Cellulose derived carbon nanofiber: A promising biochar support to enhance the catalytic performance of CoFe2O4 in activating peroxymonosulfate for recycled dimethyl phthalate degradation

Peroxymonosulfate activation by nanocomposites towards the removal of sulfamethoxazole: Performance and mechanism

Heterogeneous activation of peroxomonosulfate (PMS) has been extensively studied for the degradation of antibiotics. The cobalt ferrite spinel exhibits good activity in the PMS activation, but suffers from the disadvantage of low PMS utilization efficiency. Herein, the nanocomposites including FeS, CoS2, CoFe2O4 and Fe2O3 were synthesized by hydrothermal method and used for the first time to activate PMS for the removal of sulfamethoxazole (SMX). The nanocomposites showed superior catalytic activity in which the SMX could be completely removed at 40 min, 0.1 g L-1 nanocomposites and 0.4 mM PMS with the first order kinetic constant of 0.2739 min-1. The PMS utilization efficiency was increased by 29.4% compared to CoFe2O4. Both radicals and non-radicals contributed to the SMX degradation in which high-valent metal oxo dominated. The mechanism analysis indicated that sulfur modification, on one hand, enhanced the adsorption of nanocomposites for PMS, and promoted the redox cycles of Fe2+/Fe3+ and Co2+/Co3+ on the other hand. This study provides new way to enhance the catalytic activity and PMS utilization efficiency of spinel cobalt ferrite.

Interfacial coupling effect promotes selective electrocatalytic oxidation of 5-hydroxymethylfurfural into the value-added products under neutral conditions

Owing to the sluggish reaction kinetics, it is a promising yet challenging task to achieve the adequate electricity-driven catalytic oxidation of biomass-derived 5-hydroxymethylfurfural (HMF) in neutral conditions. Herein, we have prepared an elelctrocatalyst with interfacial coupling effect through in-situ growth of Cu phthalocyanine (CuPc) on Co3O4 spinel (Co3O4/CuPc), which constructs an effective electrocatalytic system of HMF oxidation with overall oxidation value-added products yield and total Faraday efficiency up to 80% and 70%, respectively. The interfacial coupling effect between CuPc and Co3O4 spinel improve catalytic activity by effectively boosting the interfacial charge transfer and reducing the formation energy of key *C6H3O4 in the catalytic pathway according to the in situ Raman spectroscopy and DFT simulation. This work illustrates the significance of interfacial coupling effect for developing highly efficient electrocatalysts applied for neutral system of biomass oxidation.

Preparation of agar functionalized graphene oxide-immobilized copper ferrite aerogel for dye degradation via dark-Fenton oxidative process

Dye and textile industries are one of the main causes of water pollution and put the environment and health of society at risk. Developing new materials to decontaminate industrial waste effluents containing dyes as pollutants is challenging due to numerous issues, including tailoring recyclable and biodegradable agents. This study focuses on applying an advanced oxidation process, electro-Fenton for the treatment of dye-containing wastewater using agar-functionalized graphene oxide-immobilized copper ferrite aerogel. The objective is therefore to determine the optimal conditions for the degradation of model pollutants methylene blue (MB). MB was oxidized and degraded through the dark-Fenton process using Agar@GO-CuFe2O4 as a new biobased catalyst. The effect of the operating parameters was then evaluated to determine the optimal conditions. The degradation process was screened for different initial concentrations of dye solution between 10 and 150 mg/l, a volume range of H2O2 between 0.5 and 2.5 ml, and different pH from 2 to 7. The results show that 99.89 % of the MB with the initial concentration of 150 ppm was degraded by 20 mg of the catalyst and 2 ml of H2O2 (30 % W/W) at 40 °C and pH = 6. Pseudo-second-order kinetics satisfactorily describes the experimental data. SYNOPSIS: The prepared catalyst can be applied to oxidize industrial effluents before they are released into the environment.

Influence mechanisms of different stalks on iron species type of magnetic biochar prepared from Fe2O3

The current selection of biomass feedstock for magnetic biochar (MBC) catalysts is highly blind. Consequently, this study delves into understanding how the types of biomass influence the iron species present in MBC catalysts. The process involved the creation of MBC through simulated impregnation-pyrolysis, utilizing six types of stalks and Fe2O3. The type of iron species significantly impacted magnetic properties and likely influenced catalytic properties of MBC. MBC's iron species type was shaped by the reduction effects of the diverse stalks on Fe2O3. During the pyrolysis, discrepancies were observed in the release of reducing gases and direct reduction for the different stalks. These differences in reduction behavior directly accounted for the distinct reduction effects. To delve deeper, the reduction behavior and effect of the main components of the stalk (hemicellulose, cellulose, and lignin) on Fe2O3 were analyzed, highlighting lignin as the most effective. Nonetheless, the absolute values of Pearson's r between lignin content in the stalk and reduction behavior/effect ranged only from 0.078 to 0.421. In contrast, the values for K, Ca, and Si content in the stalks and their influence on reduction behavior and MBC's reduction/metallization degree ranged from 0.410 to 0.910. The catalytic impacts of K and Ca were confirmed through their incorporation into cotton and reed stalks. The disparities in K, Ca, and Si content among the six stalks appeared to be the primary driver behind the diverse iron species in MBC. This work provides a scientific basis for the rational selection of biomass feedstock for MBC catalysts.

Catalytic Properties of Biochar as Support Material Potential for Direct Methanol Fuel Cell: A Review

With the evolution and emergence of compounding environmental problems and issues, renewable energy promises to be a sustainable future technology. One technology considered is the fuel cell, which thrives on the primary function of electrocatalytic activities. Thus this review article envisages and presents a comprehensive summary of the applications of activated carbonaceous material as supports for electrocatalysts in fuel cells. The different techniques utilized to produce these carbon materials are discussed in detail. The overview architecture and the principle of the operation of fuel cells are also addressed. Additionally, electrocatalysts and the importance of support materials, their characteristics, and the role they play in the performance of the electrocatalyst will be reviewed. Unfortunately, the carbon-support-based electrocatalyst suffers long-term instability due to corrosion. Previously, carbon black has been used as a carbon support in various fuel cells. In recent years, there has been progress in the incorporation of nanostructured carbon supports in electrocatalysts in various fuel cells; however, there is still a great deal of distance to cover for nanostructured carbon-supported electrocatalysts in fuel cells to realize full commercialization and large-scale industrial purposes due to shortcomings in electrocatalysts, which are low-cost and highly efficient. This review therefore discusses the progress of incorporation of biochar extracted from sugar cane bagasse as carbon support in electrocatalysts for direct methanol fuel cells with the intention to provide insight into the quest of producing highly efficient and low cost fuel cells.

Synergetic effect of photocatalytic oxidation plus catalytic oxidation on the performance of coconut shell fiber biochar decorated α-MnO2 under visible light towards BPA degradation

Photocatalytic technology is regarded as a promising approach for fast degradation of refractory organic pollutant in water. However, the performance of the photocatalyst can be restricted by the variation of water matrix conditions. Herein, coconut shell fiber was pyrolyzed to biochar (CSB800) and incorporated with α-MnO2 to degrade bisphenol A (BPA) in water under visible light irradiation. The prepared α-MnO2/CSB800 composites demonstrated high efficacy in degrading BPA. Specifically, 0.01 mM of BPA could be completely degraded by 0.1 g/L of MnO2/CSB800 within 45 min. It was found that the incident light could effectively trigger the separation of electron and hole in α-MnO2. The electron and hole were afterwards converted to hydroxyl radical (●OH), superoxide radical (●O2-) and non-radical singlet oxygen (1O2), which subsequently initiated the photocatalytic degradation of BPA. Additionally, α-MnO2/CSB800 could simultaneously participate the oxidative degradation pathway of BPA with its high oxidation-reduction potential. The introduction of CSB800 led to higher BPA degradation efficiency since CSB800 could accelerate the charge carrier transferring rate during BPA degradation process via either pathway. The co-existence of both photocatalytic and oxidative degradation synergy enables α-MnO2/CSB800/visible light system with high catalytic performance stability towards various water matrices. This study proposes an effective strategy to prepare easy-available photocatalysts with high and stable performance towards for addressing organic pollution issues in water.

Co-Mn-Fe spinel-carbon composite catalysts enhanced persulfate activation for degradation of neonicotinoid insecticides: (Non) radical path identification, degradation pathway and toxicity analysis

The extensive utilization of neonicotinoid insecticides (NNIs) in agricultural practices ultimately poses a significant threat to both the environment and human health. This work focuses on the efficient degradation and detoxification of the representative NNI, thiamethoxam (THX), and explores the underlying mechanism using a Co-Fe-Mn mixed spinel doped carbon composite catalyst activated persulfate. The findings demonstrate that the composite effectively degrades THX, achieving a degradation rate of 95% in 30 mins, while requiring only a fraction (one-sixteenth) of the oxidant dosage compared to pure carbon. The study aimed to examine the negative impact of reactive halogens on reactive oxygen species within a saline environment. The degradation byproducts were linked to the presence of two common electron-withdrawing groups, namely halogens and nitro in the THX molecule. It was hypothesized that the degradation process was primarily influenced by C-N bond breaking and hydroxylation occurring between the diazine oxide and 2-chlorothiazole rings. Consequently, dehalogenation and carbonylation processes facilitated the elimination of halogenated components and pharmacophores from the THX, leading to detoxification. In addition to the identified free radical pathway including SO4•-, •OH and O2•- contributed to THX degradation, the participation of non-radical pathways (1O2 and electron transfer) were also confirmed. The efficacy of detoxification was further validated through toxicity assessment, employing quantitative conformation relationship prediction and microbial culture utilizing Bacillus subtilis.

Advanced oxidation processes for phthalate esters removal in aqueous solution: a systematic review

This study addresses a systematic review of the scientific literature to evaluate the most common advanced oxidation processes (AOP) for the removal of phthalate esters (PE) in aqueous matrices. Six AOP were reviewed for PE degradation such as processes based on photolysis, Fenton, ozonation and sulfate radicals ( SO 4 • - ), combined AOP and other processes. The PE degradation efficiencies by AOP processes ranged from 40.3 to 100%. In the reviewed literature, an initial PE concentration within 0.04-250 mg/L was applied. The H₂O₂ concentrations used in the UV/H₂O₂ process and O₃ concentrations in ozonation-based processes ranged between 0.85-1,360.6 mg/L and 2-4,971 mg/L, respectively. Based on the reported results, the PE oxidation data fit well to the pseudo-first order kinetic model. A review of the studies revealed that many oxidant species are produced in the AOP, including hydroxyl radicals (^•OH), SO 4 • - , superoxide radical anions ( O 2 - • ), hydroperoxyl radicals (HO₂ ^•), hydrogen peroxide (H₂O₂), and singlet oxygen (O₂). Among these oxidants, ^•OH play a key role in the degradation of PE. However, SO 4 • - are more effective and efficient than ^•OH since SO 4 • - has a higher oxidation power (E = 2.5-3.1 V) compared to ^•OH radicals (E = 1.8-2.7 V). In different AOP processes, the aromatic rings of PE are destroyed by ^•OH and produce intermediates such as phthalic acid (C₆H₄(CO₂H)₂), benzoic acid ethyl ester (C₉H₁₀O₂), 2, 5-dihydroxybenzoic acid (C₇H₆O₄), formic acid (CH₂O₂), acetic acid (CH₃COOH), and oxalic acid (C₂H₂O₄), among some others. Until now, limited data have been reported on PE toxicity assessment. The reviewed literature has shown that AOP can be used effectively to degrade PE from aqueous matrices. However, this systematic study suggests focusing more on the evaluation of the toxicity of the effluent resulting from AOP for the decomposition of PE in future studies.

Spinel cobalt ferrite-based porous activated carbon in conjunction with UV light irradiation for boosting peroxymonosulfate oxidation of bisphenol A

Developing heterogeneous catalysts with high performance for peroxymonosulfate (PMS) activation to decontaminate organic pollutants from wastewater is of prominent importance. In this study, spinel cobalt ferrite (CoFe₂O₄) materials were coated on the surface of powdered activated carbon (CoFe₂O₄@PAC) via the facile co-precipitation method. The high specific surface area of PAC was beneficial for the adsorption of both bisphenol A (BP-A) and PMS molecules. The CoFe₂O₄@PAC-mediated PMS activation process under UV light could effectively eliminate 99.4% of the BP-A within 60 min of reaction. A significant synergy effect was attained between CoFe₂O₄ and PAC towards PMS activation and subsequent elimination of BP-A. Comparative tests demonstrated that the heterogeneous CoFe₂O₄@PAC catalyst had a better degradation performance in comparison with its components and homogeneous catalysts (Fe, Co, and, Fe + Co ions). The formed by-products and intermediates during BP-A decontamination were evaluated using LC/MS analysis, and then a possible degradation pathway was proposed. Moreover, the prepared catalyst exhibited excellent performance in recyclability with slight leaching amounts of Co and Fe ions. A TOC conversion of 38% was obtained after five consecutive reaction cycles. It can be concluded that the PMS photo-activation process via the CoFe₂O₄@PAC catalyst can be utilized as an effective and promising method for the degradation of organic contaminants from polluted-water resources.

Peroxymonosulfate and peroxydisulfate activation by fish scales biochar for antibiotics removal: Synergism of N, P-codoped biochar

Social development is accompanied by technological progress, which commonly leads to the expansion of pollution As an essential resource of modern medical treatment, antibiotics have become a hot topic in the aspect of environmental pollution. In this study, we first used fish scales to synthesize N, P-codoped biochar catalyst (FS-BC) as peroxymonosulfate (PMS) and peroxydisulfate (PDS) activator to degrade tetracycline hydrochloride (TC). At the same time, peanut shell biochar (PS-BC) and coffee ground biochar (CG-BC) were prepared as reference materials. Among them, FS-BC exhibited the best catalytic performance due to the excellent defect structure (I_D/I_G = 1.225) and the synergism of N, P heteroatoms. PS-BC, FS-BC and CG-BC achieved degradation efficiencies of 86.26%, 99.71% and 84.41% for TC during PMS activation and 56.79%, 93.99% and 49.12% during PDS, respectively. In both FS-BC/PMS and FS-BC/PDS systems, non-free radical pathways involved singlet oxygen (¹O₂), surface-bound radicals mechanism and direct electron transfer mechanism. Structural defects, graphitic N and pyridinic N, P-C groups and positively charged sp² hybridized C adjacent to graphitic N were all critical active sites. FS-BC has the potential for practical applications and development because of its robust adaptation to pH and anions and stable re-usability. This study not only provides a reference for biochar selection, but also suggests a superior strategy for TC degradation in the environment.

Phthalate esters: occurrence, toxicity, bioremediation, and advanced oxidation processes

Phthalic acid esters are emerging pollutants, commonly used as plasticizers that are categorized as hazardous endocrine-disrupting chemicals (EDCs). A rise in anthropogenic activities leads to an increase in phthalate concentration in the environment which leads to various adverse environmental effects and health issues in humans and other aquatic organisms. This paper gives an overview of the research related to phthalate ester contamination and degradation methods by conducting a bibliometric analysis with VOS Viewer. Ecotoxicity analysis requires an understanding of the current status of phthalate pollution, health impacts, exposure routes, and their sources. This review covers five toxic phthalates, occurrences in the aquatic environment, toxicity studies, biodegradation studies, and degradation pathways. It highlights the various advanced oxidation processes like photocatalysis, Fenton processes, ozonation, sonolysis, and modified AOPs used for phthalate removal from the environment.

Activation of peroxymonosulfate by palygorskite supported Co-Fe for water treatment

In the present work, palygorskite (PAL) supported Co-Fe oxides (CoFe@PAL) were prepared and used as a peroxymonosulfate (PMS) activator for removal of rhodamine B (RhB) in water. The results showed that CoFe@PAL prepared at impregnation solution of 50 g L^-1 and calcination temperature of 500 °C showed the best catalytic performance. The removal efficiency of RhB (10 mg L^-1) by PMS (0.1 mmol L^-1) activated with CoFe@PAL (1 g L^-1) was above 98% within 60 min. The effects of various environmental factors including initial pH, humic acid (HA) and inorganic anions on the removal effect were simultaneously investigated. The radical quenching experiments and EPR characterization revealed that ˙OH, SO₄˙^-, O₂˙^- and ¹O₂ radicals existed in the CoFe@PAL/PMS system simultaneously. The intermediates during RhB degradation were analyzed by LC-MS and possible degradation pathways of RhB were proposed. Moreover, CoFe@PAL exhibited superior stability and reusability.

Degradation of organic pollutants from water by biochar-assisted advanced oxidation processes: Mechanisms and applications

Biochar has shown large potential in environmental remediation because of its low cost, large specific surface area, porosity, and high conductivity. Biochar-assisted advanced oxidation processes (BC-AOPs) have recently attracted increasing attention to the remediation of organic pollutants from water. However, the effects of biochar properties on catalytic performance need to be further explored. There are still controversial and knowledge gaps in the reaction mechanisms of BC-AOPs, and regeneration methods of biochar catalysts are lacking. Therefore, it is necessary to systematically review the latest research progress of BC-AOPs in the treatment of organic pollutants in water. In this review, first of all, the effects of biochar properties on catalytic activity are summarized. The biochar properties can be optimized by changing the feedstocks, preparation conditions, and modification methods. Secondly, the catalytic active sites and degradation mechanisms are explored in different BC-AOPs. Different influencing factors on the degradation process are analyzed. Then, the applications of BC-AOPs in environmental remediation and regeneration methods of different biochar catalysts are summarized. Finally, the development prospects and challenges of biochar catalysts in environmental remediation are put forward, and some suggestions for future development are proposed.

Synthesis of biochar-CoFe2O4 nanocomposite for adsorption of methylparaben from wastewater under full factorial experimental design

The presence of endocrine-disrupting chemicals in municipal wastewater has emerged as a threat to human health and the environment. Therefore, this study aimed to develop biochar-cobalt ferrite (BCF) nanocomposite for the removal of methylparaben from water under the full factorial experimental design of 4 factors with 3 levels (3⁴). The biochar-CoFe₂O₄ nanocomposite was developed by co-precipitation method from cobalt ferrite and biochar of Eucalyptus tree bark. Adsorbent surface morphology and functional and elemental composition were carried out by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and energy-dispersive X-ray spectroscopy (EDS) techniques which showed the presence of cracks with a rough surface, reasonable surface chemical composition, and many chemical functional groups, respectively. The experimental and predicted adsorption efficiencies ranged from 25.3 to 85.6% and 21.8 to 80.3%, respectively. The maximum adsorption performance (85.6%) reduced the methylparaben concentration from 27.5 to 4.0 mg/L at the optimum condition of adsorbent dose of 55 mg/100 mL, pH 6, contact time 90 min, and the initial methylparaben concentration of 27.5 mg/L. However, the adsorbent dose was the most influential main factor whereas the least influential was the interaction between solution pH and contact time under the regression model. The model also showed that 69% methylparaben removal was described by the regression model. The experimental data best fitted with the Freundlich model indicate multilayer adsorption which is the implication of physisorption. The sorption mechanism is attributed to Vander Waals forces, H-bonding, and dipole interaction. This BCF nanocomposite adsorbent appears to be promising for the removal of methylparaben from wastewater, but a further optimization process is essential to boost the treatment performance.

N Doped Activated Biochar from Pyrolyzing Wood Powder for Prompt BPA Removal via Peroxymonosulfate Activation

In the present study, nitrogen doped biochar (N-PPB) and nitrogen doped activated biochar (AN-PPB) were prepared and used for removing bisphenol A (BPA) in water through activating peroxymonosulfate. It was found from the results that N-PPB exhibited superior catalytic performance over pristine biochar since nitrogen could brought about abundant active sites to the biochar structure. The non-radical singlet oxygen (1O2) was determined to be the dominant active species responsible for BPA degradation. Having non-radical pathway in the N-PPB/PMS system, the BPA degradation was barely influenced by many external environmental factors including solution pH value, temperature, foreign organic, and inorganic matters. Furthermore, AN-PPB had richer porosity than N-PPB, which showed even faster BPA removal efficiency than N-PPB through an adsorptive/catalytic synergy. The finding of this study introduces a novel way of designing hieratical structured biochar catalysts for effective organic pollutant removal in water.

Spinel ferrites materials for sulfate radical-based advanced oxidation process: A review

In the past decade, the sulfate radical-based advanced oxidation processes (SR-AOPs) have been increasingly investigated because of their excellent performance and ubiquity in the degradation of emerging contaminants. Generally, sulfate radicals can be generated by activating peroxodisulfate (PDS) or peroxymonosulfate (PMS). To date, spinel ferrites (SF) materials have been greatly favored by researchers in activating PMS/PDS for their capability and unique superiorities. This article reviewed the recent advances in various pure SF, modified SF, and SF composites for PDS/PMS activation. In addition, synthesis methods, mechanisms, and potential applications of SF-based SR-AOPs were also examined and discussed in detail. Finally, we present future research directions and challenges for the application of SF materials in SR-AOPs.

ZIF-67(Co)-Loaded Filter Paper for In Situ Catalytic Degradation of Bisphenol A in Water

Herein, we loaded cobalt-based zeolite imidazolate frameworks, ZIF-67 (Co), onto commercial filter paper to prepare catalytic filter paper (ZFP) for the in situ degradation of bisphenol A (BPA) in water by activating peroxymonosulfate. The results showed that ZIF-67 (Co) was densely and uniformly distributed on the surface of the filter paper. The prepared ZFP could effectively degrade BPA in situ through a gravity-driven filtration process. Specifically, when the flow rate of the BPA solution passing through ZFP was lower than 10 mL/min, 0.02 mM of BPA could be completely degraded by ZFP. Furthermore, ZFP showed promising water matrix adaptability, which could provide promising BPA degradation efficiency in a wide pH range or in the existence of multiple anions. The scavenging tests demonstrated that both sulfate radical and hydroxyl radical were generated for BPA degradation, in which hydroxyl radical was the dominant active species. The ZFP also exhibited promising long-time use stability with a high mineralization rate. This study provides a novel method to prepare high-efficient catalyst paper for the in situ organic pollutant removal in water media via a prompt filtration process.

Polymeric biomolecules based nanomaterials: Production strategies and pollutant mitigation as an emerging tool for environmental application

The ever-exploding global population coupled with its anthropogenic impact has imparted unparalleled detrimental effects on the environment and mitigating them has emerged as the prime challenge and focus of the current century. The niche of nanotechnology empowered by composites of biopolymers in the handling of xenobiotics and environmental clean-up has an unlimited scope. The appositeness of biopolymer-nanoparticles (Bp-NPs) for environmental contaminant mitigation has received unique consideration due to its exclusive combination of physicochemical characteristics and other attributes. The current review furnishes exhaustive scrutiny of the current accomplishments in the development of Bp-NPs and biopolymer nanomaterials (Bp-NMs) from various polymeric biomolecules. Special attention was provided for polymeric biomolecules such as cellulose, lignin, starch, chitin, and chitosan, whereas limited consideration on gelatin, alginate, and gum for the development of Bp-NPs and Bp-NMs; together with coverage of literature. Promising applications of tailored biopolymer hybrids such as Bp-NPs and Bp-NMs on environmentally hazardous xenobiotics handling and pollution management are discussed as to their notable environmental applications.

Catalytic Degradation of Bisphenol A in Water by Poplar Wood Powder Waste Derived Biochar via Peroxymonosulfate Activation

A series of biochar materials was prepared through pyrolyzing poplar wood powder waste under different pyrolyzing temperatures, which were afterwards characterized in detail. Then, the poplar powder biochar (PPB) was used to degrade bisphenol A (BPA) in water via activating peroxymonosulfate (PMS). The results indicate that the activation efficiency of the prepared PPB was correlated with its surface functional groups, which were regulated by its pyrolyzing temperature. Specifically, the biochar pyrolyzed at 600 °C (PPB-600) exhibited the optimal BPA removal activity, in which 0.5 g/L of PPB-600 could remove 0.02 mM of BPA within 120 min. From the results of scavenging tests, ESR analysis and probe pollutant degradation tests, it was inferred that the BPA was degraded by non-radical singlet oxygen in the PPB/PMS system. Since PPB consumed its surface oxygen functional groups and structural defects to activate PMS, the catalytic performance of PPB was gradually reduced after several cycles. This study can provide new insight for the design and preparation of metal-free biochar catalysts from waste wood precursor for the highly-efficient removal of refractory organic pollutants in water.

One-pot synthesis of a cellulose-supported CoFe2O4 catalyst for the efficient degradation of sulfamethoxazole

Cellulose-supported cobalt ferrite (CoFe₂O₄/RC) was synthesized via a facile one-pot hydrothermal method and demonstrated to be an efficient catalyst to activate peroxymonosulfate (PMS) for the degradation of sulfamethoxazole (SMX). The characterizations of CoFe₂O₄/RC catalysts revealed that an appropriate particle size of the cellulose support could promote the dispersion of CoFe₂O₄ nanoparticles and consequently promote the catalytic activity of the resulting CoFe₂O₄/RC catalysts. The degradation of SMX reached 97.6 % within 20 min at 30 °C with the CoFe₂O₄/RC/PMS system. The mechanism of SMX degradation over CoFe₂O₄/RC-activated PMS was studied via EPR, XPS, and quenching tests. The results suggested that ¹O₂ was the dominant reactive oxygen species and was accompanied by SO₄^-, OH, and O₂^- radicals for SMX degradation. The CoFe₂O₄/RC catalyst exhibited high stability and recyclability and maintained high catalytic activity after five experimental cycles.

The potential of biochar-photocatalytic nanocomposites for removal of organic micropollutants from wastewater

Biochar (BC)-photocatalyst nanocomposites have emerged as appealing water and wastewater treatment technology. Such nanocomposite materials benefit from the synergistic effect of adsorption and photocatalysis to attain improved removal of pollutants from water and wastewater. Under this review, three BC-based nanocomposite photocatalysts such as BC-TiO₂, BC-ZnO, and BC-spinel ferrites were considered. These nanocomposites acquire intrinsic properties to improve the practical limitations of the pristine BC and photocatalysts. The BC-based nanocomposites attained high photocatalytic activity, mechanical hardness, thermal stability, chemically non-reactive, magnetically permeable, reduced energy band gaps, improved reusability, and simplified recovery. Moreover, BC-based photocatalytic nanocomposites showed reduced recombination rates of the electron-hole pairs which are desirable for photocatalytic applications. However, the surface areas of the composites are usually smaller than that of the BC but higher than those of the pristine photocatalysts. Practically, the performances of the nanocomposites are much superior to those of the corresponding pristine components. This hybrid treatment technology is an emerging field and its industrial application is still at an early stage of the investigation. Therefore, exploring the full potential and practical applications of this technology is highly encouraging. Hence, this review focused on the critical evaluation of the most recent research on the synthesis, characterization, and photocatalytic treatment efficiency of the BC photocatalyst nanocomposites towards emerging pollutants in the aqueous medium. Moreover, the influence of various sources of BC feedstocks and their limitations on adsorption and photodegradation activities are discussed in detail. Finally, concluding remarks and future research directions are given to assist and shape the exploration of BC-based nanocomposite photocatalysts in water treatment.

Facile synthesis of CoFe2O4@BC activated peroxymonosulfate for p-nitrochlorobenzene degradation: Matrix effect and toxicity evaluation

p-Nitrochlorobenzene (p-NCB) is widely used in industry and poses a potential threat to the public health due to its persistence, carcinogenicity and mutagenicity. Herein, magnetic catalyst CoFe₂O₄@Biochar (CoFe₂O₄@BC) was synthesized by a facile sol-gel method, efficiently activating peroxymonosulfate (PMS) to degrade p-NCB. The synergistic effect of Fe and Co in well-dispersed CoFe₂O₄ and the electron transfer promote the production of reactive oxygen species (ROS) (OH, SO₄^- and O₂^-), efficiently removing p-NCB enriched by CoFe₂O₄@BC. Under optimum conditions, the CoFe₂O₄@BC/PMS system could remove 89% of p-NCB from water, and the degradation efficiency could reach 80% in soil. Toxic chlorinated intermediates appeared during the degradation process and thus efficient dechlorination process can lower the toxicity of the reaction solution, which was also proved by the oxygen uptake inhibition experiment as well as zebrafish toxicity experiments. Furthermore, p-NCB degradation efficiency could be inhibited by Cl^-, HCO₃^-, HPO₄^2- and humic acid (HA) through quenching effect or occupation of CoFe₂O₄@BC surface active sites while HPO₄^2- could also improve the efficiency by directly activating PMS. The CoFe₂O₄@BC/PMS system can be efficiently applied in the remediation of p-NCB pollution in water and soil.

Long-acting CoAl2O4 spinel catalyst developed on activated alumina pellets by facile synthesis to activate peroxymonosulfate: Controllable cobalt leaching and environmental adaptability

A novel composite catalyst prepared by fixing cobalt aluminate (CoAl₂O₄) spinel on formed alumina carrier by impregnation-calcination route is reported, which can be used to efficiently activate peroxymonosulfate (PMS) to degrade p-nitrophenol (PNP). The internal laws of phase composition and preparation conditions are explored in detail, and the results show that the introduction of additional aluminum ions in the preparation process changes the coordination environment and the electronic state of cobalt ions, which leads to the transformation of spinel/inverted spinel in the composition, and further affects the activity and stability of the catalyst. The selected CoAl-Aaps-600 catalyst has high CoAl₂O₄ content, showing good cycle performance and low cobalt leaching, and has great catalytic degradation performance at different temperatures and a wide pH range. Most notably, a fixed bed reactor packed with 20 g of CoAl-Aaps-600 exhibits excellent capacity to continuously treat 60 L of PNP solution with acceptable PNP removal ratio and low cobalt leaching content. Sulfate radical and singlet oxygen are identified as the main reactive oxygen species produced in CoAl-Aaps-600/PMS system, and the reaction mechanism is reasonably inferred. This work provides a potential application material and process for the treatment of continuous organic wastewater.

Facile fabrication of surface vulcanized Co-Fe spinel oxide nanoparticles toward efficient 4-nitrophenol destruction

Developing efficient modulation strategies to boost the degradation efficiencies of non-noble metal catalysts for toxic phenolic compounds involving peroxymonosulfate (PMS)-based oxidation processes is essential but remains an arduous challenge. This study reports the one-pot construction of in-situ surface vulcanized CoFe₂O₄ @carbon (S_x-CF@C) to boost the PMS activation for 4-nitrophenol (4-NP) destruction. The direct pyrolysis of an aerogel precursor consisted of cobalt nitrate, ferric nitrate, melamine, and thiourea enables the as-formed S_x-CF@C with hierarchical structure, rich oxygen vacancies, and electron/mass transfer, thereby considerably promoting PMS activation performance of S_x-CF@C toward 4-NP degradation. Specifically, the optimal S_0.2-CF@C can achieve a removal efficiency of 99% for 4-NP destruction (20 mg/L) through PMS activation. Meanwhile, the catalyst also has generality to degrade a variety of antibiotic and dye organic pollutants. The radical quenching and electron paramagnetic resonance tests reveal the radical and non-radical activation mechanism in the S_0.2-CF@C/PMS system. The degradation pathway for 4-NP destruction over the S_0.2-CF@C/PMS system is proposed. This study provides an efficient approach to modulate the PMS activation performance of ferrite spinel materials toward the degradation of acute phenolic compounds.

Insights into photocatalytic degradation of phthalate esters over MSnO3 perovskites (M = Mg, Ca): Experiments and density functional theory

In this study, the physicochemical and photocatalytic properties of two kinds of stannate perovskite oxides (MgSnO₃ and CaSnO₃) were investigated under simulated sunlight, where dimethyl phthalate (DMP) and diethyl phthalate (DEP) were selected as the probe pollutants. The results of photochemical characterization showed that MgSnO₃ perovskite exhibited better photocatalytic performance than CaSnO₃ perovskite. MgSnO₃ perovskite could effectively degrade 75% of DMP and 79% of DEP through pseudo-first-order reaction kinetics, which remained good in pH 3.0 to 9.0. Quenching experiments and electron paramagnetic resonance (EPR) characterization indicated that photogenerated holes (h⁺), superoxide (O₂^-), and hydroxyl radicals (OH) worked in the photo-degradation, while O₂^- played the most important role. Furthermore, intermediates identification and density functional theory (DFT) calculations were used to explore the degradation mechanism. For both DMP and DEP, the reactive oxygen species (ROS, including O₂^- and OH) were responsible for the hydroxylation of benzene ring and the breaking of the aliphatic chain, while h⁺ was prone to break the aliphatic chain. This work is expected to provide new insights on the photocatalytic mechanism of stannate perovskites for environmental remediation.

Iron cobalt and nitrogen co-doped carbonized wood sponge for peroxymonosulfate activation: Performance and internal temperature-dependent mechanism

The directional regulation of oxidation capacity in the carbon-based peroxymonosulfate (PMS) activation system is a promising strategy for wastewater purification. In this work, a novel iron cobalt and nitrogen co-doped carbonized wood sponge (FeCoNCWS) was developed. A superb catalytic performance for sulfamethoxazole (SMX) degradation (∼100.0%) was obtained within 30 min in FeCoNCWS800/PMS system at 60 °C. Besides, the reactive oxygen species (ROS) contribution was verified at different reaction temperatures. Specifically, the primary roles of sulfate and hydroxyl radicals (SO₄^- and OH) in SMX removal weakened, while the secondary role of singlet oxygen (¹O₂) in SMX degradation was enhanced with the rise of reaction temperature in FeCoNCWS800/PMS system. Interestingly, defects, graphitic N and carbonyl (CO) groups were vital active sites for PMS activation to produce ¹O₂, which was facilitated at higher reaction temperature. Besides, the metal sites were identified as PMS activators for SO₄^- and OH generation, which was promoted under lower reaction temperature. The findings revealed a novel internal temperature-dependent PMS activation mechanism, which can help to regulate the oxidation capacity of PMS activation system rationally for pollutant degradation.

Waste preserved wood derived biochar catalyst for promoted peroxymonosulfate activation towards bisphenol A degradation with low metal ion release: The insight into the mechanisms

The rational disposal of waste preserved wood is of great significance since its embedded metals (Cu, As, and Cr) pose potential threat to environment and human health. In this study, a biochar catalyst derived from waste preserved wood (PWB) was prepared for the degradation of bisphenol A (BPA) via peroxymonosulfate (PMS) activation. The PWB exhibited prominent catalytic degradation capability towards BPA compared with common wood derived biochar (CWB). Further tests and analysis elucidated that both radical species (OH) and non-radical species (¹O₂) were generated by the PWB/PMS system, whereas only ¹O₂ was detected in CWB/PMS system. Specifically, the metal compounds, especially metallic Cu in the PWB activated PMS via radical pathway, and the CO groups in the biochar generated the non-radical pathway, the coexistence of which resulted in higher BPA degradation rate in PWB/PMS system. It was also demonstrated that the heavy metal ion leaching (As and Cr) in PWB/PMS system was negligible. Furthermore, the biochar could effectively inhibit the leakage of oxidized Cu ions. This study provides a novel approach to prepare high-efficient carbocatalysts for organic pollutant degradation in water, which also enables the waste preserved wood with an environmental nondestructive mode of dispatch.

Brønsted-acid sites promoted degradation of phthalate esters over MnO2: Mineralization enhancement and aquatic toxicity assessment

Advanced oxidation processes (AOPs) are important technologies for aqueous organics removal. Despite organic pollutants can be degraded via AOPs generally, high mineralization of them is hard to achieve. Herein, we synthesized a manganese oxide nanomaterial (H2-OMS-2) with abundant Brønsted-acid sites via ion-exchange of cryptomelane-type MnO₂ (OMS-2), and tested its catalytic performance for the degradation of phthalate esters via peroxymonosulfate (PMS) activation. About 99% of dimethyl phthalate (DMP) at a concentration of 20 mg/L could be degraded within 90 min and 82% of it could be mineralized within 180 min over 0.6 g/L of catalyst and 1.8 g/L of PMS. The catalyst could activate PMS to generate SO₄^-˙ and ·OH as the dominant reactive oxygen species to reach complete degradation of DMP. Especially, the higher TOC removal rate was obtained due to the rich Brønsted-acid sites and surface oxygen vacancies on the catalyst. Kinetics and mechanism study showed that Mn^II/Mn^III might work as the active sites during the catalytic process with a lower reaction energy barrier of 55.61 kJ/mol. Furthermore, the catalyst could be reused for many times through the regeneration of the catalytic ability. The degradation and TOC removal efficiencies were still above 98% and 65% after seven consecutive cycles, respectively. Finally, H2-OMS-2-catalyzed AOPs significantly reduced the organismal developmental toxicity of the DMP wastewater through the investigation of zebrafish model system. The present work, for the first time, provides an idea for promoting the oxidative degradation and mineralization efficiencies of aqueous organic pollutants by surface acid-modification on the catalysts.

Insights into the mechanism of redox pairs and oxygen vacancies of Fe2O3@CoFe2O4 hybrids for efficient refractory organic pollutants degradation

The core-shell Fe₂O₃@CoFe₂O₄ hybrids microspheres with abundant oxygen vacancies were synthesized through in-situ ion exchange-calcination method and employed to induce peroxymonosulfate (PMS) to eliminate organic pollutants. The superior catalytic activity and stability of Fe₂O₃@CoFe₂O₄ were attributed to the synergistic effects of M²⁺/M³⁺ (M denotes Co or Fe) redox cycles. SO₄^·-, ·OH, O₂^·- and ¹O₂ were proved to be the main reactive oxygen species (ROS) involved in the phenol degradation process through quenching experiments and EPR measurements, while the surface-bound SO₄^·- played a dominant role. Trace metal ions leached during the reaction enhanced the PMS activation, and the oxygen vacancies electron transfer process played a critical role in the formation of O₂^·-/¹O₂ and the cycle of M²⁺/M³⁺ redox pairs. The formation of ROS and function of ¹O₂ were also revealed from bulk reaction and interface reaction. This study highlighted the simultaneous evolution of PMS reduction and oxidation to generate ROS, which provided an insight into the efficient catalytic degradation of persistent organic pollutants (POPs).

Preparation and properties of natural rubber composite with CoFe2O4-immobilized biomass carbon

Designing versatile rubber as a multifunctional elastomer is of great importance, incorporating it with biomass-derived nanoblocks will mitigate environmental challenges. Here biosynthesized natural rubber (NR) composites with CoFe2O4-immobilized biomass carbon (BC) derived from macadamia nutshells were fabricated by facile mechanical mixing. Morphological analysis indicates that CoFe2O4 nanoparticles are uniformly anchored on the surface of BC, forming intact electromagnetic loss networks in NR matrix. As a consequence, the as-fabricated NR/CoFe2O4@BC composites demonstrate enhanced mechanical, thermal, and electromagnetic performance. Particularly, NR/CoFe2O4@BC composite shows the best microwave attenuation capacity when CoFe2O4@BC loading is 40 phr, with the minimum reflection loss (RL) of −35.00 dB and effective absorption bandwidth (RL < −10 dB) of 1.60 GHz. All results indicate that this work open new paradigm for multiple applications based on biosynthetic elastomer with the sustainable biomass derived nanoblocks.

Preparation, characterization, and applications of Fe-based catalysts in advanced oxidation processes for organics removal: A review

Fe-based catalysts as low-cost, high-efficiency, and non-toxic materials display superior catalytic performances in activating hydrogen peroxide, persulfate (PS), peracetic acid (PAA), percarbonate (PC), and ozone to degrade organic contaminants in aqueous solutions. They mainly include ferrous salts, zero-valent iron, iron-metal composites, iron sulfides, iron oxyhydroxides, iron oxides, and supported iron-based catalysts, which have been widely applied in advanced oxidation processes (AOPs). However, there is lack of a comprehensive review systematically reporting their synthesis, characterization, and applications. It is imperative to evaluate the catalytic performances of various Fe-based catalysts in diverse AOPs systems and reveal the activation mechanisms of different oxidants by Fe-based catalysts. This work detailedly summarizes the synthesis methods and characterization technologies of Fe-based catalysts. This paper critically evaluates the catalytic performances of Fe-based catalysts in diverse AOPs systems. The effects of solution pH, reaction temperature, coexisting ions, oxidant concentration, catalyst dosage, and external energy on the degradation of organic contaminants in the Fe-based catalyst/oxidant systems and the stability of Fe-based catalysts are also discussed. The activation mechanisms of various oxidants and the degradation pathways of organic contaminants in the Fe-based catalyst/oxidant systems are revealed by a series of novel detection methods and characterization technologies. Future research prospects on the potential preparation means of Fe-based catalysts, practical applications, assistive technologies, and impact in AOPs are proposed.

Co/N co-doped carbonized wood sponge with 3D porous framework for efficient peroxymonosulfate activation: Performance and internal mechanism

Renewable wood sponge with lamellar structure, compressibility and three-dimensional porous frameworks exhibits excellent functionalization application potential in various fields. Herein, cobalt and nitrogen (Co/N) co-doped carbonized wood sponge (CoNCWS800) was prepared successfully for peroxymonosulfate (PMS) activation to degrade sulfamethoxazole (SMX). The CoNCWS800 material exhibited admirable catalytic activity in PMS activation to oxidize SMX molecules (99.7% within 60 min). Electron paramagnetic resonance (EPR) analysis, quenching tests and electrochemical experiments confirmed the existence of both radical (SO₄^·-,·OH and O₂^·-) and non-radical (¹O₂ and direct charge transfer) pathways during the SMX degradation process. Co species were verified as major contributors for the generation of multiple radicals via activating PMS. Surface defective structure and ketonic CO groups performed the positive linear correlation with reaction kinetic constants, revealing the critical role of the two active sites in PMS activation via non-radical process. This study provides a unique insight in PMS activation mechanism via both radical and non-radical pathways of wood sponge-based functional materials.

Insights into the degradation of emerging organic pollutants by peroxydisulfate activated with Co3O4@NiO: role of each component and catalytic mechanism

A novel Co3O4@NiO as a high-efficiency catalyst was employed to activate peroxydisulfate for degrading antibiotics, and the catalytic mechanism was investigated.

Bisphenol A degradation by peroxymonosulfate photo-activation coupled with carbon-based cobalt ferrite nanocomposite: Performance, upgrading synergy and mechanistic pathway

Cobalt ferrite (CoFe₂O₄, CF) nanoparticles were anchored on the multiwalled carbon nanotube (MWCNT) for synthesis of CF@MWCNT nanocomposite and enhancing the catalytic activity of CF. After well characterization, it was applied as a catalyst towards photo-activation peroxymonosulfate (PMS) for degradation of bisphenol A (BPA). Based on the identified intermediates, a possible degradation pathway was proposed for BPA. CF@MWCNT coupled with PMS and UV (i.e., CF@MWCNT/PMS/UV) exhibited a better performance than homogeneous UV-assisted PMS processes under Fe and Co ions. A significant synergy on the degradation of BPA was observed in the simultaneous application of catalyst, UV light and PMS. Under optimum conditions, the removal efficiencies of 100 and 72.6% were attained respectively for BPA and TOC by CF@MWCNT/PMS/UV within 60 min reaction. These efficiencies were decreased to 88 and 61% after five times use of catalyst, respectively. The leaching of metal ions dissolved from the catalyst was slight during cyclic utilization of catalyst, confirming high stability of CF@MWCNT. In this process, the participation of radical mechanisms was approximately 60%, which SO₄^•- and HO^• species contributed as predominant oxidizing reactive species. It also showed the excellent catalytic performance towards decomposition of persulfate and hydrogen peroxide. Overall, UV-assisted PMS catalyzed by CF@MWCNT exhibited a good catalytic performance and so it can be potentially introduced as a promising method for efficient treatment of water contaminated by BPA.

Enhanced degradation of bisphenol A by mixed ZIF derived CoZn oxide encapsulated N-doped carbon via peroxymonosulfate activation: The importance of N doping amount

In this study, mixed metal cobalt zinc oxide embedded nitrogen enriched porous carbon composites (CoZnO-PC) were prepared via pyrolyzing polyvinylpyrrolidone (PVP) encapsulated Co, Zn-bimetal centered zeolitic imidazolate frameworks (ZIF). The prepared composites were then used to activate peroxymonosulfate (PMS) for bisphenol A (BPA) removal in water. When mole ratio of Co/Zn was 2/1, the resulted Co₂Zn₁O-PC possessed spinel structure with prominent degradation capability, in which the introduction of Zn accelerated the PMS activation performance of Co through establishing bimetal synergistic interactions. Both radical and non-radical activation pathways were existed in the Co₂Zn₁O-PC/PMS system, in which Co₂Zn₁O dominated the radical pathway whereas PC dominated the non-radical way. Since PVP contained abundant nitrogen atoms and could form strong coordination interactions with the ZIF precursor, the introduction of PVP in the ZIF precursor prevented pore collapsing during pyrolysis process, as well as enhancing the nitrogen content in the pyrolzed composites, which significantly promoted the generation of singlet oxygen. With combined pathways, the Co₂Zn₁O-PC/PMS system showed a wide pH application range with promising mineralization rate. Meanwhile, the spinel-structured Co₂Zn₁O-PC was magnetically separable with desirable recyclability. This study presents a novel composite with remarkable performance for the removal of refractory organic pollutants in municipal wastewater.

Construction of ZIF@electrospun cellulose nanofiber derived N doped metallic cobalt embedded carbon nanofiber composite as binder-free supercapacitance electrode

In this study, binder-free hybrid supercapacitance electrode based on N, Co co-doped porous carbon polyhedral encapsulated carbon nanofibers composites (N-Co/CNF) was prepared through pyrolyzing cobalt based zeolitic imidazolate frameworks (ZIF-67(Co)) incorporated electrospun cellulose nanofibers. With rational combination of the conductivity provided by cellulose derived CNF, promising porosity provided by CNF and ZIF-67(Co) derived porous carbon and uniformly dispersed metallic cobalt nanoparticles, the N-Co/CNF displayed excellent electrochemical properties. Specifically, the N-Co/CNF pyrolyzed at 800 °C possessed superior electrochemical performance in 1 M H₂SO₄ electrolyte, including a specific capacitance of ~433 F/g and 84% of the capacitance retention after 3000 consecutive charge-discharge cycles. This significantly exceeded the performance of cellulose derived CNF based pure carbonaceous electrode. Therefore, the present study provides a new view on the construction of high performance hybrid supercapacitance electrode which introduces renewable biomass resources like cellulose as both carbonaceous material precursors and conductive binders.

A review on efficient removal of phthalic acid esters via biochars and transition metals-activated persulfate systems

As emerging contaminants, PAEs (Phthalic Acid Esters or Phthalate Esters) have been extensively utilized in industrial production to soften the rigid plastics (plasticizers), and their related products are widely distributed in our daily life. The PAEs can readily transfer from the products to the surrounding environment due to not being chemically bound to the products. In this study, we analyzed the PAEs' properties, usage, and consumption in the world, as well as toxicity to human beings. As endocrine-disrupting chemicals (EDCs), PAEs can disturb the normal hormones reactions, resulting in developmental and reproductive problems. Thus, we have to concern the removal strategies of PAEs. We summarized two novel approaches, including biochars and persulfate (PS) oxidation for effectively removing PAEs in the literature. Their characteristics, removal mechanisms, and the main impact factors on the removal of PAEs were highlighted. Moreover, transition metal-activated PS showed good performance on PAEs degradation. Furthermore, the synergy of biochars and transition metals-PS can overcome the disadvantages of a single approach, and show better performance on the removal of PAEs. Finally, we put forward vital strategies to update two approaches (including the combined) for enhancing the removal of PAEs. It is expected that the researchers or scientists can get a hint on effectively remediating PAEs-contaminated sites via the biochars' sorption/transition metals-PS or the combined two from this review paper.

Fe3C-porous carbon derived from Fe2O3 loaded MOF-74(Zn) for the removal of high concentration BPA: The integrations of adsorptive/catalytic synergies and radical/non-radical mechanisms

In this study, novel Fe₃C-porous carbon composites (Fe₃C-C) were prepared via the pyrolysis of Fe₂O₃ loaded MOF-74(Zn), which could integrate both strong adsorption properties and excellent peroxymonosulfate (PMS) activating performance for the removal of bisphenol A (BPA) in water. Results indicated that the composite obtained at 1000 °C (Fe₃C-C1000) exhibited optimal catalytic capability. Specifically, 0.1 mM BPA could be completely removed by 0.1 g/L Fe₃C-C1000 within 10 min after the adsorption enrichment. Afterwards, the mechanism of Fe₃C-C/PMS system was unveiled based on quenching tests, electron spin resonance analysis, electrochemical analysis, PMS consumption detection and solvent exchange (H₂O to D₂O) test. The BPA degradation pathways were also analyzed through identifying its decomposition intermediates. Results showed that the Fe₃C and porous carbon constituents could activate PMS via radical and non-radical mechanisms respectively, and BPA was readily degraded through both pathways. Additionally, it was found that the Fe₃C-C1000/PMS system could maintain conspicuous catalytic performance in a variety of complicated water matrices with wide pH application range and long-time use stability. This study suggests a new insight for the design and development of novel catalyst which can be used for the removal of refractory organic contaminants with high concentrations in water media.

Associations between medication use and phthalate metabolites in urine and follicular fluid among women undergoing in vitro fertilization

BACKGROUND

Phthalates, which are used as excipients of drugs, have been related to adverse reproductive outcomes. However, the relationships between medication use and phthalate exposure among women undergoing in vitro fertilization (IVF) have not been studied.

OBJECTIVE

To investigate the associations between the medication intake and phthalate metabolites in urine and follicular fluid (FF).

METHOD

Eight phthalate metabolites were measured in urine and FF samples from 274 women undergoing IVF using liquid chromatography-tandem mass spectrometry. Information on recent medication intake was obtained via interview by trained staff. We constructed generalized linear regression models to examine the associations of medication intake with phthalate metabolite concentrations and dose-response relationships between the number of medicines used and metabolite concentrations in two matrices.

RESULTS

Four of 10 drugs were used by more than 10% of the participants, including vitamins (23.0%), traditional Chinese medicine (TCM, 22.3%), antioxidants (12.4%) and amoxicillin (10.2%). Participants who had used TCM had 26.0% (95% CI: 0.0, 58.8%), 32.6% (95% CI: 4.2, 68.8%) and 32.3% (95% CI: 2.6, 70.6%) higher urinary mono-n-butyl phthalate (MBP), mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) and mono(2-ethyl-5-oxohexyl) phthalate (MEOHP) concentrations, respectively, than those who had not. Antioxidant intake was associated with a 30.6% (95% CI: -48.5, -6.6%) decrease in the urinary MBP concentration. Compared with non-users, women who reported the use of medicines had 53.2% (95% CI: 2.7, 128.5%) higher concentrations of MMP and a 37.7% (95% CI: -60.7, -1.5%) lower level of MBP in FF, respectively.

CONCLUSION

Our data suggest that the intake of some medications may increase phthalate exposure among women undergoing IVF.

Efficient degradation of clofibric acid by heterogeneous catalytic ozonation using CoFe2O4 catalyst in water

CoFe₂O₄ (Cobalt ferrite, CF) nanoparticles were prepared, well characterized and applied as efficient solid catalyst in catalytic ozonation, named CF/O₃ process, for the removal of emerging organic contaminants (EOCs). The degradation and mineralization of clofibric acid (CA) in CF/O₃ process were dramatically enhanced in comparison with those under the O₃ system. Surface hydroxyl groups (HGs) were considered as an important factor for ozone decomposition and the reactive oxygen species (ROS) on the catalyst surface were mainly responsible for CA elimination. The contribution and formation of ROS, including hydroxyl radicals (^•OH), especially superoxide radicals (O₂^•-), singlet oxygen (¹O₂), and hydrogen peroxide (H₂O₂) were evaluated, and a rational mechanism was elucidated accordingly. Probable degradation pathway of CA was proposed according to the organic intermediates identified. The acute toxicity of the treated solution increased during the first 15 min and then declined rapidly and nearly disappeared as the reaction proceeded. In addition, acceptable catalytic performance of CF/O₃ can be obtained for the treatment of other EOCs and the treatment of natural surface water spiked with CA. This work presents an efficient and promising catalytic ozonation technique for the elimination of EOCs in complex water matrices.

Burgeoning prospects of biochar and its composite in persulfate-advanced oxidation process

In the last decade, more and more refractory organic contaminants with severe health risks have been detected in the aquatic ecosystem. Sulfate radical (SO₄^·-)-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.

Remediation strategies for mitigation of phthalate pollution: Challenges and future perspectives

Phthalates are a group of emerging xenobiotic compounds commonly used as plasticizers. In recent times, there has been an increasing concern over the risk of phthalate exposure leading to adverse effects to human health and the environment. Therefore, it is necessary to not only understand the current status of phthalate pollution, their sources, exposure routes and health impacts, but also identify remediation technologies for mitigating phthalate pollution. Present review article aims to inform its readers about the ever increasing data on health burdens posed by phthalates and simultaneously highlights the recent advancements in research to alleviate phthalate contamination from environment. The article enumerates the major phthalates in use today, traces their environmental fate, addresses their growing health hazard concerns and largely focus on to provide an in-depth understanding of the different physical, chemical and biological treatment methods currently being used or under research for alleviating the risk of phthalate pollution, their challenges and the future research perspectives.