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Introduction: Volatile organic compounds (VOCs) have attracted widespread attention due to their adverse effects on human health. Photocatalytic oxidation is an effective technology for degrading VOCs under ambient conditions. Methods: In order to better understand the trends and development of global trends in photocatalytic oxidation of VOCs, the analysis of 2493 articles or reviews from the Science Citation Index Expanded (SCIE) in the Web of Science Core Collection, covering the period from 1998 to 2023, was conducted using CiteSpace and VOSviewer software. Results and Discussion: The findings indicate significant growth in papers concerning photocatalytic oxidation of VOCs. China emerges as the most active country among the main drivers. Principal sources publishing relevant research are Applied Catalysis B-Environmental, Chemical Engineering Journal, Journal of Hazardous Materials, and Environmental Science and Technology. A relatively well-established theoretical framework has been developed for the study of photocatalytic oxidation of VOCs. In the field of VOCs photocatalytic oxidation, the focus is on the development and optimization of advanced photocatalysts with efficient charge separation, better adsorption performance, and a wider light response range. In addition, the in-depth study of the charge generation and transfer mechanisms within the photocatalysts, as well as the comprehensive understanding of the reaction kinetics and catalytic oxidation process, the optimization of the reaction conditions, and the improvement of the catalytic efficiency are at the forefront of the research in this field. This research system is advancing and becoming more refined, with its theoretical propositions, research findings, and methodologies increasingly employed and confirmed. [ABSTRACT FROM AUTHOR]

In the present study, a combined process of microwave-assisted chlorination roasting-water leaching was developed to efficiently extract metal ions from spent ternary lithium-ion batteries. Polyvinyl chloride (PVC) was used as chlorine source to generate HCl for chlorination reaction. Activated carbon was first selected as the optimal absorbing medium material. Subsequently, spent anode graphite was used to induce carbonisation reduction reaction with spent LiNixCoyMnzO2 (NCM) to promote recovery of valuable metals. The characterisations of X-Ray Diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM) and thermodynamic analysis indicated that HCl derived from PVC pyrolysis could spontaneously react with carbonisation reduction products from spent NCM to form the corresponding water-soluble metal chloride for the effective recovery of valuable metals. Under the optimal conditions with reaction temperature at 450°C, material mass ratio PVC:NCM of 4:1, reaction time at 60 min and microwave power at 500 W, 96.43% of Li, 95.51% of Ni, 95.27% of Co and 95.43% of Mn can be recovered, respectively. The leaching kinetics can be described by the Avrami equation with surface chemical reaction controlled, and the leaching activation energies of Li, Ni, Co and Mn were 36.32, 42.31, 38.84 and 41.96 kJ∙mol−1, respectively. This microwave-assisted method might provide a new route for the effective recycling of spent lithium-ion batteries by chlorinated metallurgical processes. [ABSTRACT FROM AUTHOR]

Degradation efficiency of 4-bromo-2-chlorophenol (BCP) containing both chlorine and bromine substituents in Co/PMS process was investigated in the light of a wide range of substrate, oxidant, catalyst concentrations and pH value. The effects of chloride ion (Cl−) on degradation kinetics, total organic carbon (TOC) removal and intermediates formation during BCP depletion in Co/PMS system were studied. The kinetics results demonstrated that the dual effect of Cl− on BCP depletion in Co/PMS system due to different mechanisms involved. High concentrations of Cl− (>5 mM) can significantly promote the degradation of BCP, but did inhibit BCP mineralisation to a certain extent which was closely related to Cl− content. High degradation rates but lower mineralisation rates were found in the laboratory experiments, owing to the fact that BCP was mainly transformed to new halogenated intermediates instead of complete mineralisation. Gas chromatograph-mass spectrometer (GC-MS) data verified that a series of chlorinated by-products were formed during BCP decomposition process involving of the participation of Cl−. The proposed degradation pathways of BCP and its derivatives in presence of Cl− were discussed on the basis of intermediate products including the undesirable halogenated by-products recognised by GC-MS. These results might offer some new perspectives on the transformation fates of BCP by utilising Co/PMS regent. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the efficacy of acupuncture in the treatment of pressure ulcers. Randomized controlled trials evaluating the effects of acupuncture on pressure ulcers were identified through a comprehensive literature search on public database. The quality assessment of the included trials was performed based on the guidance of the Cochrane Reviewers' Handbook, and pooled analyses were performed by using the RevMan 5.4 software. The pooled results demonstrated that acupuncture in combination with standard wound care was significantly superior to standard wound care alone with regard to effective rate (RR 1.17, 95% CI [1.10, 1.24]), reduction in Wound Size (MD −2.78, 95% CI [−2.43, −1.44]), healing time (MD −6.24, 95% CI [−12.32, −0.17]) and the amount of 24‐h exudate (MD −0.86, 95% CI [−1.54, −0.18]). In conclusion, this study suggests that acupuncture can be used as an adjunctive therapy to promote healing of pressure ulcers. [ABSTRACT FROM AUTHOR]

The removal of decabromodiphenyl ether (BDE 209), as a typical persistent organic pollutant (POP), is of worldwide concern. Mechanochemical (MC) processes are promising methods to degrade environmental pollutants, most of which use a single grinding reagent. The performance of MC processes with co-milling agents still needs to be further verified. In this study, an efficient MC treatment with combined utilization of lithium cobalt oxide (LiCoO2) and iron (Fe) as co-milling reagents for BDE 209 degradation was investigated. The synchronous action of LiCoO2 and Fe with a LiCoO2/Fe/Br molar ratio of 1.5:1.67:1 and a ball-to-powder ratio of 100:1 led to almost thorough-paced abatement and debromination of BDE 209 within 180 min using a ball milling rotation speed of 600 rpm. The reduction in particle sizes and the destruction of crystal structure in mixture powders with the increase in milling time induced the enhanced degradation of BDE 209, as characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The X-ray photoelectron spectroscopy (XPS) characterization showed that the valence state of Co was converted from Co(III) to Co(II), and Fe(0) was changed to Fe(III) when treated with an MC process. This indicated that the reductive debromination of BDE 209 by Fe and the following oxidative degradation of debrominated products by LiCoO2 were integrated in a concerted way. It proved the removal of BDE 209 via an MC treatment. The full breakage of C-Br and C-O bonds in BDE 209 was confirmed by Fourier transform-infrared spectrometry (FT-IR) spectra, and a possible abatement pathway was also proposed based on the identified intermediate products using gas chromatography–mass spectrometry (GC-MS). These obtained results indicated that a combination of LiCoO2 and Fe as co-milling reagents is promising in the MC treatment of toxic halogenated pollutants like BDE 209. [ABSTRACT FROM AUTHOR]

An efficient sequential mechanochemical activation and complexation leaching for enhanced recovery of valuable metals from spent lithium-ion batteries was explored. The cathode material of lithium cobalt oxide (LiCoO2) was firstly ground in a planetary ball mill, and then diluted into an ethylene diamine tetraacetic acid (EDTA) and hydrogen peroxide (H2O2) leaching solution. One hundred percent of cobalt (Co) and 98.2% of lithium (Li) could be leached from the activated LiCoO2 materials compared with the non-activated (the leaching efficiencies of 7.9% for Co and 4.1% for Li), indicating that the mechanochemical activation process could significantly improve the EDTA/H2O2 mixed liquor complexation leaching of valuable metals from spent LIBs. The involved kinetics and mechanism were explored by carrying out characterization and theoretical calculations. Results demonstrated that an exponential kinetic model could well describe the mechanochemical process, and the Avrami equation leaching model provided a satisfactory fitting relevant for the subsequent improved leaching process. The breakage of the layer structure, the Co–O-Co unit, and the LiCoO2 surface, along with a decrease in activation energy, resulted in the enhancement of the leaching efficiency following mechanochemical activation. Enhanced leaching of Co was owing to the reduction of Co(III) to Co(II) instantaneously forming Co(II)-EDTA chelates. The acidity of EDTA and H2O2 promoted upgrade dissolution of lithium after mechanochemical activation for LiCoO2. This efficient and benign recovery process is of great significance for recycling spent LIBs. [ABSTRACT FROM AUTHOR]