MF-treated soil. Both CF and MF with or without WSB increased the cumulative leaching of P and K. Nevertheless, WSB application increased soil P and K contents after leaching, which was attributed to intrinsic nutrient release from biochar. Shoot growth and P and K uptake also increased with biochar amendment, whereas root growth and N uptake did not change. Therefore, the results highlight that biochar addition can improve nutrient retention and plant growth by reducing nutrient leaching, mainly dependent on biochar and fertiliser type combination used. It suggests that the adsorption properties of biochar for nutrient retention and subsequent release need to know before their broad application to soils as amendments.

In this study, ozonation catalyst nano-MnO

Development of efficient catalysts for peroxymonosulfate (PMS) activation and further understanding its mechanism on organic pollutants degradation is of significant importance for advanced oxidation processes (AOPs). Herein, hollow (Co, Mn)3O4 catalysts were synthesized by calcination of Co, Mn containing metal-organic frameworks (MOFs) and further used to evaluate the effectiveness of organic pollutants (Bisphenol A (BPA), atrazine (ATZ), and diethyl phthalate (DEP)) degradation by PMS activation. The PMS utilization efficiency in (Co, Mn)3O4/PMS system (36.4%) was estimated to be 28.0% and 43.8% higher than that of Co3O4/PMS and Mn5O8/PMS system, respectively. Notably, the metal leaching in (Co, Mn)3O4/PMS system was significantly suppressed. The utilization efficiency also reveals an inverse proportionality relationship with BPA mineralization but decreases with increasing initial pH value. A synergy between oxides of Co and Mn was perceived to enhance PMS utilization efficiency and BPA degradation. The results indicate enhanced catalytic performance with (Co, Mn)3O4 compared to Co3O4 derived from Co-MOF and other reported catalysts, with 99% of BPA degradation within 4 min. The oxidation mechanism was then proposed based on the electron paramagnetic resonance (EPR) and XPS results. Our findings might have contributed to designing heterogeneous catalysts for efficient PMS utilization in AOPs.

Effective removal of Sb(III) and Sb(V) has long been an urgent task for protecting human health and environment. In this study, novel magnetic mesoporous FeMn binary oxides (MMFMs) were fabricated via calcinating the Mn encapsulated carboxymethyl cellulose-Fe(III) hydrogel, and the structure of MMFMs were closely related to the Fe:Mn ratio. Owing to the mesoporous structure together with synergistic effect of FeMn binary component, the MMFMs exhibited excellent mass transfer and adsorption ability to Sb(III) and Sb(V). MMFM

Well dispersed nanocatalysts on porous substrate with macroscopic morphology are highly desired for the application of heterogeneous catalysis. Traditional fabrication process suffers from multiple steps for controlling the structure on nanocatalysts and matrix or both. Herein, we report a facile strategy for the synthesis of millimeter-sized hierarchical porous carbon beads (HPCBs) which containing well dispersed hollow-nano carbon boxes for peroxymonosulfate catalysis. Specially, the precursors of HPCBs were prepared by phase inversion method, which involving introduction of zeolitic imidazolate framework (ZIF-8) nanocubes into polyacrylonitrile (PAN) solutions followed by solidification of the mixture. After pyrolysis, nitrogen doped and hierarchical porous HPCBs with diameter of about 1.2 mm were obtained. The merits of our synthesis strategy lie in that synchronizes the hollow microstructure evolution with the shaping of ZIF-8 nanocubes into millimeter scale beads. Attribute to its special structure feature and the appropriate chemical composition, the resultant millimeter-sized HPCBs exhibit enhanced catalytic performance by activation of peroxymonosulfate (PMS) for tetracycline degradation. The degradation efficiency of TC is up to 85.1% within 120 min, which is 18% higher than that of ZIF8-Solid/PAN carbon bead (SPCBs). In addition, the possible decomposition pathways, main reactive oxygen species, and reasonable enhanced mechanism for the HPCBs/PMS system are systematically investigated by quenching experiments, electron paramagnetic resonance (EPR) and liquid chromatography-mass spectrometry (LC-MS). This work addresses the issue of easy aggregation and recycling of carbon materials in industrial productions and extends the prospects of carbon materials in engineering applications.

Considering the highly toxic by-products generation and environmental friendliness, the adsorption process is a suitable solution as the end of pipe treatment for refractory organics in coking wastewater. Nitrogen-doped micro-mesoporous carbon prepared by carbonization and KOH activation of urea-formaldehyde resin (UFCA) realized effective adsorption of quinoline, phenol and pyridine in coking wastewater. Among them, UFCA-900 has large specific surface area (SBET=1469.94 m2·g-1) and excellent adsorption properties: the adsorption removal rate of quinoline reached 98.40% about 16 min, and the maximum adsorption capacity of quinoline was 721.90 mg·g-1 at 318 K, the adsorption capacity of phenol and pyridine at 298 K were 341.59 mg·g-1 and 225.08 mg·g-1, respectively. The adsorption kinetics of UFCA-900 obeyed the pseudo-second-order model, and the adsorption process was endothermic. The membrane adsorption reactor demonstrated efficient adsorption, well separation, and negligibly irreversible membrane fouling. The adsorption mechanism included electrostatic interactions, π-π interactions and hydrogen bonds. Regeneration test proved that the removal rate of the chemically regenerated UFCA-900 was similar to the fresh adsorbent after six cycles. Taken together, a simple strategy for in-situ nitrogen-doped porous carbon has been developed and the resultant composite UFCA-900 has promising application prospect in coking wastewater treatment.

In this study, ozonation catalyst nano-MnO2 blended polyvinylidene fluoride (PVDF) membrane was fabricated via phase inversion method and applied to membrane bioreactors (MBR), and then coupled with in-situ ozonation to study the anti-biofouling performance and reveal its mechanism. Results showed that, compared with pristine PVDF membrane (MBR_M0), 0.75 wt% and 1.00 wt% nano-MnO2 modified PVDF membrane (MBR_M0.75 and MBR_M1.00) could mitigate the membrane biofouling rate. Meanwhile MBR_M1.00 coupled with in-situ ozonation could increase the membrane cleaning cycle to 1.5 and 2.7 times, compared with MBR_M0 and MBR_M0.75 without in-situ ozonation. The possible mechanisms included that the nano-MnO2 modification coupled with in-situ ozonation directly removed the biofouling on the membrane surface, improved the hydrophilicity of the membrane surface and enhanced the chemical oxidation and biodegradation of membrane biofouling contaminants in the sludge mixture. The results of this work provide a new strategy for the control of membrane biofouling in MBR to treat industrial wastewater.

Industrial wastewater containing organic ligands and heavy metals is considered a serious public health threat, and its treatment and purification have become challenging tasks. Moreover, the organic-chelated heavy metals formed by common organic ligands and free heavy metals can cause many problems and concerns because of their poor biodegradability, high solubility, and extreme stability. In this study, aluminum-containing ferrihydrite (Fh-Al) adsorbents of different composition molar ratios were prepared and utilized to remove typical EDTA-Cr(III) in an aqueous system, and the associated removal mechanism was examined. The experimental results show that adding Al not only enhances the removal rate of EDTA-Cr(III) by the Fh-Al adsorbent in a wide pH range (pH = 3–9) but also increases the maximum adsorption capacity of EDTA-Cr(III). In addition, the specific surface area of Fh-Al can be increased by adding aluminum with different molar ratios, thus promoting its adsorption performance for EDTA-Cr(III). Furthermore, surface complexation and electrostatic attraction were proposed as possible mechanisms of EDTA-Cr(III) adsorption by Fh-Al. This study shows that Fh-Al-6 adsorbent can adsorb common EDTA-chelated heavy metals (such as EDTA-Pb, EDTA-Cr, EDTA-Cu and EDTA-Cd) in one step, with maximum adsorption capacities of 41.47, 32.33, 16.51 and 31.27 mg/g at pH = 3. The Fh-Al-6 adsorbent can be reused after being regenerated in a 2 g/L Na2SO4 solution. This study provides new expectations for treating wastewater containing organic groups and heavy metals.

Efficient decontamination of Sb(V) from water has long been an urgent task owing to its grave threat to human health. Herein, Y-based MOFs (MOF-Y and NH2-MOF-Y) were synthesized for effective adsorption of Sb(V) from aqueous solution, and the stability of the Y based MOFs were estimated. Kinetic and isotherms results indicated that the pseudo-second order kinetic (R2 > 0.90) and Langmuir isotherm models (R2 > 0.97) quite well described the adsorption of Sb(V) on Y-based MOFs, revealed that the uptake of Sb(V) on Y-based MOFs were followed by a monolayer chemical adsorption process. The maximum adsorption capacities of Sb(V) calculated from the Langmuir model were 161.3 and 151.5 mg/g for MOF-Y and NH2-MOF-Y, respectively. The Y-based MOFs exhibited strong water and chemical stability, it could be utilized for removal Sb(V) under wide pH range and various concentration of Sb(V). The spent adsorbents could be successfully regenerated by NaCl (5 mol/L) solution for further utilization without damaging the crystal structure of Y-based MOFs. X-ray photoelectron spectroscopy (XPS) and energy dispersive spectroscopy (EDS) results revealed that the formation of inner-sphere Y-O-Sb complex between Y-oxo-clusters and Sb(V) was the dominant adsorption mechanism, while the co-precipitation of Y^(+3) and Sb(V) was also partially contributed the Sb(V) adsorption. High stability together with high Sb(V) adsorption capacity and excellent recyclability endow the Y-based MOFs as promising adsorbents for Sb(V) removal from wastewater. Refereed/Peer-reviewed

The interfacial compatibility between fillers and polymers essentially influences the separation performance of mixed matrix membranes (MMMs). In this work, an one-pot synthesized functional layer veiled zeolite imidazolate frameworks-67 (VZIF-67) was used as an efficient nanofillers to fabricate MMMs via physical blending with 6FDA-Durene polyimide. Benefiting from the CO2 affinity from functional layer and the intrinsic characteristics of porous nanofillers, significant enhancement on separation performance was observed on the resultant MMMs. Specifically, the optimized VZIF-67 MMMs (30 wt% loading) exhibited CO2/CH4 selectivity of 32.5 with CO2 permeability of 1210 Barrer, which is 1.7 and 1.5 times higher than those of the control membrane, respectively. More importantly, the surface organic attribute and abundant amine groups of VZIF-67 reinforced the interfacial compatibility between the nanofillers and polymer matrix, leading to a doubled CO2/CH4 selectivity compared with the ZIF-67 MMMs. Overall, the performance of the VZIF-67 membrane toward CO2/CH4 separation surpasses the 2008-updated Robeson upper bound. These results indicate the functionalization strategy on porous nanofillers is a promising approach to fabrication of high performance of MMMs.

EDTA-Cu(II) is usually observed in electroplating wastewater, and its removal is very challenging due to its easy dissolution, stability and difficult biodegradation characteristics. In this work, an excellent binary composite (MG) was prepared via the combination of green rust (GR) and MoS2 to remove EDTA-Cu(II) from an aqueous solution. Batch test results showed that the maximum capacity of EDTA-Cu(II) uptake by MG was 89.85 mg/g. Thus, up to 98.5% of EDTA-Cu (20 mg/L) was removed. The residual Cu content was lower than the discharge standard of China (0.5 mg/L); additionally, the leaching of Fe ions was lower than 22 mg/L under ambient conditions. MG could satisfactorily remove EDTA-Cu(II) from complex environments in one step and was only minimally affected by various experimental conditions (the presence of different salt ions, different ratios of EDTA organic groups, and different dissolved oxygen concentrations). The highly active MG composite has a wider pH range (pH = 3–7) for the efficient replacement reaction with EDTA-Cu(II) than for the replacement of common Fe(III) ions (pH = 2.7–5.2). GR deposited on MoS2 could not only effectively increase the surface reaction sites of MG composites but also enhance EDTA-Cu(II) removal performance through the mutual synergy between GR and MoS2. These experimental results suggest that MG holds promise for use in removing EDTA-Cu(II) from contaminated wastewater.

Achieving Cd removal standards is a difficult task due to the strict Cd discharge standards for industrial wastewater. Moreover, the low concentration of Cd remaining in industrial wastewater after pretreatment often exists in a complex state, and the wastewater has a high salinity. Hereupon, we propose to use a small amount of sulfur-modified zero-valent iron (S-NZVI) to remove residual low-concentration Cd complexes in high-salinity wastewater. EDTA-Cd (2000 μg/L) was completely removed when the dose of S-NZVI was only 0.05 g/L. Moreover, the removal process was almost unaffected by salinity. Even when the salinity was 5%, the adsorption capacity still reached 39.5 mg/g, and the concentration of residual Cd was less than 50 μg/L, which meets the China Environmental Protection Administration emission standards (less than 0.1 mg/L). In addition, S-NZVI can almost completely remove EDTA-Cd in the pH range of 2-7. It shows good removal performance for the other four Cd carboxyl complexes (DTPA, citrate, glycine, and tartrate). Furthermore, S-NZVI also shows good performance in the case of high concentrations of coexisting ions (CaCl2, MgCl2, Na2SO4, NaNO3) and organics (Na2EDTA, imidazole, thiourea, acetone). However, the performance of S-NZVI is certainly inhibited by the presence of complexing substances or reducing substances. The mechanism EDTA-Cd removal by S-NZVI is that S-NZVI leaches Fe3+ into the solution, and the Fe3+ completes the replacement of EDTA-Cd. The LMCT produced by EDTA-Fe under natural light promotes the replacement process, and finally, the released Cd2+ is captured by S-NZVI and removed as CdS and Fe-O-Cd.

During the boronic acid production process, boronic acid emission causes considerable loss of resources and water pollution. At present, adsorption is the preferred technology to treat boron pollution. Although conventional adsorbents are simple and effective, their regeneration and recovery are challenging, which hinder their wide-scale application. Considerable research efforts have been devoted to resolving the two issues mentioned above. Herein, a novel boron-adsorbing magnetic material with a cis-diol structure possessing boronate affinity was prepared. 3-Hydroxytyramine hydrochloride auto-polymerization (PDA), magnetic graphene oxide (GO) synthesis, polyethylenimine (PEI) self-assembly, and a 3,4-dihydroxyphenylpropionic acid (DHHA) covalent bonding procedure were conducted to synthesize a Fe3O4/PDA/GO/PEI/DHHA nanocomposite. This nanocomposite exhibited excellent adsorption performance and was easily recycled using an external magnetic force. The boronic acid was separated and recovered by simply adjusting the pH of the solution. The nanocomposite’s adsorption capacity reached 91.46 mg g-1 at 30 °C with 4-formylphenylboronic acid (FPBA) as a model compound. Besides, the adsorption capacity of the nanocomposite was maintained at >89% of its original value even after five cycles. It was confirmed that the adsorption was primarily a thermochemical reaction controlled by entropy change. Thus, this novel adsorbent can be used for boron removal because it exhibits significant boronate affinity and high regeneration ability and is easy to recycle.