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• 1,3-D degradation rate was U-shape related to biochar pyrolysis temperature. • Improving humidity or incubation temperature enhanced biochar catalytic ability. • 1,3-D degradation occurred through OH oxidation or pH-restricted substitution reaction. • Conversion of livestock manure into biochar was an attractive waste treatment method. The conversion of waste biomass into biochar is considered as a waste disposal alternative, especially because biochar is a low-cost adsorbent for soil contaminants. However, a risk of desorption of contaminants from biochar may lead to secondary pollution. This study investigated the degradation behavior of soil fumigant, 1,3-dichloropropne (1,3-D), on cow manure-derived biochar (CMB) pyrolyzed at five different temperatures from 300 to 700 °C (termed as C-300 to C-700). Results showed that 1,3-D degradation rate was U-shape related to biochar pyrolysis temperature. Four degradation byproducts (NH 2 CH 2 CH 2 CH 3 OH, CH 3 CH 2 NH 2 , NH 2 COCONH 2 , OHCH 2 COOH) were identified by headspace GC–MS. When biochar humidity improved from 0 to 50% or incubation temperature increased from 20 to 40 °C, the degradation of cis -1,3-D on C-300 improved 24.26% and 35.48%, respectively. The OH concentrations, detected by the terephthalic acid method, were considerably higher for C-300 than that for C-700. Pyrolysis temperature (300–700 ° C) governed biochar physicochemical properties and further affected 1,3-D degradation mechanisms (pH-controlled substitution or OH-restricted oxidation reaction). All these findings showed that CMB can adsorb and degrade 1,3-D, thereby reduce its desorption risk, indicative of the conversion of cow manure into biochar as an effective waste management practice. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • CuFeS 2 with abundant surface bonded ferrous were successfully prepared. • CuFeS 2 exhibits higher activity for PMS activation than Cu 2 S, FeS 2 and CuFeO 2. • S2− species promote the cycling of Fe3+/Fe2+ and Cu2+/Cu+ cycles on CuFeS 2 surface. • There is the synergistic effect of Fe-Cu cycles for PMS activation by CuFeS 2. Abstract Chalcopyrite nanoparticles (CuFeS 2 NPs) with abundant surface bonded ferrous were successfully prepared, characterized and used as a catalyst for peroxymonosulfate (PMS) activation and BPA degradation. The effect of reaction parameters such as initial pH, catalyst load, PMS concentration, initial BPA concentration and reaction temperature on BPA degradation in CuFeS 2 -PMS system was systematically investigated. As a bimetallic sulfide, CuFeS 2 exhibits ultra-high activity for PMS activation compared with Cu 2 S, FeS 2 , CuFeO 2 and Co 3 O 4. It was found that by co-use of 0.1 g L−1 CuFeS 2 and 0.3 mmol L−1 PMS, 20 mg L−1 of BPA was almost completely degraded (99.7%) and reached a mineralization rate of 75% within 20 min. The highly catalytic activity of CuFeS 2 is closely related to two aspects: one is that S2− in the catalysts promotes the cycling of Fe3+/Fe2+ and Cu2+/Cu+ cycles on the surface, and the other is the synergistic effect of Fe3+/Fe2+ and Cu2+/Cu+ cycles in the PMS activation. These interesting findings shed some new insight on the development of metal sulfides for the oxidative treatment of organic contaminants. [ABSTRACT FROM AUTHOR]

In this work, nitrogen-rich graphene-like carbon sheets (N-GLCS) with high specific surface area (488.4 m 2 /g), narrow pore distribution and high N-doping (18.4 at%) were prepared and applied as both adsorbent and catalyst for the removal of bisphenols. Adsorption experiments demonstrated the high adsorption capacities of the N-GLCS toward bisphenol F (BPF) (222.9 mg/g), bisphenol A (BPA) (317.8 mg/g), and bisphenol C (BPC) (540.4 mg/g). Results showed that about 98.6% of BPA (70 mg/L) was removed at pH 7.0 within 80 min after the adsorption-catalytic degradation process. The N-GLCS also showed a superb reusability for the catalytic oxidative degradation of BPA (70 mg/L) with the removal percentage maintains over 83% after 5 cycles. With the synergistic combination of the excellent adsorption and catalytic properties of the N-GLCS, trace amount of pollutants can be preconcentrated and immobilized at the surface of N-GLCs, at the same time, active radicals were also produced at the surface of the N-GLCS by the activation of peroxydisulfate (PS), and finally the pollutants can be degraded in-situ by the active radicals. These findings provide a new avenue towards the efficient removal of trace-level EDCs from water solution by using the coupled adsorption-advanced oxidation processes. [ABSTRACT FROM AUTHOR]

Iron nanoparticles (NPs) embedded in S, N-codoped carbon were prepared by one-step pyrolysis of a homogeneous mixture consisting of Fe, S, N, C precursors, and then immobilized in poly (vinylidene fluoride) membranes as a multifunctional catalytic system (NSC-Fe@PVDF) to effectively activate peroxymonosulfate (PMS) and oxidize organic compounds in water. The NSC-Fe@PVDF membranes effectively decolorized organic pollutants at a wide pH range (2.05-10.85), due to the synergistic effects between the S, N-doped carbon and iron NPs. The efficiency depended on the doping types, amount of metal, PMS dosages, reaction temperatures, solution pHs, and organic substrates. In-situ electron spin resonance spectroscopy and sacrificial-reagent incorporated catalysis indicate radical intermediates such as sulfate and hydroxyl radicals are mainly responsible for this persulfate-driven oxidation of organic compounds. Membrane’s porous structure and high internal surface area not only minimize the NPs agglomeration, but also allow the facile transport of catalytic reactants to the active surface of metal catalysts. The results demonstrate the morphological and structural features of catalytic membranes enhance the overall catalytic activity. [ABSTRACT FROM AUTHOR]

In recent years, researchers have devoted themselves to developing composites containing cobalt as highly active heterogeneous catalysts of persulfate. Most of them reported that the catalytic degradation processes of organic pollutants were accompanied by the leaching of cobalt ions, but only a few studies considered the contribution of the dissolved cobalt ion to the degradation of organic compounds. A research paper in Journal of Hazardous Materials reported a study on synthesis, application and catalytic mechanisms of cobalt doped hydroxyapatite (Co-HAP) for Rhodamine B (RhB) degradation. We find that non-main catalytic mechanisms were listed and that the effect of Co-HAP was overestimated. [ABSTRACT FROM AUTHOR]

β-Lactam antibiotics including penicillin G, nafcillin, cefazolin, cefotaxime, and oxacilline in water were rapidly removed and degraded by using didodecyldimethylammonium bromide (DDAB)-montmorillonite (MT) organoclay. Removal of antibiotics increased with increasing the amount of organoclay added and the amount of DDAB sorbed on MT. Extents of organoclay sorption of antibiotics were represented by the binding constants to DDAB molecules and correlated to the aqueous-octanol distribution coefficients. The degradation rate of β-lactam antibiotics was found to significantly increase by the organoclay sorption. Even under the mild conditions (25 °C and pH 7), penicillin G ( m / z = 335) nearly completely (>98%) degraded into penicilloic acid ( m / z = 353) missing β-lactam ring within 2 h. The first-order reaction rate of the primary degradation increased with increasing in temperature. The activation energy estimated from the Arrhenius plot was 49 kJ mol −1 and lower than the value (83.5 kJ mol −1 ) in water, strongly suggesting catalytic activity of DDAB-MT organoclay. The applicability to wastewater treatment was demonstrated by using secondary effluents of municipal sewage treatment plants and synthesized hospital wastewaters. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the catalytic degradation produced by laccase in the detoxification of glyphosate, isoproturon, lignin polymer, and parathion. We explored laccase-glyphosate, laccase-lignin polymer, laccase-isoproturon, and laccase-parathion using molecular docking (MD) and molecular dynamics simulation (MDS) approaches. The results suggest that laccase interacts well with glyphosate, lignin polymer, isoproturon, and parathion during biodegradation. We calculated the root mean square deviations (RMSD) of laccase-glyphosate, laccase-lignin polymer, laccase-isoproturon, and laccase-parathion as 0.24 ± 0.02, 0.59 ± 0.32, 0.43 ± 0.07, and 0.43 ± 0.06 nm, respectively. In an aqueous solution, the stability of laccase with glyphosate, lignin polymer, isoproturon, and parathion is mediated through the formation of hydrophobic interactions, hydrogen bonds, and van der Waals interactions. The presence of xenobiotic toxic compounds in the active site changed the conformation of laccase. MDS of the laccase-substrate complexes confirmed their stability during catalytic degradation. Laccase assay results confirmed that the degradation of syringol, dihydroconiferyl alcohol, guaiacol, parathion, isoproturon, and glyphosate were 100%, 99.31%, 95.69%, 60.96%, 54.51%, and 48.34% within 2 h, respectively. Taken together, we describe a novel method to understand the molecular-level biodegradation of xenobiotic compounds through laccase and its potential application in contaminant removal., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Membrane technique is a promising way for the removal of dyes from wastewater. A unique approach combining both the adsorptive and the catalytic membrane processes was proposed on the basis of a new functionalized membrane. The membrane integrating both the adsorptive and catalytic activities was developed by introducing polyoxometalates (POMs) as an ideal candidate for the membrane functionalization via a novel sol–gel method. A two-step protocol, adsorptive separation and catalytic degradation, was designed for dye removal, realizing an excellent dye rejection with easy and economic membrane regeneration through simply soaking the membrane in a limited volume of dilute oxidant solution. This approach is feasible and versatile owing to the flexible selection of distinct POMs and design of catalytic degradation routes as required. As a result, the current research provides insight into a new methodology of the membrane technique in dye removal applications. [ABSTRACT FROM AUTHOR]

A novel molecularly imprinted polymer (MIP)-coated magnetic TiO 2 nanocomposite was prepared, using methyl orange (MO) as the dummy template and pyrrole as functional monomer, for degradation of Congo red (CR). The nanocomposite was characterized by Fourier transform infrared spectroscopy, thermo-gravimetric analysis, X-ray diffraction, transmission electron microscopy, and vibrating sample magnetometer. The imprinting efficiency of the imprinted nanoparticles was investigated by static binding test, and their degradation ability toward CR was also studied. Moreover, the effects of pH, temperature, dissolved oxygen and oscillation rate on degradation rate of CR were investigated. Results showed that the imprinted nanocomposite had higher adsorption ability for MO compared with the non-imprinted one. Moreover, it could degrade CR rapidly in dark at room temperature and atmospheric pressure and could be recycled easily by a magnet with a good reusability. A degradation mechanism was proposed according to LC–MS analysis of degradation products of CR. The new imprinted nanoparticles showed high catalytic activity at ambient conditions without light illumination and additional chemicals, and therefore, it can be potentially applied to the rapid, “green” and low-cost degradation of CR in industrial printing and dyeing wastewater. [ABSTRACT FROM AUTHOR]

Although sulfate radical-based advanced oxidation processes (SR-AOPs) have shown great potential for the efficient degradation of various organic contaminants, there is few research on the removal of organophosphorus pesticides (OPPs) through SR-AOPs. In this work, Co-doped Fe 3 O 4 magnetic particles encapsulated by zirconium-based metal-organic frameworks (Co-Fe 3 O 4 @UiO-66) were prepared and employed to activate peroxymonosulfate (PMS) for the elimination of fenitrothion (FNT) and the simultaneous in-situ adsorption of produced phosphate. The catalyst exhibited efficient catalytic performance, achieving above 90.0% removal of FNT (10 mg/L) in the presence of PMS (1 mM) within 60 min. Moreover, the produced phosphate during the degradation process was also completely adsorbed onto the catalyst. Both sulfate and hydroxyl radicals were responsible for the degradation of FNT. The degradation products of FNT in the system were identified and the possible pathways were proposed. This study represents a promising and adoptable strategy to develop other versatile composite nanomaterials in a green manner hence broadening its environmental application range, as it can not only remove OPPs by catalytic oxidation but also immobilize degraded phosphorus by adsorption. [Display omitted] • A magnetic core-shell Co-Fe 3 O 4 @UiO-66 was designed and synthesized. • Efficient degradation of FNT and in-situ adsorption of phosphate were achieved simultaneously. • Catalytic mechanism PMS activation and phosphate adsorption were proposed. • Main degradation products and pathways of FNT were identified. [ABSTRACT FROM AUTHOR]

The potential risk of various contaminants in water has recently attracted public attention. Biochars and modified biochars have been widely developed for environmental remediation. Metal and heteroatom co-doped biochar composites (MHBCs) quickly caught the interest of researchers with more active sites and higher affinity for contaminants compared to single-doped biochar by metal or heteroatoms. This study provides a comprehensive review of MHBCs in wastewater decontamination. Firstly, the main fabrication methods of MHBCs were external doping and internal doping, with external doping being the most common. Secondly, the applications of MHBCs as adsorbents and catalysts in water treatment were introduced emphatically, which mainly included the removal of metals, antibiotics, dyes, pesticides, phenols, and other organic contaminants. Thirdly, the removal mechanisms of contaminants by MHBCs were deeply discussed in adsorption, oxidation and reduction, and degradation. Furthermore, the influencing factors for the removal of contaminants by MHBCs were also summarized, including the physicochemical properties of MHBCs, and environmental variables of pH and co-existing substance. Finally, futural challenges of MHBCs are proposed in the leaching toxicity of metal from MHBCs, the choice of heteroatoms on the fabrication for MHBCs, and the application in the composite system and soil remediation. [Display omitted] • Fabrication methods and characteristics of MHBCs are reviewed. • Application of MHBCs in water treatment are explicated emphatically. • Removal mechanism of contaminants by MHBCs are elaborated systematically. • Influencing factors for the removal of contaminants by MHBCs are discussed. • Future prospect for the fabrication and further application of MHBCs are proposed. [ABSTRACT FROM AUTHOR]

The abuse of cephalosporins poses a serious threat to human health and the ecological environment. In this work, cephalosporinase (AmpC enzyme) and Prussian blue (PB) crystals were encapsulated into ZIF-8 metal-organic frameworks (MOFs), and a photothermal AmpC/PB@ZIF-8 MOFs (APZ) nanocatalyst was prepared for the catalytic degradation of cephalosporin. The temperature of the APZ catalytic degradation system can be regulated by irradiation with near infrared light due to the photothermal effect of PB, and then, the activity of the APZ biocatalyst is significantly enhanced. Thereby, the degradation efficiency of cefuroxime can reach to 96%, and the degradation kinetic rate of cefuroxime augmented 4.5-fold comparing with that catalyzed by free enzyme. Moreover, encapsulation of the enzyme and PB can increase the affinity and charge transfer efficiency between APZ and substrate molecules, which can also improve the degradation efficiency of cephalosporins. Catalytic degradation pathways for three generations of cephalosporins were proposed based on their degradation products. The dual-enhancer biocatalyst based on the photothermal effect and immobilization of the PB and enzyme can significantly enhance the activity and stability of the enzyme, and it can also be recycled. Therefore, the biocatalyst has potential applications for the effective degradation of cephalosporins in the environment. [Display omitted] • Dual-enhancer biocatalyst was developed by one-pot in situ co-precipitation strategy. • Activity of biocatalyst can be enhanced by irradiation with near infrared light. • Catalytic degradation efficiency of cephalosporin was significantly improved. • The biocatalyst has high stability under harsh conditions and can be recycled. • Degradation pathways for three generations of cephalosporin have been proposed. [ABSTRACT FROM AUTHOR]

Highlights: [•] A novel dual-tank photoelectrochemical catalytic reactor was designed. [•] Malachite green degraded in bipolar double-effect mode. [•] Salt bridge replaced by a cation exchange membrane in the reactor. [•] Degradation pathways of malachite green in the cathode and anode tanks were similar. [Copyright &y& Elsevier]

Abstract: A comparative study of thermal and catalytic degradation of polyethylene wastes has been carried out with the aim of obtaining chemical compounds with potential use in the chemical industry and the energy production. Polyethylene wastes were obtained from polyethylene bags used in supermarkets. Catalysts utilized in the study were silica gel, 5A molecular sieve and activated carbon. The pyrolysis was performed in a batch reactor at 450, 500 and 700°C during 2h for each catalyst. The ratio catalyst/PE was 10% w/w and the solid and gaseous products were analyzed by gas chromatography and mass spectrometry. The optimum operation temperature and the influence of the three catalysts are discussed with regards to the products formed. The best temperature for degradation with silica gel and activated carbon as catalysts was 450°C and with 5A molecular sieve was 700°C. Degradation products of PE (solid fraction and gas fraction) are depending on temperature and catalyst used. External surface and structure of catalysts were visualized by Scanning Electron Microscopy (SEM) and the contribution on product distribution is commented. All products from different degradations could be used as feed stocks in chemical industry or in energy production based on the value of heat of combustion for solid fraction (45000J/g), similar to the heat of combustion of commercial fuels. [Copyright &y& Elsevier]

In the last decade, more and more refractory organic contaminants with severe health risks have been detected in the aquatic ecosystem. Sulfate radical (SO 4 · −)-based advanced oxidation process (SR-AOP) is recognized as an efficient approach for the removal of organic contaminants. Biochar (BC) and its composites (BCs) have been applied into SR-AOP for the double advantages of adsorption and catalytic ability. This paper gives systematic emphasis to the development and progress of biochar and its composites as catalyst in persulfate-advanced oxidation process. Synthetic techniques including the directed pyrolysis of mixed materials and post-immersed method are discussed. The physicochemical properties of biochar (such as surface area, surface functional groups, defect structure and persistent free radicals, etc.) that affect persulfate activation are provided. Then, emphasis is placed on the crucial role of biochar in affecting the catalytic property of BCs including stabilizing nanoparticles, expanding the surface area, increasing active sites and regulating electron transfer reactions. Integrating mechanistic insights and different biochar-based catalysts highlight the understanding of persulfate activation and catalytic degradation. Possible challenges are finally proposed in the fundamental research and practically scaled-up application. ga1 • Biochar and its composites exhibit considerable potential in PS activation. • Biochar applied as a support can stabilize and disperse the nanoparticles. • Biochar can increase the surface area and active sites. • Biochar is capable of promoting electron transfer or shuttling electrons. [ABSTRACT FROM AUTHOR]

• Various indicators for biochar-based catalytic performance evaluation were reviewed. • The formation of intermediates and by-products affects the catalyst sustainability. • The impact assessment of the treated samples was thoroughly discussed. • Five ubiquitously detected PPCPs were selected and evaluated as a case study. Considerable efforts have been made to develop effective and sustainable catalysts, e.g., carbon-/biochar-based catalyst, for the decontamination of organic pollutants in water/wastewater. Most of the published studies evaluated the catalytic performance mainly upon degradation efficiency of parent compounds; however, comprehensive and field-relevant performance assessment is still in need. This review critically analysed the performance indicators for carbon-/biochar-based catalytic degradation from the perspectives of: (1) degradation of parent compounds, i.e. , concentrations, kinetics, reactive oxidative species (ROS) analysis, and residual oxidant concentration; (2) formation of intermediates and by-products, i.e. , intermediates analysis, evolution of inorganic ions, and total organic carbon (TOC); and (3) impact assessment of treated samples, i.e. , toxicity evolution, disinfection effect, and biodegradability test. Five most frequently detected pharmaceuticals and personal care products (PPCPs) (sulfamethoxazole, carbamazepine, ibuprofen, diclofenac, and acetaminophen) were selected as a case study to articulate the performance indicators for a holistic evaluation of carbon-/biochar-based catalytic degradation. This review also encourages the development of alternative performance indicators to facilitate the rational design of catalysts in future studies. [ABSTRACT FROM AUTHOR]

• Elbaite was used for the first time to activate PMS. • Elbaite can activate PMS in a wide pH range of 2.9–10.7. • PMS was activated easily by elbaite with low activation energy of 18.6 kJ/mol. • SO 4 − and OH were produced successfully by activating PMS with elbaite. • MB, DOX, and BPA in wastewater can be efficiently removed by PMS/elbaite. In this work, the abundant, low−cost, innocuous, and chemically stable elbaite (a type of tourmaline) was employed to catalyze peroxymonosulfate (PMS) for wastewater purification by using methylene blue (MB) as one of the target pollutants. The results revealed that PMS could be catalyzed by elbaite within broad pH range (i.e., 2.9–10.7) and with low activation energy (i.e., 18.6 kJ/mol). Complete MB degradation was obtained within 15 min under the optimized conditions: [elbaite] 0 = 1.00 g/L, [PMS] 0 = 0.50 g/L, initial solution pH = 2.9. MB degradation (%) sustained 99.9 % after five successive catalytic reactions, indicating good durability and long−term stability. In addition, the complete degradation of doxycycline hydrochloride (DOX) and bisphenol A (BPA) further confirmed the degradation activity of the PMS/elbaite system. PMS interacted with elbaite via replacing the surface−bonded and structural OH groups of elbaite with its OH groups to bond with Y Li Y Al Y R and Y Li Z Al Z R cations (R = Al, Li, Fe, Mg, Mn, Cr, V), which offered channels for electron transfer from negatively charged elbaite to PMS, leading to the activation of PMS. Thus, elbaite is found to be promising for catalyzing PMS to treat organic wastewater. [ABSTRACT FROM AUTHOR]

• Photothermal graphene/MOF fabrics are synthesized for degrading simulants of CWAs. • The flexible fabric exhibits ultrafast photothermal catalytic degradation of DMNP. • Photothermal conversion of graphene accelerates catalytic reaction kinetics of MOFs. Lightweight and wearable fabrics with rapid self-detoxification functions are highly desired to resist chemical warfare agents (CWAs). Metal organic frameworks (MOFs) with high specific surface area and customizability are singularly attractive because of their ability to effectively capture and catalytically degrade CWAs. Herein, photothermal graphene-based nanocomposite fabrics are designed by wet-spinning and chemical reduction of graphene oxide fibers followed by in situ growth of UiO-66-NH 2. The flexible graphene fabrics decorated with UiO-66-NH 2 nanoparticles exhibit an ultrafast photothermal catalytic decontamination of dimethyl 4-nitrophenyl phosphate (DMNP), a typical simulant of CWAs. The half-life of the degradation reaction decreases from 3.4 to 1.6 min under simulated solar light irradiation, a significant gain over the values reported in the literature. Furthermore, DMNP can be degraded in 20 min by the graphene/UiO-66-NH 2 fabric, and even after 5 cycles the degradation efficiency still retains more than 92 %. More importantly, the photothermal conversion of graphene and its instantaneous heat transfer to the UiO-66-NH 2 catalyst effectively accelerate the catalytic reaction kinetics, achieving the fast detoxification of DMNP. The combination of catalytic degradation of MOFs with photothermal conversion effect of graphene makes the lightweight and flexible fabrics promising for protection against CWAs and other pollutants. [ABSTRACT FROM AUTHOR]

Carbon and defects co-modified carbon nitride (C x CN) was synthesized by a novel and facile method, shows porous structure, a lower bandgap and longer life of photogenerated electron-hole pairs for more fully use of solar-energy, and thus its photocatalytic degradation activity is about 22 times higher than that of pristine g-C 3 N 4. • Carbon and defects co-modified g-C 3 N 4 (C x CN) was synthesized with a facile method. • Carbon and defects tune the band structure to promote utilization of solar energy. • C x CN structure is established by DFT calculation to explain related mechanism. • C x CN shows efficiently photocatalytic degradation of BPA under visible light. Graphite carbon nitride (g -C 3 N 4 , CN) is considered as a promising semiconductor for environmental catalysis. However, pure CN can not meet the requirements for actual applications due to its high recombination rate of photogenerated electron-hole pairs and a relatively large band gap preventing full utilization of solar energy. In this work, we report synthesis of a novel carbon and defects co-modified g -C 3 N 4 (C x CN) by calcination of melamine activated by oxalic. This new catalyst C x CN has porous structure with much higher surface areas compared with pristine CN. UV–vis analysis and DFT calculations show that C x CN has a lower bandgap for enhancing visible light adsorption compared with CN. Photoluminescence (PL) and photoelectrochemical analyses show that C x CN has a low recombination rate of photogenerated electron-hole pairs, which improves the utilization of solar energy. As a result, C x CN samples show high efficiency for the degradation of bisphenol A (BPA) under visible light irradiation, where the best catalyst of C x CN (C 1.0 CN) samples shows about 22 times higher photocatalytic degradation rate than that of CN. Moreover, C 1.0 CN shows high mineralization rate and can degrade BPA into CO 2 and H 2 O by the generated active species, like superoxide radicals (O 2 −) and holes (h+). [ABSTRACT FROM AUTHOR]