Article
Engineering, Environmental
Jinyu Gao, Zekun Liu, Michael J. Bentel, Yaochun Yu, Yujie Men, Jinyong Liu
Summary: The direct linkage in Ω-HPFCAs enables easier degradation under UV/sulfite treatment compared to PFCAs, while the presence of the H atom makes Ω-HPFCAs more susceptible to decarboxylation but less susceptible to hydrodefluorination than PFCAs. Experimental results showed that Ω-HPFCAs only yield shorter-chain products during transformation, rather than longer-chain PFCAs.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2021)
Article
Engineering, Environmental
Dongbao Song, Biting Qiao, Xin Wang, Leicheng Zhao, Xiao Li, Peng Zhang, Yiming Yao, Hao Chen, Lingyan Zhu, Hongwen Sun
Summary: This study provides new insight into the degradation of PFOA by an electrochemical system in the presence of reactive chlorine species (RCS) and distinguishes the roles played by reactive chlorine species and hydroxyl radical. By using electrochemical oxidation in the presence of NaCl, PFOA degradation rates of 89.4%-94.9% and defluorination rates of 38.7%-44.1% were achieved after 480 min. The study revealed that the degradation occurred via the synergistic effect of hydroxyl radical and reactive chlorine species rather than through direct anodic oxidation. The findings are promising for the development of electrochemical technology to remove perfluorinated alkyl substances from the environment.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Environmental Sciences
Hannah Milh, Xingyue Yu, Deirdre Cabooter, Raf Dewil
Summary: In this study, the efficiency of UV-based sulfate radical advanced oxidation processes (SR-AOP) and UV-based advanced reduction processes (ARP) in degrading ciprofloxacin (CIP) in wastewater was investigated. It was found that the UV/PS process was more efficient than the UV/PMS process in SR-AOPs, while the UV/sulfite process was the most efficient among ARPs. The optimal process parameters and the contribution of different reactive species were determined for each process.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Environmental Sciences
Brian P. DiMento, Cristina L. Tusei, Christoph Aeppli
Summary: Short-chain chlorinated paraffins (SCCPs) are persistent organic pollutants. This study evaluated the potential for photochemically-produced hydrated electrons (e((aq))(-)) and hydroxyl radicals ((OH)-O-center dot) to degrade SCCPs. The results showed that SCCPs can be degraded by both e((aq))(-) and (OH)-O-center dot, with higher chlorine content leading to higher rate constants for e((aq))(-).
Article
Engineering, Environmental
Sohag Biswas, Sharma S. R. K. C. Yamijala, Bryan M. Wong
Summary: Per- and polyfluoroalkyl substances (PFASs) are synthetic contaminants found in drinking water and consumer products. In this study, we use ab initio molecular dynamics simulations to investigate the degradation of PFASs using hydrated electrons. The results show that the mechanism of PFAS degradation with hydrated electrons is different from that with excess electrons/charges, which has been commonly used in previous computational studies. The activation barriers for PFAS degradation are relatively low, but diffusion-limited.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2022)
Article
Engineering, Environmental
Huimei Pan, Yuanxi Huang, Juan Li, Boqiang Li, Yang Yang, Baiyang Chen, Rongshu Zhu
Summary: This study investigated a green, chemical-free technology using ultraviolet/vacuum ultraviolet (UV/VUV) to degrade haloacetaldehydes (HALs) in drinking water. The results showed that UV/VUV irradiation significantly enhanced the degradation of HALs compared to UV irradiation alone, with VUV playing a key role in the degradation process. The study also revealed the presence of both oxidation and reduction reactions during the VUV process. Photooxidation mineralized HALs, while photoreduction dehalogenated HALs and produced intermediate organic compounds. The pH and dissolved oxygen levels affected the overall photodegradation rates.
Review
Environmental Sciences
Qingya Fan, Lingli Wang, Yu Fu, Qingchao Li, Yunjiao Liu, Zhaohui Wang, Huaiyong Zhu
Summary: The redox cycling of iron (III)/iron (II) in clay minerals plays an important role in the biogeochemical cycles of nutrients and the behavior of environmental contaminants. Different types of iron in clay minerals exhibit distinct reactivity towards contaminants. This review summarizes recent discoveries on the redox reactivity of iron in clay minerals and its links to the fate of environmental contaminants.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Environmental Sciences
Mengxi Tan, Shaochong Liu, Ning Chen, Yuliang Li, Liqiang Ge, Changyin Zhu, Dongmei Zhou
Summary: The role of iron phases in preserving organic carbon can be reversed under redox-fluctuation conditions, especially for Fe(II) minerals-protected organic carbon. Hydroxyl radicals produced during oxidation processes can induce mineralization of organic carbon associated with Fe(II) minerals.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Environmental Sciences
Lei Tian, Shan-Shan Liu, Xun-Heng Jiang, Li-Sha Chen, Shao-Lin Wu, Wen-Jun Xiao, Jie-Ping Fan, Dai-She Wu, Jian-Ping Zou
Summary: This study investigates the selective oxidation capacity of coexisting SO4 center dot(-) and center dot OH towards organic moieties with differing electronegativity, shedding light on the degradation pathways of an organic contaminant.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Engineering, Environmental
Jinxing Zhang, Zhaoyu Zhou, Zhiyuan Feng, Hongying Zhao, Guohua Zhao
Summary: This study proposes a strategy for the fast generation of hydroxyl radicals through rerouting the electron transfer pathway. By modifying F-TiO2, the electrocatalytic reduction of oxygen to H2O2 with high selectivity is achieved, and an additional channel facilitates the generation of hydroxyl radicals. The proposed method shows fast kinetics for removing organic pollutants in wastewater treatment, and the degradation efficiency is less affected by the water source and pH value.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2022)
Article
Engineering, Environmental
Yixin Huang, Jing Zou, Jinbin Lin, Haoyu Yang, Mengyun Wang, Jiawen Li, Wei Cao, Baoling Yuan, Jun Ma
Summary: This study discovers that 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS) can serve as both an activator and an electron shuttle to enhance the activation of peroxydisulfate (PDS) and enhance the degradation of diclofenac (DCF). The PDS/ABTS system generates multiple reactive species, with ABTS(center dot+) and (OH)-O-center dot directly contributing to the degradation of DCF. The PDS/ABTS system shows good anti-interference capacity and further improved performance can be achieved by encapsulating ABTS into cellulose.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2022)
Article
Environmental Sciences
Shuo Li, Yalun Yang, Heshan Zheng, Yongjie Zheng, Tao Jing, Jun Ma, Jun Nan, Yoong Kit Leong, Jo-Shu Chang
Summary: This paper summarizes the recent findings on advanced oxidation processes (AOPs) for landfill leachate treatment, focusing on the production routes and mechanisms of hydroxyl radical (·OH) and sulfate radical (SO4·-). It also highlights the challenges of using a single advanced oxidation technology for treating special leachates and the potential of synergistic combination with biological or physical methods.
Article
Environmental Sciences
Yunping Tong, Xinghao Wang, Zhaoyue Sun, Juan Gao
Summary: The study found that AP transformation mediated by Fe3+ saturated clay particles can remove a high percentage of AP within a limited time, and highlighted the significant effects of dissolved oxygen concentration and light conditions on AP removal. The results revealed that AP radicals can form dimers under dark condition, while oxidation products can be generated under light conditions.
Article
Environmental Sciences
Yijin Yuan, Lizhen Feng, Xianqin He, Mengsi Wu, Zhihui Ai, Lizhi Zhang, Jingming Gong
Summary: This study explored the significantly accelerated defluorination of recalcitrant perfluorooctanoic acid (PFOA) with the co-present nitrate by UV/sulfite treatment. The deep defluorination of PFOA and complete denitrification of nitrate were simultaneously achieved in the UV/sulfite-nitrate system. It was found that reactive nitrogen species (RNS) played significant roles in the promoted defluorination apart from reductive defluorination. The results highlight the importance of the UV/sulfite-nitrate system for the remediation of perfluorinated compound contaminated water.
ENVIRONMENTAL POLLUTION
(2022)
Review
Environmental Sciences
Huiling Xia, Chengwei Li, Guoying Yang, Zhiang Shi, Chenxi Jin, Wenzhi He, Jingcheng Xu, Guangming Li
Summary: This paper provides a detailed classification and comprehensive review of microwave-assisted advanced oxidation processes (MW-AOPs) in wastewater treatment. The latest applications of microwave in different advanced oxidation systems are discussed, along with the discussion of reaction parameters, performance, and operating costs of MW-AOPs. Recommendations for future research on MW-AOPs are also provided, highlighting the potential development and evolution of this technology.
Article
Engineering, Environmental
Yaochun Yu, Shun Che, Changxu Ren, Bosen Jin, Zhenyu Tian, Jinyong Liu, Yujie Men
Summary: The recently discovered microbial reductive defluorination provides valuable insights into the environmental fate of PFASs and potential bioremediation strategies. This study systematically investigates the role of C=C double bonds in the biodegradability of unsaturated PFASs. The results show that alpha,beta-unsaturation is crucial for FCA biotransformation, and specific unsaturated FCA structures with trifluoromethyl branches exhibit enhanced degradability and defluorination capability.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2022)
Article
Engineering, Environmental
Zekun Liu, Zhanghao Chen, Jinyu Gao, Yaochun Yu, Yujie Men, Cheng Gu, Jinyong Liu
Summary: The addition of iodide in the UV/sulfite system significantly accelerates the degradation of PFAS, improves reaction rates and removal efficiency, and enhances utilization of sulfite.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2022)
Article
Engineering, Chemical
Xuesong Ye, Jun Nan, Zhencheng Ge, Qiliang Xiao, Bohan Liu, Yujie Men, Jinyong Liu
Summary: This study systematically compared the performance of pristine and MnO2-preloaded ultrafiltration membranes in removing ferrous iron, manganese, and ammonia from source water. The results showed that the MnO2-preloaded membrane not only allowed higher water flux but also exhibited better removal efficiency for these contaminants. Additionally, higher ammonia concentration resulted in a thicker bio-cake layer, leading to higher pollutant removal efficiency and a decrease in stable flux.
JOURNAL OF MEMBRANE SCIENCE
(2022)
Article
Engineering, Environmental
Jinyu Gao, Qiang Zhao, Cheng Tan, Shaohua Xie, Yadong Yin, Fudong Liu, Haizhou Liu, Baoliang Chen, Jinyong Liu
Summary: Adding CrIII or AlIII salts to PGM catalysts in water suspension can greatly accelerate the reduction of oxyanion pollutants. The addition of K2CrVIO4, K2CrVI2O7, or KCrIII(SO4)2 to Pd/C enhances the reduction of BrO3- by 6-fold. The immobilization of reduced CrVIas CrIII(OH)3 on the catalyst surface increases the adsorption equilibrium constant for BrO3- onto Pd/C by 37-fold.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Review
Engineering, Environmental
Jinyong Liu, Jinyu Gao
Summary: This paper discusses the advances, challenges, and opportunities for the research of catalytic reduction of water pollutants. It presents case studies on the development of palladium-based catalysts for the reduction of nitrate, chlorate, and perchlorate. The paper emphasizes the importance of screening and designing catalytic metal sites to achieve new functionalities. It also highlights the convenient catalyst preparation approach and discusses directions that are not immediately necessary or desirable in catalyst research. Finally, it recommends future catalyst development in both fundamental and applied aspects to benefit environmental protection.
FRONTIERS OF ENVIRONMENTAL SCIENCE & ENGINEERING
(2023)
Article
Nanoscience & Nanotechnology
Michael J. Bentel, Marc M. Mason, Ezra L. Cates
Summary: This study investigates the crystallization of synthetic BOHP microparticles through hydrothermal synthesis and examines the influence of different hydroxide amendments and inorganic metal cations on the crystal structure and morphology. The catalytic activity of BOHP in the ultraviolet photocatalytic destruction of PFOA is found to be influenced by the choice of reagents and their effect on crystal defects and surface facet growth.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Engineering, Environmental
Mengqiao Li, David P. Durkin, Gordon Waller, Yaochun Yu, Yujie Men, Tao Ye, Hanning Chen, Danmeng Shuai
Summary: In this study, we evaluated the stability, aging, and environmental impact of g-C3N4 nanosheets under the attack of free chlorine and reactive chlorine species (RCS). We found that g-C3N4 nanosheets were slowly oxidized by free chlorine, but decomposed rapidly when ClO· and/or Cl2·- were the key oxidants. Our study highlighted the high electrophilic attack efficacy of Cl2·- and ClO· on g-C3N4 nanosheets, compared to previous studies. Additionally, a trace level of covalently bonded Cl was introduced to g-C3N4 nanosheets after free chlorine and RCS oxidation. This study provides insights into the environmental fate and transformation of g-C3N4 nanosheets and guides the design of reactive, robust, and safe nanomaterials for engineering applications.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Engineering, Environmental
Ping Han, Ana B. Rios-Miguel, Xiufeng Tang, Yaochun Yu, Li-Jun Zhou, Lijun Hou, Min Liu, Dongyao Sun, Mike S. M. Jetten, Cornelia U. Welte, Yujie Men, Sebastian Lucker
Summary: This study investigated the metabolic capacity of comammox Nitrospira inopinata and Nitrospira kreftii to transform benzimidazole fungicides. The comammox bacteria were found to actively transform all the tested fungicides, except for thiabendazole. The identified transformation products suggested hydroxylation, S-oxidation, and glycosylation as the major biotransformation pathways.
JOURNAL OF HAZARDOUS MATERIALS
(2023)
Review
Engineering, Environmental
Jiaxin Zhu, Zekun Liu, Yihua Chen, Zhiqiang Chen, Hang Ma, Jian Sun, Liao Meng, Tongzhou Liu
Summary: The discharge of widely used fluorinated aromatics (FAs) leads to their notoriously high persistence and toxicity in natural environments. Defluorination is the key step for FAs pollutants detoxification. In this study, 4-fluorophenol (4-FP) was selected as a model compound to optimize the electrochemical hydrodefluorination (HDF) process and understand the reaction mechanism. The investigation showed that Rh coating outperformed Pd coating due to its higher reactivity towards C-F bond cleavage.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Environmental
Bosen Jin, Yiwen Zhu, Weiyang Zhao, Zekun Liu, Shun Che, Kunpeng Chen, Ying-Hsuan Lin, Jinyong Liu, Yujie Men
Summary: This study investigated the structure-biodegradability relationship for different ether PFAS in activated sludge communities. Only polyfluorinated ethers with specific molecular structures underwent biotransformation, leading to the formation of unstable fluoroalcohol intermediates subject to spontaneous defluorination. The findings suggest that aerobic biotransformation/defluorination can complement advanced reduction processes for cost-effective treatment of PFAS.
ENVIRONMENTAL SCIENCE & TECHNOLOGY LETTERS
(2023)
Article
Engineering, Environmental
Jinyu Gao, Gongde Chen, Qi Fu, Changxu Ren, Cheng Tan, Haizhou Liu, Yin Wang, Jinyong Liu
Summary: This study demonstrates an 18-fold activity enhancement in the catalytic reduction of chlorate by integrating vanadium into the palladium catalyst. X-ray photoelectron spectroscopy and electrochemical studies provide insights into the reaction mechanism.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Engineering, Environmental
Changxu Ren, Eric Y. Bi, Jinyu Gao, Jinyong Liu
Summary: We have developed a highly active ligand-enabled Mo-Pd/C catalyst for the reduction of aqueous perchlorate (ClO4-) using hydrogen gas. This catalyst exhibits satisfactory properties for the treatment of ClO4- in waste brines, even in the presence of concentrated salts and humic acid. It shows promise as a competitive alternative to microbial reactors for ClO4- reduction.
ACS ES&T ENGINEERING
(2022)