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Microcystin-LR (MC-LR) is an extremely poisonous cyanotoxin that poses a threat to ecosystems and human health. MC-LR has been reported as an enterotoxin. The objective of this study was to determine the effect and the mechanism of subchronic MC-LR toxicity on preexisting diet-induced colorectal damage. C57BL/6J mice were given either a regular diet or a high-fat diet (HFD) for 8 weeks. After 8 weeks of feeding, animals were supplied with vehicle or 120 μg/L MC-LR via drinking water for another 8 weeks, and their colorectal were stained with H&E to detect microstructural alterations. Compared with the CT group, the HFD and MC-LR + HFD-treatment group induced a significant weight gain in the mice. Histopathological findings showed that the HFD- and MC-LR + HFD-treatment groups caused epithelial barrier disruption and infiltration of inflammatory cells. The HFD- and MC-LR + HFD-treatment groups raised the levels of inflammation mediator factors and decreased the expression of tight junction-related factors compared to the CT group. The expression levels of p-Raf/Raf and p-ERK/ERK in the HFD- and MC-LR + HFD-treatment groups were significantly increased compared with the CT group. Additionally, treated with MC-LR + HFD, the colorectal injury was further aggravated compared with the HFD-treatment group. These findings suggest that by stimulating the Raf/ERK signaling pathway, MC-LR may cause colorectal inflammation and barrier disruption. This study suggests that MC-LR treatment may exacerbate the colorectal toxicity caused by an HFD. These findings offer unique insights into the consequences and harmful mechanisms of MC-LR and provide strategies for preventing and treating intestinal disorders. [ABSTRACT FROM AUTHOR]

Microcystin-LR (MC-LR) contamination is a worldwide environmental problem that poses a grave threat to the water ecosystem and public health. Exposure to MC-LR has been associated with the development of intestinal injury, but there are no effective treatments for MC-LR-induced intestinal disease. Probiotics are "live microorganisms that are beneficial to the health of the host when administered in sufficient quantities". It has been demonstrated that probiotics can prevent or treat a variety of human diseases; however, their ability to mitigate MC-LR-induced intestinal harm has not yet been investigated. The objective of this study was to determine whether probiotics can mitigate MC-LR-induced intestinal toxicity and its underlying mechanisms. We first evaluated the pathological changes in colorectal tissues using an animal model with sub-chronic exposure to low-dose MC-LR, HE staining to assess colorectal histopathologic changes, qPCR to detect the expression levels of inflammatory factors in colorectal tissues, and WB to detect the alterations on CSF1R signaling pathway proteins in colorectal tissues. Microbial sequencing analysis and screening of fecal microorganisms differential to MC-LR treatment in mice. To investigate the role of microorganisms in MC-LR-induced colorectal injury, an in vitro model of MC-LR co-treatment with microorganisms was developed. Our findings demonstrated that MC-LR treatment induced an inflammatory response in mouse colorectal tissues, promoted the expression of inflammatory factors, activated the CSF1R signaling pathway, and significantly decreased the abundance of Lactobacillus. In a model of co-treatment with MC-LR and Lactobacillus fermentum (L. fermentum), it was discovered that L. fermentum substantially reduced the incidence of the colorectal inflammatory response induced by MC-LR and inhibited the protein expression of the CSF1R signaling pathway. This is the first study to suggest that L. fermentum inhibits the CSF1R signaling pathway to reduce the incidence of MC-LR-induced colorectal inflammation. This research may provide an excellent experimental foundation for the development of strategies for the prevention and treatment of intestinal diseases in MC-LR. [ABSTRACT FROM AUTHOR]

Highlights: [•] A Ca-montmorillonite was modified with DDTMA and HDTMA through direct ion exchange. [•] The prepared organoclays were characterized by XRD and BET instruments. [•] The adsorption conditions for BPA of organoclays were systematically studied. [•] The study provides a pathway for the removal of BPA from contaminated waters. [ABSTRACT FROM AUTHOR]

• The development and progression of NAFLD by common pollutants in water is reviewed. • Features in response to each environmental contaminant are elucidated. • The new perspective of joint toxicity of pollutants in water bodies is put forward. The global prevalence of nonalcoholic fatty liver disease (NAFLD) has been increasing rapidly in recent years, which is now estimated to be over 25%. NAFLD is one of the most common chronic liver diseases in the world. At present, with the rapid development of economy and industrialization, many chemicals are released into the environment. These chemical contaminants in the environment might cause harm to human health and result in lipid metabolism disorder during long-term exposure. Moreover, the incentive of many NAFLD cases is unknown, and the environmental risk factors of NAFLD need to be urgently identified. Hence, we focus on the impacts of several popular environmental contaminants in water environment on the development and progression of NAFLD. These contaminants mainly include microcystins (MCs), disinfection by-products (DBPs), heavy metals (HMs), dioxins and polychlorinated biphenyls (PCBs). Through analyzing a great many epidemiological and toxicological studies, we have found positive associations between NAFLD and chronic exposure to these contaminants at the environmental levels. This review may enhance the understanding of liver damage caused by environmental pollutants, which are considered as tangible environmental risk factors for NAFLD. [ABSTRACT FROM AUTHOR]

[Display omitted] • A ternary 3D "PIZZA"-like Bi 2 MoO 6 -TiO 2 /diatomite composite was synthesized. • An adsorption-photocatalysis system was constructed by the instruction of diatomite. • Excellent photocatalytic mineralization property of HCHO was obtained under visible light. • The effect of water on the mineralization of HCHO was studied via in-situ DRIFTs analysis. • The O 2 and H 2 O molecules were involved in the photocatalytic mineralization process of HCHO. The application of TiO 2 -based photocatalysts in air pollution control has attracted much attention thanks to their advantageous green and sustainable performance. However, how to improve the degradation efficiency under visible light is still challenging. Herein, we report a ternary three-dimensional "PIZZA"-like Bi 2 MoO 6 -TiO 2 /diatomite (BTD) composite with high-efficient mineralization and recycling performance towards gaseous formaldehyde (HCHO) under visible light. The high-efficient adsorption-photocatalysis collaborative system with intimate interface combination is successfully established among Bi 2 MoO 6 (BMO), TiO 2 and diatomite. The HCHO mineralization rate constant of BTD-1:2 composite is up to around 4.03 times and 2.18 times higher than those of bare BMO and binary Bi 2 MoO 6 -TiO 2 composite, respectively. It is indicated that the introduction of diatomite increases active sites and plays the vital role in the improvement of photocatalysis. In addition, the photogenerated holes (h+) and hydroxyl radical (OH) are proved to be the main active species for HCHO mineralization. Furthermore, there is a competitive adsorption relationship between water (H 2 O) molecules and HCHO molecules, and both H 2 O molecules and oxygen (O 2) molecules participated in the reaction of HCHO mineralization based on in-situ DRIFTs spectra analysis. Our work would give a new perspective on gaseous HCHO purification. [ABSTRACT FROM AUTHOR]

Highlights: [•] An Arizona Ca-montmorillonites was modified with DDDMA through direct ion exchange. [•] The obtained organoclays were characterized by XRD, TEM, TG, and hot stage IES. [•] The structural geometry and thermal properties of organoclays were studied. [•] Organic SAz-2 Ca-montmorillonites showed potential prospects in the polymer industry. [ABSTRACT FROM AUTHOR]

Highlights: [•] TiO2/AST composite was synthesized by hydrolysis–deposition method. [•] The composite was characterized by SEM, TEM, XRD, EDS, XPS, and FTIR. [•] TiO2 particles coated on AST were mixed crystal phases of rutile and anatase. [•] TiO2/AST composite showed good photocatalytic activity for the removal of Cr(VI). [ABSTRACT FROM AUTHOR]

Diatomite-based X zeolite was obtained and its crystallinity, morphology, and interface properties were investigated by XRD, BET, SEM, EDS, and XRF. The obtained X zeolite possessed a unique meso-microporous structure and showed good ion exchange properties for Cu2+ and Zn2+. The pseudo-second-order model and Langmuir isotherm model can best describe the adsorption kinetics and isotherms of Cu2+ and Zn2+, respectively. The maximal adsorption capacities of X zeolite for Cu2+ and Zn2+ were 146 and 195 mg/g at 323 K, respectively. Meanwhile, the adsorption process for Cu2+ and Zn2+ were chemical adsorption and ion exchange, respectively. Furthermore, the adsorption data turned out to be an endothermic and spontaneous process. Compared with other reported materials, the adsorption capacity of X zeolite synthesized from diatomite was among the highest. Therefore, it could be a promising adsorbent for the disposal of wastewater that contains metal ions. [ABSTRACT FROM AUTHOR]

[Display omitted] • The synergistic effect of natural minerals for persulfate activation were reviewed. • The mechanism of persulfate activation and contaminants degradation were summarized. • We pointed out that the major challenges and direction of mineral-based catalysts. • This review is meaningful for the high-value-added application and functional specialization of minerals. The severity of environmental pollution poses a serious threat to human health, and especially organic pollution is more complex and difficult to treat compared to heavy metal pollution. Nowadays, the persulfate-based advanced oxidation processes receive more and more attention due to high efficiency, strong controllability, easy operation, and economic competitiveness, which is generally employed for the efficient degradation of organic contaminants. Natural minerals possess the characteristics of low-cost, easy availability, environmental friendliness, non-toxic, special structural effects, etc., which have played a critical role and could be the promising alternative to traditional catalysts for persulfate activation. First, this review retrospects the research status of natural minerals and mineral-based catalysts for persulfate activation to degrade organic contaminants, i.e., pyrite, mackinawite, copper sulfide, kaolinite, and montmorillonite. Then, the mechanisms of persulfate activation by natural minerals and mineral-based catalysts to generate the reactive oxygen species including SO 4 •−, •OH, •O 2 −, 1O 2 , and surface reactive complex for contaminants degradation are systematically summarized. Finally, we discussed the further application of natural minerals in activating persulfate as well as the future research frontiers for practical environmental remediation, i.e., the synthesis and characterization of mineral-based catalysts dominated by non-radical pathway, the large-scale application of PDS with low-cost, the surface modification of mineral-based catalysts with amphiphilicity, as well as the more efficient catalysts possessing nano-restricted domain catalytic effect. The development and expansion of novel and efficient mineral-based catalysts with enhanced synergistic effects would provide new opportunities for persulfate activation in environmental remediation. [ABSTRACT FROM AUTHOR]

Highlights: [•] We have prepared three amorphous silica minerals as supports for TiO2 catalysis. [•] We characterized by XRD, SEM, FT-IR, TEM and XPS. [•] We investigated the UV-assisted degradation of Rhodamine B (RhB). [•] TiO2/DE photocatalyst exhibits better catalytic performance at different calcined temperatures. [ABSTRACT FROM AUTHOR]

The catalytic membrane, which combines the physical barrier and peroxymonosulfate (PMS)/visible light (Vis)-induced catalytic oxidation functionalities while minimizing biofouling, exhibits great promise as a material for the removal of persistent organic pollutants from wastewater. In this study, three catalytic membranes composed of 2D/2D hybrid g-C 3 N 4 /kaolinite with nitrogen vacancies and modified with different iron species (γ-FeOOH nanosheets, Fe 2 O 3 quantum dots, and Fe single atoms) were prepared via vacuum filtration. Evaluation of the catalytic performance demonstrated that γ-FeOOH nanosheets-modified sample exhibited a relatively higher water flux (258.13 L m-2 h-1). In contrast, Fe single atom-modified sample achieved improved bisphenol A removal efficiency (97.39%) under the PMS/Vis synergetic system. Interestingly, the Fe 2 O 3 quantum dots-modified sample exhibited the highest rate constant based on the retention time. Furthermore, the Fe single atom-modified sample showed consistent removal of bisphenol A, reaching nearly 100% during continuous-flow operation for 180 min, while maintaining a flux of approximately 200 L m-2 h-1. Quenching experiments suggested that •O 2 −, 1O 2 , and h+ were the most important oxidizing species involved in the reaction of the three membranes. Statistical analysis indicated that variations in the average pore size of the membranes were key factors influencing the catalytic activity. Overall, this study offers an in-depth insight into the systematic and quantitative assessment of 2D/2D hybrid g-C 3 N 4 /layered clay-based catalytic membranes for wastewater treatment. [Display omitted] • The catalytic performance of three iron species-based membranes for bisphenol A removal were compared. • Fe single atom modified membrane showed more superior catalytic performance. • Fe 2 O 3 quantum dots modified membrane possessed the largest rate constant. • The catalytic performance was significantly correlated with surface area and average pore size. [ABSTRACT FROM AUTHOR]

Distinctive Cr-MOF@Da composites have been constructed using chromium-based metal-organic frameworks (MOFs) and diatomite (Da). The new materials have hierarchical pore structures containing micropores, mesopores and macropores. We have synthesized various morphologies of the MOF compound Cr-MIL-101 to combine with Da in a one-pot reaction step. These distinctive hierarchical pore networks within Cr-MIL-101@Da enable exceptional adsorptive performance for a range of molecules, including hydrogen (H2), carbon dioxide (CO2) and water (H2O) vapor. Selectivity for H2 or CO2 can be moderated by the morphology and composition of the Cr-MIL-101 included in the Cr-MOF@Da composite. The encapsulation and growth of Cr-MIL-101 within and on Da have resulted in excellent water retention as well as high thermal and hydrolytic stability. In some cases, Cr-MIL-101@Da composite materials have demonstrated increased thermal stability compared with that of Cr-MIL-101; for example, decomposition temperatures >340 ℃ can be achieved. Furthermore, these Cr-MIL-101@Da composites retain structural and morphological integrity after 60 cycles of repeated hydration/dehydration, and after storage for more than one year. These characteristics are difficult to achieve with many MOF materials, and thus suggest that MOF–mineral composites show high potential for practical gas storage and water vapor capture. [ABSTRACT FROM AUTHOR]

Novel oxygen vacancy-rich amorphous TiO 2 -BiOBr-sepiolite composite with enhanced photocatalytic removal for indoor HCHO and oxytetracycline under visible light was successfully fabricated by a facile one-pot solvothermal method. This work could provide a new insight for designing and constructing highly active photocatalysts for the practical elimination of pharmaceutical and personal care products (PPCPs) as well as volatile organic compounds (VOCs). • Novel oxygen vacancy-rich amorphous TiO 2 -BiOBr-sepiolite composite was synthesized. • The composite shows superior photodegradation efficiency towards HCHO and oxytetracycline. • The photocatalytic process is mainly governed by the photoinduced holes. • Potential mechanisms for the enhanced activity of composite were analyzed. • The plausible degradation pathway for oxytetracycline was proposed. Herein, a novel oxygen vacancy-rich amorphous TiO 2 -BiOBr-sepiolite composite was synthesized through a facile one-pot solvothermal method. Under visible light, it exhibited enhanced adsorption and photocatalytic removal activity towards gaseous formaldehyde, whose reaction rate constant is nearly 11.75, 3.44, 1.69, 2.18 and 6.27 times higher than those of amorphous TiO 2 , BiOBr, TiO 2 -BiOBr, oxygen vacancy-poor composite and P25, respectively. Moreover, it also displayed significantly improved photodegradation performance towards oxytetracycline under visible light. The improved photocatalytic activity is mainly ascribed to the synergy between the ternary heterogeneous structure and introduced oxygen vacancy, leading to the superior adsorption performance, extended visible-light adsorption scope and faster carriers' separation rate. The photogenerated holes are the dominant active species during the reaction process. Additionally, a plausible photocatalytic degradation pathway for oxytetracycline was also proposed. In general, this work provides a viable strategy of visible-light-driven photocatalyst for practical environmental remediation of indoor volatile organic compounds (VOCs) and pharmaceuticals and personal care products (PPCPs). [ABSTRACT FROM AUTHOR]

• Organo-montmorillonites (NZMts) modified by binary surfactant mixtures were synthesized. • The NZMts exhibit enhanced detoxification efficiency for both AFB1 and ZER. • The adsorption enhancement mechanism of NZMts was proposed. • This study provides new insight for multifunctional mycotoxin adsorbents. To solve the problem of simultaneous adsorption of polar and weak polar mycotoxins, organo-montmorillonites modified by binary surfactant mixtures (NZMts), including polyoxyethylene ether (OP-10) and lauramidopropyl betaine (LAB-35), were synthesized for the simultaneous removal of aflatoxin B 1 (AFB 1) and zearalenone (ZER). The microstructure, interface and pore structure characteristics of NZMts were investigated through different technologies. The results show that the obtained NZMts modified by binary surfactant mixtures have different structural configurations, higher carbon content and stronger hydrophobicity compared with organo-montmorillonites modified by single surfactant. More importantly, the obtained adsorbents show significant improvements on the detoxification efficiency of both AFB 1 and ZER. The pH has less effect on the adsorption of NZMts compared with the control samples modified by single surfactant, suggesting that NZMts are more stable in different pH environments. In addition, the adsorption mechanisms of NZMts to AFB 1 and ZER were proposed based on the characterizations and adsorption isotherms. It is indicated that NZMts combines with AFB 1 mainly through the hydrophobic interaction and ion dipole action, while with ZER mainly through hydrophobic interaction. The as-received NZMts with more hydrophobic property effectively enhance the adsorption capacities of weak polar and non-polar mycotoxins, providing a new orientation for multifunctional mycotoxin adsorbents. [ABSTRACT FROM AUTHOR]

• Novel BiOCl/TiO 2 /clinoptilolite composite photocatalyst was synthesized. • BiOCl/TiO 2 /clinoptilolite displayed excellent visible photocatalytic activity. • Carrier effect and heterojunction charged for photocatalytic enhancement. • This study provides a novel idea for ternary heterojunction construction. Novel BiOCl/TiO 2 /clinoptilolite composite was prepared via a homogeneous precipitation and calcination-crystallization process in this study. Through structural design and spatial assembly, the ternary composite based on clinoptilolite layer as well as the TiO 2 nano particles and BiOCl nano sheets was successfully synthesized. The prepared composite was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscope (HRTEM), X-ray photoelectron spectroscopy (XPS), N 2 isothermal adsorption-desorption test and electrochemical measurement, respectively. Compared with bare photocatalysts (i.e. TiO 2 and BiOCl), the composite exhibited enhanced photoactivity under visible light irradiation towards rhodamine B (RhB). Based on the pseudo-first-order kinetic constants, the photocatalytic performance of BiOCl/TiO 2 /clinoptilolite composite is around 48 and 11 times higher than that of pure TiO 2 and BiOCl, respectively. The enhanced photocatalytic properties of the composite should be attributed to the improved adsorption ability and the formation of the n -p heterojunction between BiOCl and TiO 2 , which is beneficial to establish the rapid adsorption-desorption system and promote the efficient separation of the photogenerated electron-hole pairs. The excellent visible-light-driven performance makes the BiOCl/TiO 2 /clinoptilolite composite possible to be utilized in the field of industrial wastewater treatment. [ABSTRACT FROM AUTHOR]

• CuFe 2 O 4 was uniformly anchored on kaolinite to activate peroxymonosulfate (PMS). • Sulfate radicals are the primary radical species in CuFe 2 O 4 /kaolinite/PMS system. • CuFe 2 O 4 /kaolinite exhibited high catalytic activity and low leaching of metal ions. • More hydroxyl groups and accessible reactive sites enhanced its catalytic activity. • Low leaching of metal is ascribed to Fe O Al bond between CuFe 2 O 4 and kaolinite. In this study, CuFe 2 O 4 /kaolinite catalysts were fabricated through a facile citrate combustion method and were evaluated for their efficiency to activate peroxymonosulfate (PMS) towards the destruction of bisphenol A (BPA). The prepared catalysts were systematically characterized to explore the relationship between their characteristics and catalytic activities. In general, higher specific surface area, larger pore volume, more hydroxyl groups, and more accessible reactive sites of 40%-CuFe 2 O 4 /kaolinite contributed to the greater catalytic activity in peroxymonosulfate activation for BPA degradation compared to bare CuFe 2 O 4. Monodispersed CuFe 2 O 4 nanoparticles were uniformly anchored on the surface of kaolinite with Fe O Al bond, which prevented leaching of metal ions and contributed to the excellent reusability. The sulfate radicals produced in the CuFe 2 O 4 /kaolinite/PMS system were proved as the predominant radical species through electron spin resonance (ESR) and radical quenching experiments. Based on the results of X-ray photoelectron spectroscopy (XPS) and attenuated total reflectance – Fourier transform infrared spectra (ATR-FTIR), two main possible pathways of sulfate radicals generation were proposed: the generation and decomposition of Cu(II)-(HO)OSO 3 − (Cu(II)/Cu(III) and Cu(III)/Cu(II) redox reaction) and the oxidation of Fe(II). Moreover, the BPA degradation pathway was proposed through the identification of transformation products. This work provides an interesting insight for PMS activation by the high-efficient natural mineral-based catalysts for wastewater reclamation. [ABSTRACT FROM AUTHOR]

A novel antibacterial thermoplastic polyurethane (TPU) nanofiber membrane was fabricated by electrospinning with the aid of Cu-loaded NaX zeolite (CuX), which showed excellent and long-lasting antibacterial activity against Escherichia coli (E. coli). The crystalline structure, morphology and composition of the obtained NaX zeolite, CuX and CuX/TPU nanofiber membrane were analyzed by X-ray diffraction (XRD), scanning electron microscope (SEM) and X-ray fluorescence (XRF), respectively. The antibacterial activity of CuX/TPU nanofiber membrane against E. coli was investigated by inhibition zone method and plate-counting method, and it is indicated that the inactivation efficiency was increased from 58.40 to 99.85% with increasing the addition of CuX from 5 to 30% in 4 h. The result of kinetics study indicated that the disinfection process accorded with the pseudo-first-order model. The possible antibacterial mechanism was also proposed that the released Cu2+ by CuX in nanofiber membrane destroyed the cell wall and penetrated plasma membrane of E. coli. It is expected that this CuX/TPU nanofiber membrane with excellent antibacterial activity would be a promising candidate for biomedical applications. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Natural kaolinite was used to activate peroxymonosulfate for the first time. • Surface-bonded and structural hydroxyl groups are responsible for PMS activation. • Kaolinite can be continuously reused to activate PMS without recovery. • OH and SO 4 − were identified as the primary reactive species. • The H 2 PO 4 − enhanced PMS decomposition and increased atrazine degradation. Abstract In this study, natural kaolinite, an abundant, low cost, thermally and chemically stable, and easily recyclable material was evaluated for the performance to activate peroxymonosulfate (PMS) by the degradation of atrazine. Based on radical quenching experiments and electron spinning resonance (ESR) spectra, hydroxyl radical (OH) and sulfate radical (SO 4 −) were identified to be the primary reactive species. The effects of catalyst loading, initial reaction pH, PMS dosage, initial atrazine concentration, and the presence of inorganic ions (Cl−, NO 3 −, HCO 3 − and H 2 PO 4 −) were also investigated in this work. Interestingly, the presence of H 2 PO 4 − enhanced the degradation efficiency of atrazine via promoting the decomposition of PMS. The transformation products were detected on a quadrupole time-of-flight liquid chromatography/mass spectrometer (Q-TOF-LC-MS) and the possible degradation pathway of atrazine was proposed. Based on comprehensive characterizations of crystal phase and crystallinity, porosity and pore structure, surface morphology, functional groups, and valence state of specific elements, the catalytic ability of natural kaolinite towards PMS is attributed to the abundant surface-bonded and structural hydroxyl groups. This study provides new insights of PMS activation by natural minerals for the degradation of refractory and deleterious contaminants in wastewater treatment. [ABSTRACT FROM AUTHOR]

Graphical abstract Novel ternary heterogeneous BiOCl/TiO 2 /sepiolite composite with enhanced visible-light-induced photoactivity towards TC was successfully fabricated by a mild hydrolysis precipitation method followed by the calcination crystallization process. The present study would inspire the exploration of similar novel design to synthesize other highly efficient visible-light photocatalysts for better applications in addressing environmental pollution issues. Abstract In this study, the novel ternary heterogeneous BiOCl/TiO 2 /sepiolite composite with enhanced visible-light-induced photocatalytic activity was synthesized via the hydrolysis precipitation method followed by a calcination crystallization process. The as-prepared samples were characterized by X-ray diffraction (XRD), UV–VIS diffused reflectance spectroscopy (DRS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), N 2 adsorption-desorption, X-ray photoelectron spectroscopy (XPS) and photoluminescence (PL), respectively. Compared with bare BiOCl and TiO 2 , the ternary heterogeneous structure in BiOCl/TiO 2 /sepiolite significantly improved the visible-light-induced photocatalytic performance towards tetracycline (TC), and also contributed to the separation efficiency and recyclability of the photocatalyst. In addition, the influence of the mass ratio of BiOCl in the composites was also discussed, and the optimal mass ratio is identified as 50% (m BiOCl /(m TiO2 + m BiOCl). Furthermore, TC degradation by-products were further detected by HPLC-MS/MS, and a possible degradation pathway was proposed. Besides, ESR (Electron spin resonance) results indicated that the main active radical species were photo-induced holes (h+) and superoxide radical (O 2 −) in the TC degradation process. Hence, the enhanced photocatalytic activity of the prepared ternary composite was mainly attributed to the remarkable synergistic effect within the BiOCl/TiO 2 /sepiolite ternary heterogeneous system, resulting in the superior adsorption activity, the outstanding visible-light response performance and the efficient separation of the photogenerated electron-hole pairs. It is speculated that the novel ternary heterogeneous BiOCl/TiO 2 /sepiolite composite would have a broad application prospect in the field of wastewater treatment. [ABSTRACT FROM AUTHOR]

Natural minerals are generally accepted as one of the most suitable carriers to support TiO 2 in photocatalytic and other applications because of their abundance, low cost, large surface area, and easy recyclability. Hence, in this work, a novel 0D/2D TiO 2 /kaolinite composite endowed with presence of oxygen vacancies and surface defect sites was synthesized through a mild sol-gel method combining with nitrogen induction. Ciprofloxacin (CIP) was taken as the main target organic pollutant to study the photocatalytic performance of the synthesized catalyst. The results showed that the nitrogen treated TiO 2 /kaolinite composite exhibited improving degradation performance for adsorption-photocatalytic elimination of CIP within broad radiation spectrum (200–800 nm). The synthesized composite exhibited enhanced reaction rate constant which is nearly 7.00, 2.54 and 3.13 times higher than that of bare TiO 2 treated with air under UV, solar, and visible light, respectively. Moreover, the newly prepared composite also exhibited significant enhancement towards the removal of formaldehyde under both UV and visible light. Radical scavenger experiments and ESR results indicated that holes should be the main oxidizing species within broad spectrum in the degradation system. The enhanced activity of nitrogen treated composite is mainly attributed to the induced oxygen vacancies as well as the intimate interface contact between TiO 2 and kaolinite, resulting in smaller grain size, higher light absorption ability, and faster carrier separation efficiency. It is expected that this high-efficiency composite photocatalyst based on natural minerals will be a promising candidate for the elimination of pharmaceutical and personal care products and volatile organic compounds within broad radiation spectrum. [ABSTRACT FROM AUTHOR]

Graphical abstract Novel CH 3 COOH functionalized TiO 2 /kaolinite composite was facilely prepared through a typical sol-gel method modified with CH 3 COOH treatment. Weak acid (CH 3 COOH) was utilized to activate the TiO 2 surface and generate more hydroxyl groups. Taken ciprofloxacin (CIP) as the target pollutant, both strongest adsorption ability and highest degradation efficiency were obtained compared with bare TiO 2 or TiO 2 /kaolinite composite under UV light and visible light, especially under UV light. Furthermore, density functional theory (DFT) calculations demonstrated that CH 3 COOH treatment might exert effect towards the transition and lifetime of electrons as well as contribute to the enhancement of the reactivity ability of TiO 2 and increase the catalytic properties. Enhancement mechanism and possible radicals' migration pathway was illustrated based on the characterizations (i.e. XRD, BET, UV–Vis, FTIR, Raman, etc.). Our study provides new insights into composite photocatalysts' surface adjustment and functional groups construction based on natural minerals. Highlights • Acetic acid was used to functionalize the TiO 2 /kaolinite surface. • Enhanced photocatalytic activity for ciprofloxacin within broad light spectrum was obtained. • DFT was used to explore the interface effect and the hydrogen function. • The enhancement mechanism was elucidated in this work. • This study provides novel idea for the synthesis of photocatalysts based on natural minerals. Abstract In this study, sol-gel method modified with acetic acid (CH 3 COOH) was employed to facilely synthesize hydrogen functionalized TiO 2 /kaolinite composite. Weak acid (CH 3 COOH) was used to modify the surface of TiO 2 /kaolinite composite in order to activate TiO 2 surface and generate more hydroxyl groups. The modified surface can act as Lewis acid sites to allow the physisorption of uncharged carboxyl acid groups, which is believed to be beneficial for electron injection and transfer. Using ciprofloxacin (CIP) as the target pollutant, in comparison with the use of strong acid such as hydrochloric acid (HCl) or sulfuric acid (H 2 SO 4), it was found that CH 3 COOH functionalized TiO 2 /kaolinite composite possessed the strongest adsorption ability and exhibited highest degradation efficiency under broad spectrum (200–800 nm). Moreover, the concentration of CH 3 COOH required is low (0.1 mol/L) in this work. The results show that the CH 3 COOH treated sample exhibited much higher degradation rates than bare TiO 2 or TiO 2 /kaolinite composite under both UV light and visible light. The kinetic constants under UV light were almost 2.61 and 1.57 times higher than those of TiO 2 and TiO 2 /kaolinite, respectively. According to the X-ray diffraction (XRD), N 2 adsorption-desorption isotherms, X-ray photoelectron spectroscopy (XPS), Fourier Transform infrared spectroscopy (FTIR) as well as Raman characterization results, it is revealed that the improved photocatalytic activity can be mainly attributed to the CH 3 COOH functionalization towards the TiO 2 /kaolinite composite. Furthermore, density functional theory (DFT) calculations were employed to explore the interface effect between TiO 2 and kaolinite as well as the function of newly introduced hydrogen on the surface of the composite, which significantly contributes to better understanding the function of CH 3 COOH in the constructed system. On the other hand, electron spin resonance (ESR) analysis suggests that the main oxidation species in the degradation process under broad light spectrum illumination was the holes. This study also provides information about the enhancement mechanism. New insights in photocatalysts synthesis and properties adjustment based on natural minerals for the elimination of organic contaminants of emerging concern in water was successfully introduced in the present study. [ABSTRACT FROM AUTHOR]

Organo-rectorites (ORts) modified with different quaternary ammonium salts were prepared to remove polar mycotoxin aflatoxin B 1 (AFB 1 ) and weak polar, hydrophobic mycotoxin zearalenone (ZER). The structural and surface properties of the prepared ORts were studied. The intercalation of organic cationic surfactants expanded the interlayer of rectorite and increased the hydrophobicity. In vitro adsorption experiments were carried out to simulate the in vivo conditions of gastrointestinal tract of animals by a batch mode. The prepared ORts showed super enhanced adsorption capacities towards AFB 1 and ZER compared with raw rectorite, indicating the effectiveness of the prepared ORts as mycotoxins adsorbents. The ORts modified with longer chain surfactant molecules possessed a higher adsorption capacity towards mycotoxins. In addition, with increasing the modifier dosage, the adsorption capacity increased first and then decreased. The best adsorption capacity was achieved when the dosage of the modifier increased to 2.0CEC. The adsorption of both AFB 1 and ZER onto ORts could be well described by Langmuir model. In the binary-contaminant system, the existence of AFB 1 would bring negative effect to the adsorption of ZER. On the other hand, the adsorption of ZER was in favor of the adsorption of AFB 1 molecules. The solution pH had negligible influence on the adsorption process of ORts both in single system and binary system, indicating no desorption occurred when the adsorbents pass through from stomach to intestine as animal feed. This study demonstrates that the received ORts could be a promising adsorbent for detoxication of different mycotoxins in real application. [ABSTRACT FROM AUTHOR]

This work aims at exploring the potential of nonionic surfactant octylphenol polyoxyethylene ether (OP-10) modified montmorillonites (NMts) as mycotoxins adsorbent. The resulting NMts has different structural configurations, organic carbon contents, surface hydrophobicity and textural properties at different surfactant loadings. The prepared NMts were used for adsorption of polar aflatoxin B 1 (AFB 1 ) and weak polar zearalenone (ZER) in both single and binary-contaminate systems by simulating conditions of gastrointestinal tract. The adsorption capacities of NMts to AFB 1 and ZER increased up to 2.78 and 8.54 mg/g respectively from 0.51 and 0.00 mg/g of raw montmorillonite (Mt). High adsorption capacities of NMts to AFB 1 and ZER could be reached at low surfactant loadings. There was little decrease from pH of 3.5 to 6.5 but became negligible with increasing the surfactant loadings. In binary-contaminate adsorption system, the adsorption of ZER was obviously affected by the existence of AFB 1 , while ZER had little effect on the adsorption process of AFB 1 due to different adsorption mechanism. This study demonstrates that NMts could be a promising adsorbent for simultaneous detoxification of polar and non-polar mycotoxins. [ABSTRACT FROM AUTHOR]

To overcome rapid electron-hole recombination and low adsorption capacity of single g-C 3 N 4 photocatalyst, the present work reports on the fabrication of two kinds of visible-light-driven composite photocatalysts (g-C 3 N 4 /kaolinite and g-C 3 N 4 /illite composites). 2D/2D assembly was successfully achieved in this work. Furthermore, the as-synthesized composites exhibited significantly enhanced photocatalytic activity under visible-light irradiation, whose reaction rate constants were almost 4.13 times (g-C 3 N 4 /kaolinite) and 3.18 times (g-C 3 N 4 /illite) that of pure g-C 3 N 4 . A plausible reaction mechanism over the as-prepared composite photocatalysts was also proposed based on the experimental results obtained. The photocatalytic enhancement of synthesized composites should be attributed to the intimate interface contact between g-C 3 N 4 and layered minerals, resulting in better dispersion performance, higher charge separation efficiency as well as stronger adsorption ability. [ABSTRACT FROM AUTHOR]

Organo-montmorillonites (OMts) modified with mono- and di-alkyl cationic surfactants were prepared to remove polar mycotoxin aflatoxin B 1 (AFB 1 ) and weak polar, hydrophobic mycotoxin zearalenone (ZER) simultaneously. The structural and surface properties of the prepared OMts were investigated. In vitro adsorption experiments were carried out to simulate the in vivo conditions of gastrointestinal tract of animals by a batch mode. The adsorption of AFB 1 and ZER in both single and binary-contaminate systems were investigated systematically. Both OMts showed super enhanced adsorption capacities towards AFB 1 and ZER whenever in single and binary-contaminate systems compared with raw Mt, indicating the effectiveness of the prepared OMts acted as mycotoxins adsorbents. DODAC-Mt showed a higher adsorption capacity towards AFB 1 and ZER than OTAB-Mt. The equilibrium data of AFB 1 on OMts were fitted satisfactorily with Freundlich and Linear models, suggesting the co-existence of different adsorption mechanism which were proposed to be ion–dipole interactions (between surfactant cations and carbonyl groups of AFB 1 ) and adsorption/partition mechanisms. The adsorption isotherms of OMts to ZER matched best with Linear models, implying the adsorption/partition mechanism. For simultaneous adsorption, the adsorption process of one mycotoxin was slightly affected by the presence of the other mycotoxin due to the requirement of partial same sorption sites. In addition, the solution pH had negligible influence on the adsorption process of OMts, meaning no desorption occurred when the adsorbents pass through from stomach to intestine as animal feed. [ABSTRACT FROM AUTHOR]

A novel 3D heterogeneous g-C 3 N 4 /TiO 2 /kaolinite composite with enhanced visible light activity was fabricated via a mild sol-gel method associated with chemical stripping and self-assembly. Compared with bare photocatalysts, the g-C 3 N 4 /TiO 2 /kaolinite 3D structure exhibits enhanced adsorption-photocatalytic degradation ability for the removal of ciprofloxacin (CIP) under visible-light irradiation, and also facilitate the recyclability of the photocatalyst as demonstrated from the reusability test. The apparent rate constant of the composite is up to around 5.35 times, 6.35 times and 4.49 times that of bare TiO 2 , g-C 3 N 4 and P25, respectively, and a possible degradation pathway was also proposed. On the other hand, the as-received composite also exhibited enriched disinfection ability towards S. aureus . It is indicated that the superoxide radical ( O 2 − ) is the main active species in the degradation process, and the superior photocatalytic performance of composite should be mainly attributed to both the improvement of light harvesting as well as the enhanced separation and transfer efficiency. It is expected that this novel ternary visible-light responding composite would be a promising candidate material for the organic pollutants degradation and bacteria inactivation. [ABSTRACT FROM AUTHOR]

In today's world of antibiotic abuse and bacterial resistance, it is urgent to propose a non-antibiotic solution against bacterial wound infections. Hence, the present work prepared kaolinite (KAO)-based organic antibacterial material (CA/KAO) modified with chlorhexidine acetate (CA) via a dry process. And the potential of CA/KAO in the doping preparation of antibacterial wound dressings was evaluated with poly(vinyl alcohol) (PVA) as an organic matrix. The results demonstrated that a synergistic promotion system between CA and kaolinite was formed. Kaolinite optimized the thermal stability of CA and controlled it to achieve a demand-oriented release mode of "burst + slow" release. CA was mainly attached to the surface of kaolinite by hydrogen bonding to impart its antibacterial properties and enhanced organic compatibility. For Staphylococcus aureus (S. aureus), which is prone to induce wound infections, CA/KAO showed a low-level MIC of 11.72 mg/L and achieved a 98.37% antibacterial rate by contact inactivation and released CA sterilization. CA/KAO was homogeneously dispersed in PVA film and achieved inhibition zones of 15.393 mm and 12.663 mm against S. aureus and Escherichia coli (E. coli) , respectively, at 30 wt% doping. It is expected that CA/KAO would be an option for the mass production of antibacterial wound dressings. [Display omitted] • Chlorhexidine/kaolinite antibacterial material was prepared by a simple dry process. • A synergistic promotion system was formed between chlorhexidine and kaolinite. • Chlorhexidine/kaolinite-doped poly(vinyl alcohol) films prepared by solution-casting method. • Antibacterial material for manufacturing high-quality wound dressings was provided. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel nZVI/kaolinite composite was prepared by liquid-phase reduction method. • nZVI particles with oxide layer were embedded into kaolinite surface and edges. • nZVI/kaolinite exhibits high efficiency for BPA removal with PMS activation. • SO 4 •− and 1O 2 were proved to be the main active components. • The possible degradation pathways were well analyzed and illustrated. Nano-zero valent iron/kaolinite (nZVI/kaolinite) composite was prepared by liquid-phase reduction method in the presence of sodium borohydride. Transmission Electron Microscope images demonstrated that spherical nZVI particles with oxide layer were successfully engaged into the kaolinite surface and edges, which was beneficial to the peroxymonosulfate (PMS) activation and bisphenol A (BPA) degradation. The prepared nZVI/kaolinite composite was endowed with excellent performance in removing BPA with the assistance of PMS, namely more than 95% BPA could be eliminated in 15 min. In contrast with alkaline environment, weak acid and neutral environment were more advantageous to the BPA degradation. All the anions like Cl−, SO 4 2−, HCO 3 − and H 2 PO 4 − were adverse to the BPA degradation in nZVI/kaolinite/PMS system. Furthermore, EPR and radical quenching experiments proved that SO 4 •− and 1O 2 were the main active components during the series reactions. The possible degradation pathways were also inferred based on the liquid chromatography-mass spectrometry (LC-MS) results. Besides, the nZVI/kaolinite composite displayed good performance toward coking wastewater as well. This study is of great significance in designing of efficient persulfate activated materials and treating wastewater. [ABSTRACT FROM AUTHOR]

Based on the urgency of comprehensive utilization of large amount of coal gangue and the demand for the treatment of organic pollution in coal chemical sites and water bodies, novel coal gangue-based persulfate catalytic material (GCM) which can effectively activate peroxymonosulfate (PMS) were prepared by using coal gangue as raw material and adding activator under inert atmosphere. Under the optimized conditions, the degradation rate of GCM-ZnCl 2 material can reach 82.6% in 25min. Among different environmental impact factors, anions have little effect on the degradation rate of phenol, while the initial pH value has a greater impact. When the pH value is 9.0, it belongs to the synergistic effect of alkali activation, and the degradation effect of phenol is relatively better. The GCM-ZnCl 2 material can realize the efficient adsorption of phenol through its large specific surface area and pore volume, and provide more catalytic active sites. The oxygen-containing groups C O (carboxyl, ester, ketone, etc.) on its surface can react with PMS to produce free radical SO 4 •− or induce the production of non-free radical 1O 2 , so as to realize the efficient degradation of phenol. [Display omitted] • Novel coal gangue-based persulfate catalytic materials (GCM) were prepared. • The GCM-ZnCl 2 catalytic material has a large specific area of 141.4 m2/g. • The removal rate of phenol reached 82.6% within 25 min. • Both free radical (.•OH and SO 4 •−) and non-free radical (1O 2) involved in the reaction. • The possible degradation pathways were well analyzed and illustrated. [ABSTRACT FROM AUTHOR]

Diatomite, a porous non-metal mineral, was used as support to prepare TiO 2 /diatomite composites by a modified sol–gel method. The as-prepared composites were calcined at temperatures ranging from 450 to 950 °C. The characterization tests included X-ray powder diffraction (XRD), scanning electron microscopy (SEM) with an energy-dispersive X-ray spectrometer (EDS), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and nitrogen adsorption/desorption measurements. The XRD analysis indicated that the binary mixtures of anatase and rutile exist in the composites. The morphology analysis confirmed the TiO 2 particles were uniformly immobilized on the surface of diatom with a strong interfacial anchoring strength, which leads to few drain of photocatalytic components during practical applications. In further XPS studies of hybrid catalyst, we found the evidence of the presence of Ti–O–Si bond and increased percentage of surface hydroxyl. In addition, the adsorption capacity and photocatalytic activity of synthesized TiO 2 /diatomite composites were evaluated by studying the degradation kinetics of aqueous Rhodamine B under UV-light irradiation. The photocatalytic degradation was found to follow pseudo-first order kinetics according to the Langmuir–Hinshelwood model. The preferable removal efficiency was observed in composites by 750 °C calcination, which is attributed to a relatively appropriate anatase/rutile mixing ratio of 90/10. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel γ-FeOOH/g-C 3 N 4 /kaolinite composite was fabricated via two-step strategy. • Efficient electron transfer induced by γ-FeOOH and N vacancies promote the separation and migration of photo-generated carriers. • γ-FeOOH/g-C 3 N 4 /kaolinite catalyst possessed good bisphenol A removal efficiency. • The potential synergistic enhancement mechanism was well proposed. A novel ternary composite with the flower-like structure was synthesized by integrating of γ-FeOOH and g-C 3 N 4 /kaolinite containing N vacancies (FNGK). The FNGK-10 composite exhibited the superiority of bisphenol A (BPA) degradation in the presence of peroxymonosulfate (PMS) under the visible-light irradiation with the outstanding reusability and universal applicability, in which the degradation rate constant of FNGK-10/PMS/Vis system was about 3.25 and 8.42 times higher than that of FNGK-10/PMS and FNGK-10/Vis system, respectively. Moreover, the introduction of kaolinite leads to the accelerated consumption of PMS. The FTIR, EPR and XPS spectra proved that the formation of Fe-N and cyano (C≡N) bonds induced the enhancement of the efficiency of electron transfer. The photo-generated carriers could be trapped by N vacancies and γ-FeOOH, which was favorable for the separation potency of photoexcited charge carriers and reduction efficiency of Fe(III) to Fe(II). This paper gave a new perspective on the coupling application of PMS activation and photocatalytic technology to efficiently degrade organic contaminants. [ABSTRACT FROM AUTHOR]

Abstract: This study presented a novel method for purification of three different grades of diatomite from China by scrubbing technique using sodium hexametaphosphate (SHMP) as dispersant combined with centrifugation. Effects of pH value and dispersant amount on the grade of purified diatomite were studied and the optimum experimental conditions were obtained. The characterizations of original diatomite and derived products after purification were determined by scanning electron microscopy (SEM), X-ray diffraction (XRD), infrared spectroscopy (IR) and specific surface area analyzer (BET). The results indicated that the pore size distribution, impurity content and bulk density of purified diatomite were improved significantly. The dispersive effect of pH and SHMP on the separation of diatomite from clay minerals was discussed systematically through zeta potential test. Additionally, a possible purification mechanism was proposed in the light of the obtained experimental results. [Copyright &y& Elsevier]

The present work investigated the comparison of the effects of Na2SO3 and Na2SiO3 on thiourea stabilization, and a systematic study was undertaken to establish the effects of these stabilizers on the stability of alkaline thiourea, both qualitatively and quantitatively. The effects of these stabilizers on the activation energy of alkaline thiourea gold leaching was also studied. The results showed that sodium silicate was more suitable as a stabilizer in this system than sodium sulfite because the peak current of gold dissolution with sodium sulfite was higher than that with sodium silicate, but the inhibition of thiourea decomposition by the former was less obvious than that of sodium silicate in the cyclic voltammetry curve. The quartz crystal microbalance results showed that the quality decreased to about 100 ng cm2 in the presence of a stabilizer, while it increased to 300 ng cm2 in the absence of the stabilizer. It is inferred that gold can be dissolved by alkaline thiourea in the presence of a stabilizer, while it cannot without a stabilizer because of the decomposition of thiourea. This assumption was confirmed by atomic force microscopy measurements. The surface activation energy of Au dissolution decreased from 183.76 to 98.07 kJ/moL with the addition of sodium silicate, indicating that Au dissolution was promoted with the chemical. [ABSTRACT FROM AUTHOR]

Binary composite was synthesized via coupling BiOCl with alkali leached natural clinoptilolite (40B0/CN), which showed retarded recombination of photo-generated carriers. The clinoptilolite was pretreated with alkali leaching, resulting in a larger pore size and high cation exchange capacity. The modified clinoptilolite was more feasible for the growth of BiOCl and to promote the adsorption ability for formaldehyde (HCHO). In addition, the cation exchange capacity was conducive to anchor Bi3+, further leading to the reduction of the particle size of BiOCl. The carrier effect of alkali leached natural clinoptilolite promoted the amorphous transformation of BiOCl at low temperature, which simultaneously produced more distortions and defects in the BiOCl lattice. The 40B0/CN composite exhibited the superior light absorption ability with a narrower band gap. The photocatalytic degradation rate for HCHO of 40B0/CN under solar light reached 87.7%, and the reaction rate constant was 0.0166 min−1, which was 1.6 times higher than that of BiOCl. This paper gave a deep insight into photocatalytic technology to efficiently degrade formaldehyde. [ABSTRACT FROM AUTHOR]

Over the past decades, inspired by the outstanding properties of clay minerals such as abundance, low-cost, environmental benignity, high stability, and regularly arranged silica-alumina framework, researchers put much efforts on the interface assembly and surface modification of natural minerals with bare photocatalysts, i.e. TiO 2 , g-C 3 N 4 , ZnO, MoS 2 , etc. The clay-based hybrid photocatalysts have resulted in a rich database for their tailor-designed microstructures, characterizations, and environmental-related applications. Therefore, in this study, we took a brief introduction of three representative minerals, i.e. kaolinite, montmorillonite and rectorite, and discussed their basic merits in photocatalysis applications. After that, we summarized the recent advances in construction of stable visible-light driven photocatalysts based on these minerals. The structure-activity relationships between the properties of clay types, pore structure, distribution/dispersion and light absorption, carrier separation efficiency as well as redox performance were illustrated in detail. Such representative information would provide theoretical basis and scientific support for the application of clay based photocatalysts. Finally, we pointed out the major challenges and future directions at the end of this review. Undoubtedly, control and preparation of novel photocatalysts based on clays will continue to witness many breakthroughs in the arena of solar-driven technologies. [Display omitted] • Kaolinite, montmorillonite and rectorite based photocatalysts were well reviewed. • The role of clay in composite photocatalysts was illustrated in detail. • We point out the major challenges and direction of clay based photocatalysts. • This review is meaningful for energy crisis and environmental remediation. [ABSTRACT FROM AUTHOR]

Developing low-cost, high-efficiency catalysts for advanced oxidation processes remain a key issue for the degradation of organic pollutants. In this study, a novel FeCo 2 O 4 /rectorite composite was synthesized via a facile combustion process and employed to activate peroxymonosulfate (PMS) for dealing with atrazine (ATZ). The addition of rectorite could result in higher specific surface area, smaller pore size and more hydroxyl groups, which were beneficial to enrich pollutants to the adsorption sites and provide sufficient reactive sites. After meticulous evaluation, the degradation efficiency of FeCo 2 O 4 /rectorite composite towards ATZ exhibited improved PMS activation efficiency which was about 2.6 times than that of pure FeCo 2 O 4. Based on the characterization results, the sulfate radicals and hydroxyl radicals were considered to be the main free radicals which were involved into the circulation of Co(II)–Co(III)–Co(II) as well as the oxidation of ≡Fe(II), which was responsible for the remarkable catalytic efficiency. In addition, the chemical stability and superior catalytic performance of FeCo 2 O 4 /rectorite should also be attributed to the chemical combination between metal ions and the surface hydroxyl groups of rectorite. Overall, these findings are beneficial for understanding the mechanism of PMS activation by natural mineral-based catalysts and contributing to the practical application of sulfate-based technology for organic wastewater treatment. Image 1 • In situ growth of FeCo 2 O 4 on natural rectorite for PMS activation was achieved. • FeCo 2 O 4 /rectorite composite exhibited higher PMS activation efficiency than pure FeCo 2 O 4. • Hydroxyl groups of rectorite accelerated PMS activation significantly via combining with metal oxide. • Both OH• and SO 4 •− were identified as main reactive species. [ABSTRACT FROM AUTHOR]

• Carbon doped TiO 2 /kaolinite composite was rationally designed and assembled. • The composite's reaction rate constant is about 25 times higher than that of pure TiO 2. • TiIII defects and localized occupied states are responsible for performance enhancement. • Kaolinite induced carrier effect plays important role in catalytic activity enhancement. • The composite material might be a promising candidate for degrading trace amounts of pollutants. In this work, kaolinite supported monodispersed TiO 2 with carbon regulation was prepared through rational design and different dimensions' assembly, leading to generation of TiIII species in carbon doped TiO 2 /kaolinite (C-TiO 2 /kaolinite) composite. The C-TiO 2 /kaolinite composite exhibited improved degradation performance towards ciprofloxacin under visible light, with a reaction rate constant of 0.00597 min−1, which is about 3.24 and 24.88 times higher than that of 2.0C-T (2.0% carbon-doped TiO 2) and pure TiO 2 , respectively. Based on various materials characterization methods and DFT calculations, it was indicated that the electronic structure was correlated with the changes in light absorption, charge carrier lifetime, and reactive oxygen species (ROS). The enhanced visible light responding ability could be attributed to the synergistic effect between natural kaolinite and nanosized TiO 2 , the formation of localized occupied states in the gap, and the formation of TiIII defects consisted of surface oxygen vacancies. All of them effectively increase the separation efficiency, migration velocity, and lifetime of the photoinduced charge carriers under visible-light irradiation. Overall, our study provides a promising candidate for effective degradation of trace amounts of pharmaceutical and personal care products and other highly toxic contaminants with the assistance of solar light. [ABSTRACT FROM AUTHOR]

A novel CoNi 3 O 4 /diatomite hybrid is constructed through vertically oriented growth of 2D CoNi 3 O 4 nanoribbons with atomic layer-thickness on cost-effective diatomite template. Distinct from stacked CoNi 3 O 4 with a large portion of "dead surface", diatomite derived CoNi 3 O 4 nanoribbons possess abundant exposed edges, sharp corners, and open diffusion channels. These unique characteristics offer CoNi 3 O 4 /diatomite hybrid excellent peroxymonosulfate activation efficiency in real water bodies. • 2D CoNi 3 O 4 nanoribbons were fabricated via vertically oriented growth on diatomite. • CoNi 3 O 4 /diatomite showed rich exposed edges, sharp corners and diffusion channels. • CoNi 3 O 4 /diatomite presented excellent PMS catalytic activity in real water bodies. • S O 4 - • , OH and 1O 2 were generated and functioned in CoNi 3 O 4 /diatomite/PMS system. • O 2 − contributed to reversible redox cycle of Co2+/Co3+ and Ni2+/Ni3+. The reactive oxygen radicals generated by peroxymonosulfate (PMS) activation exhibit great potential to deal with refractory contaminants of emerging concern. However, mass production of efficient and cost-effective catalysts for PMS activation is still a long-term goal for its widespread practical application. Herein, a novel CoNi 3 O 4 /diatomite hybrid is constructed through vertically oriented growth of 2D CoNi 3 O 4 nanoribbons with atomic layer-thickness on cost-effective diatomite template. Distinct from stacked CoNi 3 O 4 , CoNi 3 O 4 /diatomite composite possesses abundant exposed edges, sharp corners, and open diffusion channels. Abundant exposed edges and sharp corners create more open space and active sites for PMS activation. Open diffusion channels accelerate the migration of PMS and contaminants. Such characteristics offer CoNi 3 O 4 /diatomite hybrid excellent PMS activation efficiency. Furthermore, sulfate radical plays the dominant role in atrazine degradation. Superoxide radical contributes to reversible redox cycle of Co2+/Co3+ and Ni2+/Ni3+. This study provides a novel strategy for cost-effective mass production of various Fenton-like 2D catalysts. [ABSTRACT FROM AUTHOR]

• Diatomite and CoFe 2 O 4 was effectively assembled to activate peroxymonosulfate. • CoFe 2 O 4 /diatomite catalyst has lower metal dissolution rate. • Surface structure and crystallization dispersion improve activation performance. • The 1O 2 was the primary active substance for BPA degradation. • Weak basic condition enhanced PMS activation and increased BPA degradation. Porous magnetic CoFe 2 O 4 /diatomite catalyst (CFD) was rationally synthesized via a facile citrate combustion process. The relationship between catalytic performance and material properties of the prepared catalysts was comprehensively investigated by various characterizations, especially for the interface interaction between CoFe 2 O 4 and diatomite as well as crystallization regulation of CoFe 2 O 4. Overall, higher specific surface area, overspreading surface hydroxyl groups, better crystal dispersion and abundant surface-active sites make CFD have better degradation performance of bisphenol A (BPA) than pure CoFe 2 O 4 in the presence of peroxymonosulfate (PMS), and the pseudo-first-order reaction rate constant of 40-CFD (40% CoFe 2 O 4 /diatomite) is almost 5.32 times higher than that of pure CoFe 2 O 4. Besides, CFD has excellent magnetic properties, lower metal dissolution rate and good reusability. In addition, electron paramagnetic resonance (EPR) and radical quenching experiments show that sulfate radicals (SO 4 −) and singlet oxygen radicals (1O 2) generated from the electron transfer of BPA molecule and valence state change of transition metals should be the predominant oxidation species. Moreover, possible degradation pathways of BPA are determined by the detection of intermediates derived from the results of liquid chromatograph–mass spectrometer (LC–MS). In brief, it is indicated that the CoFe 2 O 4 /diatomite composite material is an efficient and environmentally friendly catalyst, which has a great potential application in wastewater treatment by activating PMS. [ABSTRACT FROM AUTHOR]

• Oxygen-vacancy-rich Co 3 O 4 /illite can activate peroxymonosulfate (PMS) efficiently. • Modulating crystallization of Co 3 O 4 by illite resulted in rich oxygen vacancies. • Theoretical calculations were employed to elucidate catalytic mechanism for PMS. • Rich oxygen vacancies accelerated electron-transfer and reduced adsorption energy. • S O 4 - • , OH and 1O 2 were generated and functioned in Co 3 O 4 /illite/PMS system. Natural illite microsheets were firstly utilized to induce oxygen vacancies into ultrafine cobalt oxide (Co 3 O 4) for highly efficient Fenton-like catalysis via activation of peroxymonosulfate (PMS). The results indicated that presence of illite microsheets regulated multi-directional crystallization of Co 3 O 4 nanospheres and resulted in reduced grain size and crystallinity. The smaller grain size provided more reactive edge sites for PMS catalysis. The numerous indistinct lattice boundaries caused by reduced crystallinity created abundant oxygen vacancies. Density functional theory (DFT) calculations illustrated that presence of oxygen vacancies significantly reduced adsorption energy and accelerated electron transfer, which further faciliated PMS activation. The oxygen vacancy-rich Co 3 O 4 /illite exhibited superior catalytic efficiency in real water matrix. Apart from sulfate and hydroxyl radicals, singlet oxygen generated from oxygen vacancy-based reaction pathway also played a significant role in atrazine degradation. This strategy provided a new insight for future designing of natural mineral-based catalysts for efficient wastewater treatment via Fenton-like process. [ABSTRACT FROM AUTHOR]

The increasing cyanobacterial blooms have recently been considered a severe environmental problem. Microcystin-leucine arginine (MC-LR) is one of the secondary products of cyanobacteria metabolism and most harmful cyanotoxins found in water bodies. Studies show MC-LR negatively affects various human organs when exposed to it. The phenotype of the jejunal chronic toxicity induced by MC-LR has not been well described. The aim of this paper was to investigate the effects of MC-LR on the jejunal microstructure and expression level of inflammatory-related factors in jejunum. Mice were treated with different doses (1, 30, 60, 90 and 120 μg/L) of MC-LR for six months. The microstructure and mRNA expression levels of inflammation-related factors in jejunum were analyzed. Results showed that the microstructure of the jejunum was destroyed and expression levels of inflammation-related factors interleukin (IL)-1β, interleukin (IL)-8, tumor necrosis factor alpha, transforming growth factor-β1 and interleukin (IL)-10 were altered at different MC-LR concentrations. To the best of our knowledge, this is the first study that mice were exposed to a high dose of MC-LR for six months. Our data demonstrated MC-LR had the potential to cause intestinal toxicity by destroying the microstructure of the jejunum and inducing an inflammatory response in mice, which provided new insight into understanding the prevention and diagnosis of the intestinal diseases caused by MC-LR. [ABSTRACT FROM AUTHOR]

The low removal efficiency of fine clay impurities in natural powder quartz (NPQ) is the main problem that affects the practical utilization of this natural resource. In this work, detailed characterizations of NPQ and clay impurities in NPQ were analyzed by SEM-EDS, mineral liberation analysis (MLA) and impurities distribution analysis. A combined physical purification process, including sieving, scrubbing and centrifugation, was applied to remove the clay impurities. It was observed that the fine clay impurities adhering on quartz surface were effectively liberated by scrubbing, and the content of Fe2O3 and Al2O3 in the concentrate decreased from 0.48% and 0.40% to less than 0.01% and 0.02% at pH 9.3 or when the dosage of sodium hexametaphosphate (SHMP) was 1 × 103 g/t. The coagulation interaction between quartz and impurities including hematite and orthoclase were analyzed based on the classical Deyaguin-Landau-Verwey-Overbeek (DLVO) theory. The results indicated that the main coagulation affecting the separation efficiency was the heterocoagulation between quartz and impurities and homocoagulation among hematite particles. Furthermore, adding regulators such as sodium hydroxide (NaOH) or SHMP could significantly decrease the zeta potential of minerals and thus increase the total interaction energy (VT), which could effectively improve the dispersion of these fine impurity particles, and consequently improve the removal efficiency of impurities. Reverse increase of the zeta potential of minerals in strongly alkaline solutions or excessive SHMP were detected, which was likely the main factor limiting the further improvement of the purification efficiency. [ABSTRACT FROM AUTHOR]

Zeolite X powder was synthesized using natural low-grade diatomite as the main source of Si but only as a partial source of Al via a simple and green hydrothermal method. The microstructure and surface properties of the obtained samples were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), wavelength dispersive X-ray fluorescence (XRF), calcium ion exchange capacity (CEC), thermogravimetric-differential thermal (TG-DTA) analysis, and N2 adsorption-desorption technique. The influence of various synthesis factors, including aging time and temperature, crystallization time and temperature, Na2O/SiO2 and H2O/Na2O ratio on the CEC of zeolite, were systematically investigated. The as-synthesized zeolite X with binary meso-microporous structure possessed remarkable thermal stability, high calcium ion exchange capacity of 248 mg/g and large surface area of 453 m2/g. In addition, the calcium ion exchange capacity of zeolite X was found to be mainly determined by the crystallization degree. In conclusion, the synthesized zeolite X using diatomite as a cost-effective raw material in this study has great potential for industrial application such as catalyst support and adsorbent. [ABSTRACT FROM AUTHOR]