Rational design of waste anode graphite-derived carbon catalyst to activate peroxymonosulfate for atrazine degradation.

As the rapidly growing number of waste lithium-ion batteries (LIBs), the recycling and reutilization of anode graphite is of increasing interest. Converting waste anode graphite into functional materials may be a sensible option. Herein, a series of carbonaceous catalysts (TG) were successfully prepared using spent anode graphite calcined at various temperatures and applied for activating peroxymonosulfate (PMS) to degrade atrazine (ATZ). The catalyst obtained at 800 °C (TG-800) showed the optimum performance for ATZ removal (99.2% in 6 min). Various experimental conditions were explored to achieve the optimum efficiency of the system. In the TG-800/PMS system, free radicals (e.g., SO4·-, HO·), singlet oxygen (1O2), together with a direct electron transfer pathway all participated in ATZ degradation, and the ketonic (CO) group was proved as the leading catalytic site for PMS activation. The potential degradation routes of ATZ have also been presented. According to the toxicity assessment experiments, the toxicity of the intermediate products decreased. The reusability and universal applicability of the TG-800 were also confirmed. This research not only provides an efficient PMS activator for pollutant degradation, but also offers a meaningful reference for the recovery of waste anode graphite to develop environmentally functional materials.

The diverse roles of halide ions in the degradation of bisphenol A via UV/peracetic acid process at different pH values: Radical chemistry, and transformation pathways.

UV/Peracetic Acid (UV/PAA), as an innovative advanced oxidation process (AOP), is employed to treat bisphenol A (BPA) in water through the generation of hydroxyl radicals (•OH) and carbon-centered radicals (R-C•). The impact of halide ions (Cl-; Br-; I-) on the efficiency of UV/PAA was investigated for the first time under varying pH levels. The presence of halide ions exerted an influence on the reactivity of •OH and R-C•, exhibiting varying degrees of impact across different pH conditions. It was discovered that pH exerts a significant influence on its efficiency, with optimal removal performance observed at a pH 9. The degradation of BPA was inhibited by Cl- through the generation of reactive chlorine species (RCS), which triggers the interconversion between •OH and R-C•. Reactive bromine species (RBS) were produced in the presence of Br-, facilitating BPA degradation and generating HOBr as a supplementary source of •OH radicals. I- primarily generate reactive iodine species (RIS) through photolysis, which facilitates the degradation of BPA. The transformation of BPA involves hydroxylation, demethylation, halogenation, and cleavage reactions to form various products and pathways. The toxicity test demonstrates that the UV/PAA treatment of BPA exhibits lower toxicity, thereby indicating its environmentally friendly.

Linkage Microenvironment of Azoles-Related Covalent Organic Frameworks Precisely Regulates Photocatalytic Generation of Hydrogen Peroxide.

Artificial H2 O2 photosynthesis by covalent organic frameworks (COFs) photocatalysts is promising for wastewater treatment. The effect of linkage chemistry of COFs as functional basis to photoelectrochemical properties and photocatalysis remains a significant challenge. In this study, three kinds of azoles-linked COFs including thiazole-linked TZ-COF, oxazole-linked OZ-COF and imidazole-linked IZ-COF were successfully synthesized. More accessible channels of charge transfer were constructed in TZ-COF via the donor-π-acceptor structure between thiazole linkage and pyrene linker, leading to efficient suppression of photoexcited charge recombination. Density functional theory calculations support the experimental studies, demonstrating that the thiazole linkage is more favorable for the formation of *O2 intermediate in H2 O2 production than that of the oxazole and imidazole linkages. The real active sites in COFs located at the benzene ring fragment between pyrene unit and azole linkage.

Resource utilization of chicken manure to produce biochar for effective removal of levofloxacin hydrochloride through peroxymonosulfate activation: The synergetic function of graphitization and nitrogen functionality.

Transforming hazardous livestock manure into biochar as an advanced oxidation processes catalyst is a two-in-one strategy to treat waste by waste. In this work, a self-modified biochar catalyst obtained from chicken manure is developed for peroxymonosulfate activation to degrade levofloxacin hydrochloride. The deterioration rate of levofloxacin hydrochloride reached 89% in 40 min, after three cycles of the catalyst, the LFX still maintained 52% degradation rate. And under low levofloxacin hydrochloride concentration, the degradation rate can reach 99% within 40 min. Apart from catalyst characterization and optimization, the effects of catalyst, peroxymonosulfate, levofloxacin hydrochloride, co-existing anions, and natural organic matter concentrations during the reaction are investigated. Additionally, the quenching experiments and electron spin resonance spectroscopy both reveal the reaction mechanism. As the graphitic nitrogen combined with the sp2-hybridized carbon in biochar was highly electronegative, thus appealing electrons from neighboring carbon networks, making the adjoining carbon atoms to be positively charged, which facilitated the degradation process. The oxidative degradation of levofloxacin hydrochloride was ascribed to non-radical routes including surface-bound radicals, h+ and 1O2 mediated oxidation, the contribution rates were 91%, 93.5%, and 96.8%, respectively. Moreover, possible degradation pathways of levofloxacin hydrochloride are studied by Density Functional Theory (DFT) and LC-MS analysis. This work provides a novel method to produce chicken manure biochar by self-modified chicken manure during biochar pyrolysis for peroxymonosulfate activation in organic contaminations abatement and reveals the combined effect of graphitization and nitrogen functionalization while providing new ideas for the resource utilization of chicken manure.

Recycling of waste power lithium-ion batteries to prepare nickel/cobalt/manganese-containing catalysts with inter-valence cobalt/manganese synergistic effect for peroxymonosulfate activation.

Developing a high-efficiency peroxymonosulfate (PMS) activator is of great significance for the elimination and mineralization of organic contaminants. Herein, a catalyst (LiNi0.5Co0.2Mn0.3O2, NCM) was constructed using the cathode scrap of spent lithium-ion battery (LIB) for activation of PMS to remove Rhodamine B (RhB). The excellent catalytic capacity of NCM-650 was observed, as RhB was completely removed after 25 min. The NCM-650/PMS process could function effectively over a broad pH scope with favorable reusability and adaptability. The non-radical channels (singlet oxygen and mediated charge transfer) played a dominant role in the removal of RhB. Several reactive radical species (sulfate radicals, hydroxyl radicals and superoxide radicals) also facilitated the degradation of RhB, where the Co2+ and Mn4+ on the surface served as active sites to activate PMS. The synergistic effect of inter-valence cobalt and manganese in the catalyst was the predominant medium during the whole reaction process. According to the intermediates identified by High performance liquid chromatograph-mass spectrometry (HPLC-MS) and the analysis of density function theory (DFT) calculations, N-de-ethylation, chromophore cleavage, ring opening, and mineralization were regarded as the primary decomposition pathways. This research provided a novel perspective on the potential application of waste LIBs for the effective activation of PMS.

Application of functionalized layered double hydroxides for heavy metal removal: A review.

Layered double hydroxides (LDHs) are ionic laminar composites composed of positively charged brucite-like layers with an interlayered region containing charged compensating anions and solvation molecules. Such functional LDHs materials present a strong potential for heavy metal treatment especially for wastewater and soil, due to the large surface area and layered structure. This paper started with the background of techniques for heavy metals treatment and then discussed the potential environmental toxic effects, feasibility, stability of LDH composites. The preparation strategies of LDHs composites, and their application were summarized, followed by main mechanisms involving chelation, complexation, surface precipitation, ion exchange. This work also presented the potential environmental toxic effects, feasibility, stability of LDHs composites, reuse of waste liquid and the ratio adjustment of M2+ and N3+ for LDHs synthesis. While most efforts focused on improving the absorption capacity of LDHs by composites construction, ignoring the toxicity effects and detailed mechanism investigation. Based on a thorough review of the latest development, the challenges and perspectives would be proposed, offering promising insights on environmental purification via LDHs based materials.

Mechanistic insights of removing pollutant in adsorption and advanced oxidation processes by sludge biochar.

With the accelerated industrialization, more and more sewage sludge (SS) needs to be treated properly. The conversion of sludge into harmless biochar material with dual utilization value of adsorption and catalysis by pyrolysis is in line with the concept of sustainable development. However, the reaction mechanisms of pristine sludge biochar (SDBC) and its composites (SDBCs) in adsorption, persulfate (PS), and Fenton-like advanced oxidation processes (AOPs) are very closely related to its adsorption performance and catalytic efficiency. In this paper, from the application mechanisms of SDBC in adsorption and AOPs, we review in detail the common methods for synthesizing SDBC and their characteristics. We discuss the synthesis techniques that affect the structural, chemical, and catalytic properties of SDBC, including gasification, pyrolysis, and hydrothermal carbonation (HTC). The pyrolysis temperature, environmental factors, and sludge characteristics have important effects on the properties of SDBC, leading to different mechanisms in adsorption and catalytic processes. Furthermore, this paper systematically generalizes the mechanisms of SDBCs in adsorption, where π-π interactions and electrostatic attractions are the main adsorption mechanisms. Then, activation mechanisms of SDBCs in PS and Fenton-like AOPs systems are discussed, including free radical pathways and non-free radical pathways. Finally, we present several challenges and perspectives for the application of SDBC and SDBCs in the field of adsorption, PS, and Fenton-like AOPs from the mechanistic point of views.

Adsorption behaviors and mechanisms of Fe/Mg layered double hydroxide loaded on bentonite on Cd (II) and Pb (II) removal.

In this study, FeMg-LDH loaded with bentonite (FeMg-LDH@bentonite) was prepared using the facile co-precipitating method in situ to remove heavy metals from water and then characterized using XRD, SEM, TEM, FTIR, BET, TGA, and XPS. Pb (II) and Cd (II) were selected as the representative heavy metals to evaluate the adsorption capability of the FeMg-LDH@bentonite. The batch adsorption method was adopted to test the effects of the contact time, pH, initial concentration, different cations, and temperatures. The kinetic study indicated that the adsorption of heavy metals onto FeMg-LDH@bentonite was well fitted by the pseudo-second-order method. Isotherms were effectively simulated based on the Langmuir model. The maximal adsorption capability of Cd (II) and Pb (II) can reach 510.2 mg/g and 1397.62 mg/g, exceeding those of conventional adsorbents. The adsorption mechanisms of FeMg-LDH@bentonite demonstrating that there may exist surface complexation, ion exchange, and chemical deposition between FeMg-LDH@bentonite and heavy metals. Moreover, FeMg-LDH@bentonite was found to have a promising application for practically treating wastewater with heavy metals and can be used for various environmental water pollution treatments. The material may be used for heavy metal contaminated soil in the future.

Layered double hydroxides loaded sludge biochar composite for adsorptive removal of benzotriazole and Pb(II) from aqueous solution.

In this work, a novel sludge biochar/Zn-Al layered double hydroxide composite (SL) was synthesized in a facile co-precipitation method, and it was used to simultaneously remove benzotriazole (BTA) and lead ion (Pb(II)). Batch adsorption experiments demonstrated that composites with sludge content of 1.0 g (SL-1.0) had a great adsorption performance for BTA and Pb(II). The maximum adsorption capacities of SL-1.0 for BTA and Pb(II) were 239.6 and 226.1 mg g-1, respectively. There was preferential adsorption of BTA in BTA and Pb(II) binary system. The adsorption mechanism analysis indicated that the BTA and Pb(II) adsorption involved electrostatic attraction and chemical bonding with surface functional groups on SL-1.0. Specifically, hydrogen bonding and π-π interaction were mainly ascribed to BTA adsorption, while complexation with surface function groups dominated Pb(II) adsorption. With the advantages of facile synthesis and excellent adsorption capacity, SL-1.0 possesses great potential for simultaneously removing of BTA and Pb(II) from wastewaters.

Factors affecting HPV infection in U.S. and Beijing females: A modeling study.

Background: Human papillomavirus (HPV) infection is an important carcinogenic infection highly prevalent among many populations. However, independent influencing factors and predictive models for HPV infection in both U.S. and Beijing females are rarely confirmed. In this study, our first objective was to explore the overlapping HPV infection-related factors in U.S. and Beijing females. Secondly, we aimed to develop an R package for identifying the top-performing prediction models and build the predictive models for HPV infection using this R package. Methods: This cross-sectional study used data from the 2009-2016 NHANES (a national population-based study) and the 2019 data on Beijing female union workers from various industries. Prevalence, potential influencing factors, and predictive models for HPV infection in both cohorts were explored. Results: There were 2,259 (NHANES cohort, age: 20-59 years) and 1,593 (Beijing female cohort, age: 20-70 years) participants included in analyses. The HPV infection rate of U.S. NHANES and Beijing females were, respectively 45.73 and 8.22%. The number of male sex partners, marital status, and history of HPV infection were the predominant factors that influenced HPV infection in both NHANES and Beijing female cohorts. However, condom application was not an independent influencing factor for HPV infection in both cohorts. R package Modelbest was established. The nomogram developed based on Modelbest package showed better performance than the nomogram which only included significant factors in multivariate regression analysis. Conclusion: Collectively, despite the widespread availability of HPV vaccines, HPV infection is still prevalent. Compared with condom promotion, avoidance of multiple sexual partners seems to be more effective for preventing HPV infection. Nomograms developed based on Modelbest can provide improved personalized risk assessment for HPV infection. Our R package Modelbest has potential to be a powerful tool for future predictive model studies.

Recent advances in graphitic carbon nitride as a catalyst for heterogeneous Fenton-like reactions.

Graphitic carbon nitride (g-C3N4), an appealing metal-free polymer, has featured in extensive research in heterogeneous Fenton-like reactions owing to its advantages of stable chemical and thermal properties, ease of structural regulation and unique redox ability. However, there are still some gaps in the understanding of the mechanism and fate of g-C3N4 and its derivatives in heterogeneous Fenton reaction degradation of contaminants. This paper gives systematic emphasis to the development and progress of g-C3N4 and its composites as catalysts in heterogeneous Fenton-like reactions. The main synthesis strategies of g-C3N4 composites are discussed, including calcination, hydrothermal method and self-assembly method. Then, the key catalytic properties of g-C3N4 in Fenton-like applications, including anchoring nanoparticles, increasing specific surface area and exposed active surface sites, as well as regulating charge transfer reactions, are highlighted. Special emphasis is placed on its multifunctional role in heterogeneous Fenton-like reactions and the mechanisms involved in the activation of hydrogen peroxide, persulfates, and photocatalytic activation of persulfate. Lastly, the existing challenges and possible development direction of g-C3N4-coupling Fenton reactions are proposed. It is believed that this paper will bring useful information for the development of graphitic carbon nitride in both laboratory studies and practical applications.

Structure-Function Correlations of Carbonaceous Materials for Persulfate-Based Advanced Oxidation.

Carbonaceous materials (CMs), as high-efficiency activators in a persulfate-based advanced oxidation process (PS-AOP), are attracting increasing attention for environmental remediation due to their high efficiency, low toxicity, and environmental friendliness. The correlations between the structural and surface properties of carbonaceous materials and the catalytic reaction efficiency in PS-AOP have been focused on experimentally and theoretically. In this Perspective, we discuss the effect of the microstructure of carbonaceous materials on the catalytic reaction efficiency, which can depend on the reaction pathways, including adsorption, free-radical routines, and non-free-radical pathways. Various features of carbonaceous materials, covering the dimensionality, pristine carbon configuration, crystallinity, defects, porosity, chemically active groups, and heterogeneous doping, can be involved. Those characteristics mainly affect the electronic process and mass transfer during the whole PS-AOP. An important target in the field is how to rationally regulate the intrinsic properties of carbonaceous substances to control both the reaction pathways and catalytic efficiency. Therefore, we conclude with a critical discussion and presentation of future challenges.

Recovery of CuO/C catalyst from spent anode material in battery to activate peroxymonosulfate for refractory organic contaminants degradation.

It is critical to developing low-cost and efficient catalysts to activate peroxymonosulfate for the degradation of organic contaminants, whereas it remains challenging. In the study, a recycle method to synthesize efficient heterogeneous catalysts was developed by exploiting the anode electrode of spent lithium-ion batteries as the raw material based on a one-step calcination process. The recycled anode material (AM) composed of copper oxide and graphite carbon was capable of efficiently activating peroxymonosulfate (PMS) to degrade a wide range of organic contaminants. In addition, an investigation was conducted on the effect of reactive parameters (e.g., catalyst dose, PMS dose, RhB concentration, and coexisting matters). Besides, the AM/PMS process could exhibit high effectiveness at a broad pH range (3-10) and in a real water matrix. The redox cycle of Cu(II)/Cu(I) in the AM acted as the predominated force to effectively facilitate the PMS activation for the formation of oxygen species, in which the SO4·- and 1O2 exerted a primary effect. Moreover, the non-radical pathway of electron transfer between RhB and PMS facilitated the removal of RhB. In this study, a reclamation approach was developed for the recycling of spent LIBs anodes, and insights into the development of catalysts in SR-AOPs were gained.

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.

[Response surface methodology for optimizing the technology of induction and isolation of dendritic cells by multiple cytokines].

Objective To promote the induction and separation efficiency of bone marrow-derived dendritic cells (BMDCs) in vitro through optimizing the inducing and isolating process by multiple cytokines. Methods The factors to be optimized in single factor tests included recombinant mouse granulocyte macrophage-colony stimulating factor (rmGM-CSF), recombinant mouse interleukine 4 (rmIL-4), lipopolysaccharide (LPS), recombinant mouse tumor necrosis factor α (rmTNF-α) and inducing time. The numbers of immature dendritic cells (imDCs) and mature dendritic cells (mDCs) were investigated as the indicators. Box-Behnken experimental design-response surface methodology was used to analyze and verify the data. Morphological changes were observed using the inverted microscopy and the transmission electron microscopy. Surface molecules including CD11c and CD86 were detected using the flow cytometry. Results The optimum inducing conditions for imDCs were obtained as follows: rmGM-CSF was 46 ng/mL, rmIL-4 was 24 ng/mL, inducing time was 6 days, and the number of imDCs was (4.58±0.28)×106 cells, and the relative deviation was 4.00%. The optimum inducing conditions for mDCs were as follows: LPS was 1.4 µg/mL, rmTNF-α was 30 ng/mL, inducing time was 1 day, and the number of mDCs was (4.21±0.15)×106 cells, and the relative deviation was 3.80%. Sufficient typical imDCs and mDCs were obtained within 5-7 days of induction in vitro. Also, flow cytometry showed that the amplified imDCs had a high expression of CD11c (68.62%±2.3%) and a low expression of CD86 (37.95%±1.8%), and the mDCs had high expressions of both CD86 (90.34%±1.4%) and CD11c (82.05%±1.6%). Conclusion The combination of single factor tests and Box-Behnken design -response surface methodology could optimize the inducing and isolating method for DCs in vitro by multiple cytokines rapidly and efficiently, which provided basic experiment materials for further studies.