ENVIRONMENT INTERNATIONAL
·
2019
·
IF 7.943
Shibin Liu,Shengyan Pu,Daili Deng,Hongyan Huang,Chun Yan,Hui Ma,Bahar S. Razavi
Chromium (Cr) contamination is especially hazardous to soil biota. Application of manure and biochar has been frequently proposed to remediate Cr-contaminated soil. However, the understanding of mechanisms behind manure and biochar impacts on soil enzyme activities requires advanced visualization technologies. For the first time, we compared manure and its biochar influence on the spatial distribution of β-glucosidase, N-acetyl-glucosaminidase and phosphomonoesterase activities in Cr-contaminated soil using direct zymography. Maize was planted for 45 days in (a) soil mixed with manure, (b) soil mixed with manure-derived biochar and (c) soil without any addition. Soil pH decreased over 45 days, inducing an increase in acid soluble Cr. The concomitant decrease in β-glucosidase and N-acetyl-glucosaminidase activities explained the narrowing rhizosphere extent of enzyme activities by 13–44%, indicating that increased Cr bioavailability decreases microbial activities. A larger maize performance index and the greatest plant shoot/root ratio after biochar application suggested enhanced maize growth ( p < 0.05). In contrast, manure induced the narrowest extent of β-glucosidase and phosphomonoesterase activities due to the addition of labile organic compounds and nutrients following its application. Our study emphasizes the importance of pH on Cr bioavailability and enzyme activities and demonstrates that biochar application is more ideally suited for remediating Cr-contaminated soil.
研究领域:
环境科学
·
微生物学
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2012
·
IF 3.461
Xiuqi Qiu,Zhanqiang Fang,Xiaomin Yan,Wen Cheng,Kairong Lin
Nanoscale zero-valent iron (nZVI) technology is promising for treating the oxidizing pollutants. Understanding the potential risk of nZVI in solution is important for in situ remediation. In this work, the impacts of nZVI on the chemical properties of solution and microorganism were investigated to assess the risk of environmental exposure of nZVI. The effects of salinity (NaCl), pH and humic acid on the chemical stability of nZVI were studied, the concentrations of released toxic ions within 36 days were examined, and the toxicity of solution was evaluated based on the luminous bacteria-based toxicity test. The results indicated that nZVI was chemically stable as the total chromium concentration was below 0.05 mg/L all along and the maximum concentration of released total iron ion was 0.22 mg/L. The results of the toxicity test showed that the reaction products were non-toxic to microorganism even if they existed in solution for a long-term time.
研究领域:
环境科学
·
毒理学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL POLLUTION
·
2024
·
IF 7.6
Zhanbin Luo,Xuyue Pan,Yi Xia,Xueying Duan,Jing Ma,Fu Chen
Due to the rapid increase in industrial and urban areas, environmental pollution is increasing worldwide, which is causing unwanted changes in air, water, and soil at biological, physical, as well as chemical levels that ultimately causing the negative effects in living things because of toxic level of chromium (Cr). However, nanotechnology is capturing great interest worldwide due to their stirring applications in various fields. For this purpose, a pot experiment was conducted to examine plant growth and exo-physiology in rice ( Oryza sativa L.) under the different levels of wastewater 50% and 100% concentrations which were also primed with three nanoparticles (NPs)—copper oxide (nCuO), silicon (nSi), and zinc oxide (nZnO). The research outcomes indicated that elevated levels of wastewater in the soil (100%) notably reduced plant growth and biomass, photosynthetic pigments, and gas exchange attributes. However, increasing levels of Cr stress also induced oxidative stress in the plants by increasing malondialdehyde (MDA), hydrogen peroxide (H 2 O 2 ), which also induced increased compounds of various enzymatic and non-enzymatic antioxidants and also the gene expression and sugar content. Furthermore, a significant increase in proline metabolism, the AsA–GSH cycle, and the pigmentation of cellular components was observed. Although, the application of nCuO, nSi, nZnO–NPs showed a significant increase in plant growth and biomass, gas exchange characteristics, enzymatic and non-enzymatic compounds, and their gene expression and also decreased oxidative stress. In addition, the application of nCuO, nSi, nZnO–NPs enhanced cellular fractionation and decreased the proline metabolism and AsA−GSH cycle in O. sativa plants. These results open new insights for sustainable agriculture practices and hold immense promise in addressing the pressing challenges of heavy metal contamination in agricultural soils.
研究领域:
环境科学
·
农业科学
·
分子生物学
✓ 已验证
DOI
PubMed
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2019
·
IF 3.375
Changjun Liu,Yingming Zhu,Kequan Mu,Qiang Liu,Hairong Yue,Wei Jiang
This work presents a strategy to convert the Cr(VI) pollutant in wastewater into active Cr catalysts in one step by simultaneous photoreduction and deposition using ZrO2 nanoparticles as the photocatalyst and support. Both highly dispersed Cr(0) and Cr2O3 were found on the surface of the resultant Cr/ZrO2 catalyst after UV irradiation. After photoreduction treatment, no residual chromium was detected in post-treated water. The resultant Cr/ZrO2 was found to be an active catalyst for selective dehydrogenation of ethane. It is slightly more stable and active than that prepared by the impregnation method. The interconversion between the structures of Cr–O–Cr and Cr═O should be the active site for oxidative dehydrogenation of C2H6 with CO2. An ethylene yield as high as 17.0% was achieved at 650 °C. This work proved that producing supported metal catalysts from the corresponding metal contaminated wastewater via proper one-step procedure, such as photoreduction treatment, is a feasible strategy to meet the ever-increasing stringent environmental requirements with better economic efficiency.
研究领域:
环境科学
·
催化化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Hang Yang,Siyu Huang,Yi Zhang,Boxun Zhou,Sanjrani Manzoor Ahmed,Huamin Liu,Yaowen Liu,Yong He,Shibin Xia
In this study, secondary pyrolysis oil-based drilling cuttings ash (OBDCA-sp) was used to remediate chromium (Cr)-contaminated soil. The effects of the OBCDA-sp mesh, OBCDA-sp dosage and soil moisture content on the removal of Cr (VI) were investigated. Subsequently, a kinetic experiment was conducted where the pseudo-first-order and pseudo-second-order kinetic models both fitted well on OBDCA-sp with the adsorption process of Cr (VI) in soil. The change of the chromium form indicated that the addition of OBCDA-sp transformed Cr from an effective state to a stable form, reducing its mobility and bioavailability . X-ray diffraction and Fourier transform infrared spectroscopy analysis were used to verify the potential mechanism of Cr (VI) removal; Ba, Fe, S, and P elements in OBCDA-sp were observed to play a significant role in the reduction of Cr (VI). The results from this study indicate that OBCDA-sp could be an emergent and promising alternative for the remediation of Cr-contaminated soil.
研究领域:
环境科学
·
土壤修复技术
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
·
2022
·
IF 8.943
Xiao Wang,Yanshi Zhang,Yue Zhang,Chunhua Xu
Leaching and chemical reduction are two commonly used methods for Cr(VI)-contaminated soil remediation. Leaching focuses more on leaching Cr(VI) out of the soil. Chemical reduction has the disadvantages of poor fluidity of reductant. Combining these two remediation methods, this study investigated the performance of Cr(VI)-contaminated soil when H 2 O and citric acid were used as eluant separately and sulfidated zero-valent iron (SZVI) as reductant. And based on the properties of Cr(VI) chelated with –COOH to form a complex and the characteristics of –OH anchored to FeS x , citric acid modified SZVI (Cit-SZVI) was prepared. The prepared Cit-SZVI was characterized by SEM-EDS, XPS, XRD to study its surface properties. The transformation of Cr species in soil was explored by BCR sequential extraction. The results indicated Cr(VI) removal by SZVI was significantly promoted when citric acid as eluant compared with H 2 O. With SZVI dosage of 2.0 wt%, 23.1 mg/L Cr(VI) was basically removed within 60 min when citric acid as eluant, while only 60% Cr(VI) was removed when H 2 O as eluant even after 3 h. The k obs of Cit-SZVI was 1.4 times that of SZVI when H 2 O as eluant. The characterization of Cit-SZVI showed that more FeS x was formed on the surface of the Cit-SZVI, and more –OH of citric acid was anchored to FeS x , leaving –COOH available to chelate Cr(VI). Compared with H 2 O as eluant and SZVI/Cit-SZVI as reducing agent, the removal effect of Cr(VI) was the best when citric acid as eluant and SZVI as reducing agent. BCR sequential extraction showed that Cr(VI) was effectually fixed, weak acid extractable Cr proportion decreased significantly and residual Cr proportion increased in the treated soil. The combination of leaching and chemical reduction proposed in this study can greatly enhance the Cr(VI) removal effect in soil, which is important for the remediation of Cr(VI)-contaminated soil.
研究领域:
环境科学
·
土壤修复技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
International Journal of Environmental Science and Technology
·
2023
·
IF 3.1
Zhou B.,Liu Z.,Li Y.,Lv G.,Wang L.,Liu H.,Liao L.
Chromium pollution in ground water is already very serious and needs to be solved urgently. In the present work, the products of natural pyrite after heat treatment were used as the reactive media for permeable reactive barrier. It found that natural pyrite can progressively convert to pyrrhotite with mixed monoclinic and hexagonal structures or pure hexagonal structure at different heat temperatures in argon atmosphere. The products heated at 600 °C had the highest removal of Cr 6+ as compared to pristine pyrite and other heated products. The column experiment showed the service life of the column was 480 PVs. The removal of Cr 6+ mechanisms under the batch and column conditions were also investigated in detail and both of them were redox reactions. The present work suggested that heat-treated natural pyrite has good application prospect as an efficient and low-cost reactive media material in permeable reactive barrier for chromium pollution control.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
WATER AIR AND SOIL POLLUTION
·
2020
·Vol. 231
·期 5
·1-10
·
IF 1.9
Wang Ning,Zhang Feiyan,Mei Qiufeng,Wu Ronglan,Wang Wei
The harm of chromium pollution to the environment has caused a widespread concern; hexavalent chromium is a toxic, cancerogenic, and genetically mutagenic contaminant to the human body; by contrast, trivalent chromium is almost non-toxic to the human body; therefore, it is a feasible method to reduce hexavalent chromium to trivalent chromium. Photocatalysis is a new environmentally friendly and harmless technology, which can transform pollutants into non-toxic or less toxic products. In this study, we synthesized TiO 2 /rGO/CuO ternary nanocomposites to treat hexavalent chromium pollution under visible light. Under optimal conditions, the photoreduction efficiency of 100 ppm hexavalent chromium solution could reach 100% in 80 min. The photoreduction rate of hexavalent chromium is 29.4 times than that of pure TiO 2 . The photocatalytic property of CuO in TG2C8 nanocomposites is attributed to accelerate the separation of electrons and holes and the efficient electron transfer through the rGO framework. We believe that TiO 2 /rGO/CuO composites have great potential in wastewater treatment.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2022
·Vol. 29
·期 29
·44845-44861
·
IF 5.19
Wang Jiangyuan,Yu Qiu,Zheng Yi,Li Jing,Jiao Binquan,Li Dongwei
Toxic metal pollutant Cr(VI) in the environment will pose a severe threat to animal and human health. In this work, Fe 3 O 4 @PPy, Arg@PPy, and Arg/Fe 3 O 4 @PPy were prepared to enhance adsorption of Cr(VI) by doping Fe 3 O 4 nanoparticles and amino radicals into the original PPy structure. Their characteristics were investigated by FTIR, SEM, EDS, BET analysis, and batch adsorption experiments. And they were used as permeable reaction barriers (PRB) to combine with electrokinetic remediation (EKR) to remediate Cr-contaminated soil. Adsorption experiment results showed that the maximum adsorption capacities of PPy, Fe 3 O 4 @PPy, Arg@PPy, and Arg/Fe 3 O 4 @PPy for Cr(VI) were 60.43 mg/g, 67.12 mg/g, 159.86 mg/g, and 141.50 mg/g, respectively. They all followed the kinetic pseudo-second-order model and the Langmuir isothermal model with a monolayer adsorption behavior. In the EKR/PRB system, the presence of Fe 3 O 4 @PPy, Arg@PPy, and Arg/Fe 3 O 4 @PPy obtained the higher Cr(VI) removal efficiency near the anode than that of the PPy, increasing by 74.60%, 26.04%, and 68.64%, respectively. A strong electrostatic attraction between anion contaminants and protonated modified PPy and a reduction from Cr(VI) to Cr(III) appeared in the EKR remediation process under acid conditions. This study opened up a prospect for applying modified PPy composites to treat toxic metal-contaminated soil.
研究领域:
环境科学
·
材料科学
·
土壤修复
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Chen Wang,Xiaohui Wu,Mingjie Huang,Tao Zhou,Juan Mao,Xiangling Zhang
Treatment of Cr(VI)-contaminated wastewaters by conventional reduction methods has been intensively challenged by alkaline environments. In this study, a novel copper-iron oxide composite (Cit@CuFeO) enriched with oxygen vacancies (OVs) was developed by ball milling with citric acid ligand (Cit). The material demonstrated efficient Cr(VI) removal within a broad pH range (6.0–12.0). Intriguingly, simultaneous and nearly complete in-situ immobilization of Cr(III) occurred, instead of precipitated in strong alkaline circumstances. Characterizations of the Cit@CuFeO revealed that ball milling of Cit could introduce abundant OVs into the oxide structure, serving as pivotal active sites linearly correlated with Cr(VI) capture and removal. These generated OVs could also boost electron conduction in Cit@CuFeO and cause a positive shift in the zeta potential , thereby enabling the adsorption of negative CrO 4 2- at high pH. Furthermore, DFT calculation verified that the surface-attached Cit would significantly decrease the adsorption energy of Cr(VI) at OVs sites, competitively excluding the occupancy of common inorganic anions especially CO 3 2– and thus favoring the Cr(III) immobilization under alkaline conditions. This study has provided a green functional material for the one-step remediation of alkaline Cr(VI) wastewaters without the need for acidification.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2021
·
IF 5.909
Xiao He,Guodong Cui,Qiming Zhang,Zheng Wang,Tian Tang,Yangsheng Liu
A modified electrokinetic remediation (EKR) system was designed to remediate Cr-contaminated soil using sulfidated nano-scale zerovalent iron (S-nZVI) as the third electrode. This study systematically compared the technological parameters and remediation efficiencies of three-dimensional (3D) electrokinetic systems using different materials as the third electrodes. The comparative experiment showed that the 3D EKR could effectively increase current efficiency, balance voltage distribution, alleviate excessive acidification or alkalization of soils and effectively improve the removal efficiency of Cr. Compared with other 3D electrodes, the S-nZVI electrode led to the higher currents and the more uniform voltage distribution; additionally, the leaching toxicities were reduced by 50.0–66.7%, and the removal efficiencies of total Cr (Cr(tot)) and hexavalent Cr (Cr(VI)) were increased by at least 15.4% and 22.6%, respectively. Cr(VI) was removed mainly resulting from the electrokinetic migration. Meanwhile, a small amount of Cr(Ⅵ) was converted to FeCr 2 O 4 and Cr 3+ OOH after reacting with S-nZVI in the middle region of the 3D EKR system. Due to the active layer of iron sulfides , S-nZVI was more stable and its electrokinetic efficiency was higher than other 3D electrodes, resulting in higher overall removal efficiencies. 3D EKR with S-nZVI can effectively decrease the toxicological effect of Cr contaminated soil at an experimental scale. The experimental findings from this study may provide a reference for guiding the development of more efficient methods for Cr-contaminated soil treatment.
研究领域:
环境科学
·
土壤修复
✓ 已验证
产品关联
DOI
高影响因子
Desalination and Water Treatment
·
2025
·
IF 1
Hongliang Zhang,Wensheng Tang
In this study, a polyethyleneimine (PEI)-modified magnetic sludge biochar (N@FeBC) was prepared via coprecipitation and impregnation methods for treating Cr(VI) contamination in aqueous and soils. Under conditions of pH 3 and 298 K, N@FeBC exhibited a utmost Cr(VI) removal amount of 82.97 mg/g. The removal behaviors were most accurately characterized the pseudo-second-order and Langmuir model. Thermodynamics analysis revealed that the reactions were spontaneous, endothermic, and accompanied by increased system entropy. The removal capacities progressively decreased as the pH rose from 2 to 10, with the optimal removal amounts occurring under acidic conditions. While coexisting cations had negligible effects on Cr(VI) adsorption, anions inhibited the process to varying degrees. Interestingly, humic acid presence improved the efficiencies of Cr(VI) removal. Notably, N@FeBC reduced low-concentrations of Cr(VI) in various water matrices to below the WHO drinking water standard (0.05 mg/L), and retained excellent performance after 15 reuse cycles. In soil stabilization tests, N@FeBC more effectively reduced Cr(VI) toxicity in contaminated soil. Mechanistic investigations revealed that Cr(VI) removal occurred via electrostatic attraction to protonated surface functionalities, partial reduction to Cr(III), and subsequent coordination with functional groups. This study indicates that N@FeBC can serve as an efficient material for removing Cr(VI) contamination.
研究领域:
环境科学
·
化学工程
·
材料科学
·
水处理技术
·
土壤修复
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）