WATER RESEARCH
·
2025
·
IF 12.4
Shichao Cai,Yurou Tan,Hongyi Li,Bo Chen,Feng He
Sulfidated microscale zero-valent iron (S-mZVI) is a promising ZVI material for remediation of chlorinated hydrocarbons (CHCs). However, the structure and dechlorination behavior change of S-mZVI induced by sulfophilic metal (Me) ions in groundwater are barely studied. Here we show that Me ion-amended S-mZVI (S-mZVI Me ) have a rate sequence of S-mZVI Co >S-mZVI Ni >S-mZVI>S-mZVI Cu >S-mZVI Cd ≈ S-mZVI Zn and S-mZVI Ni >S-mZVI Cd >S-mZVI ≈ S-mZVI Zn ≈ S-mZVI Cu ≈ S-mZVI Co for trichlorethylene (TCE) dechlorination and hydrogen evolution reaction (HER), respectively. This results in the highest ever reported electron efficiency (98.6%) for TCE dechlorination by S-mZVI Co . Cross-section SEM-EDS, XRD, and XPS analyses confirm the formation of MeS x on the surface of all S-mZVI Me . Additionally, Ni 0 , Cu 0 , and possibly Cd° formed on the S-mZVI Ni , S-mZVI Cu , and S-mZVI Cd , respectively. Theoretical calculations indicate that the nascent metal sulfides are more hydrophobic than FeS, indicating the faster HER with Ni and Cd amendment is likely due to formation of bimetallic structures. Correlation analyses suggest that both low band gap and high work function of the semi-conductive Co sulfide contribute to the high reactivity of S-mZVI Co . Column studies further show that implementing Co 2+ enables the dechlorination of TCE from 2000 µg/L to < 70 µg/L up to 1000 pore volumes by S-mZVI, compared to > 1.2 mg/L without Co 2+ . These findings have important implications for remediation of CHC-contaminated sites using S-mZVI.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Chemical Engineering and Processing-Process Intensification
·
2018
·
IF 2.826
Qing-nan Liu,Liang Cheng,Xue-bing Xu,Hong Meng,Ying-zhou Lu,Chun-xi Li
Calcium carbide (CaC 2 ) is a potential feedstock for various alkynyl chemicals, but its actual activity is very low due to its high lattice energy and insolubility. A stirring ball mill was used here to intensify its reaction with perchloro-hydrocarbons (PCHCs), namely hexachlorobenzene (HCB), hexachloroethane (HCE), tetrachloroethene (TCE) and tetrachloromethane (TCM), forming corresponding alkynyl carbon materials (ACMs), viz. ACM HCB , ACM HCE , ACM TCE and ACM TCM , respectively. The reaction intensification may be ascribed to the activation of CaC 2 and its effective collision with PCHCs by the intensive impingement of the milling balls. The as-prepared ACMs were characterized by XRD, Raman, elemental analysis, XPS, SEM and BET analysis, and their adsorption performance was evaluated. These ACMs are mesoporous materials with over 70% carbon content, varying amount of acetylenic groups, rich micro-pores and high specific areas ranging from 270 to 970 m 2 g −1 . ACM HCB is found to be a promising sorbent with adsorption capacity of 514.7 mg-Hg g −1 for HgCl 2 aqueous solution and 24.4 mg-S g −1 for DBT oil, which is much superior to most of carbonaceous sorbents due to its rich micro-porosity and abundant acetylenic groups.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Xuanran Zhao,Wei Wang,Xin Song,Enwei Cao,Xueqiang Zhu,Shuguang Lyu
In this work, the effect of bromide ion (Br – ) on 1,2,3-trichloropropane (TCP) and trichloroethylene (TCE) degradation in hydrogen peroxide (H 2 O 2 ), peroxymonosulfate (PMS), and peroxydisulfate (PDS) oxidation processes was investigated. In ultrapure water, 100 %, 90 %, and 47.2 % TCE could be removed in H 2 O 2 /Fe(II), PMS/Fe(II), and PDS/Fe(II) systems within 60 min at selected dosages, respectively, while only H 2 O 2 /Fe(II) system was efficient for TCP removal (82.5 %). Compared with TCE, the negative effect of Br – on TCP removal was more obvious due to the poor TCP degradation by reactive halogen species. Besides, hydroxy radical (HO•)-based system (H 2 O 2 /Fe(II)) was more sensitive to Br – than sulfate radical (SO 4 – •)-based systems (PMS/Fe(II) and PDS/Fe(II)), because HO• was prone to react with Br – with a greater reaction rate constant. In the presence of Br – , the addition of citric acid or zero-valent iron (ZVI) promoted TCP and TCE degradation in SO 4 – •-mediated systems, while TCP and TCE removal in HO•-based system could be slightly enhanced by ZVI. In actual groundwater tests, both pre-adjusting solution pH to acidity for TCE removal in HO•-driven system and increasing chemical dosages in SO 4 – •-based systems could effectively degrade the target pollutants in the presence of Br – .
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
WATER ENVIRONMENT RESEARCH
·
2019
·Vol. 92
·期 4
·622-630
·
IF 1.24
Xuecheng Sun,Yong Sun,Shuguang Lyu,Zhaofu Qiu,Qian Sui
In this study, nano-CaO 2 (nCaO 2 ) was successfully synthesized and constituted the nCaO 2 /Fe(II) system applying to remediate BTEX, which are typical mixed pollutants in contaminated groundwater. The particle size of the synthesized nCaO 2 was 108.91 nm, and it displayed better BTEX remediation performance than that of commercial CaO 2 . The innovative generation pattern of hydroxyl radicals ( ) in the nCaO 2 /Fe(II) system has been investigated using benzoic acid as the probe, and the proper molar ratio of nCaO 2 /Fe(II) was optimized as 1/1. Over 90% of BTEX was removed in 180 min with the nCaO 2 /Fe(II)/BTEX molar ratio of 40/40/1. Further experiments evaluated the influence of co-existence of mixed pollutants chlorinated hydrocarbon compounds (CHCs) or surfactant constituents on BTEX remediation performance. The experimental results suggested that CHCs have limited influence on BTEX removal rate and surfactants have negative effects on BTEX remediation performance in the experimental conditions. In conclusion, the findings in this study could give some inspirations to apply the nCaO 2 /Fe(II) process in remediating co-existing pollutants in contaminated groundwater. Practitioner points nCaO 2 /Fe(II) system applied to remediate mixed contaminants. generation pattern of the nCaO 2 /Fe(II) system has been investigated. The influence of chloride hydrocarbon compounds have been studied. The effects of surfactants were evaluated.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Analytical Methods
·
2015
·Vol. 7
·期 22
·9619-9628
·
IF 1.821
Dazhong Shen,Xiaolong Ma,Tingting Cai,Xilei Zhu,Xiaodong Xin,Qi Kang
In this work, the kinetic processes of zeolitic imidazolate framework-8 (ZIF-8) film growth and the adsorption of dichloromethane (DCM), trichloromethane (TCM) and carbon tetrachloride (CTC) on ZIF-8 film are monitored in real time using a quartz crystal microbalance sensor. It is shown that the growth kinetics of ZIF-8 film from a mixture of zinc nitrate and 2-methylimidazole consists of a rapid initial growth (0.22–1.1 μg cm−2 min−1) and later slow rearrangement stages. The time to obtain 50% of total equilibrium grown mass is in the range of 5.1–6.8 min. The mass deposited in the second, third and fourth cycles is 2.37, 3.36 and 4.08 times that in the first one (3.11 μg cm−2), respectively, and approaches a stable level after the fourth cycle. The as-prepared ZIF-8 film (0.70 μm) exhibits adsorption capacities of 568.3, 496.7 and 212.8 mg g−1 to DCM, TCM and CTC (20 °C), respectively. The initial adsorption rate of DCM is much higher than that of TCM and CTC. The difference in the adsorption behavior of the three chlorohydrocarbons is ascribed to the sieve effect of the pore apertures in ZIF-8 to the adsorbates. The adsorption kinetic data are in agreement with the pseudo-second-order model. For the adsorption in ZIF-8 film, the adsorption activation energies are 34.9 ± 5.6, 66.9 ± 5.5 and 49.1 ± 3.8 kJ mol−1; standard enthalpy changes of −63.2, −89.1 and −119 J mol−1, and standard entropy changes of −41.9, −45.3, and −50.1 kJ mol−1 K−1 have been evaluated for DCM, TCM and CTC respectively. The adsorption isotherms of DCM and TCM at 20 °C are fitted well by the Langmuir model while those of CTC and TCM at 60 °C follow the Freundlich model.
研究领域:
材料科学
·
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Yanping Cui,Haodong Yang,Xian Xiang,Shibo Zhao,Qiao Huang,Zhaoqiang Huang
A modified graphite felt (MGF) was prepared with carbon black (CB) and polytetrafluoron (PTFE) for cathodic electrochemical H 2 O 2 production, which was used in a flow-through cathodic electro-Fenton reactor to degrade chlorinated hydrocarbons. Cathode electrode was floating on aqueous surface and 369.1 mg/L H 2 O 2 could be produced after 1 h 150 mA power applied without O 2 aeration. The main O 2 source for H 2 O 2 production was confirmed from air with this floating position. In a 2.0 L flow-through cathodic electro-Fenton system, 95.97 % degradation efficiency for 5.0 mg/L trichloroethylene (TCE) was achieved in 90 min with 13.4 mL/min influent rate. Reducing the reactor volume to 0.14 L, 5.0 mg/L TCE could be degraded completely in 10 min with continuous 4 L influent. The mixed chlorinated hydrocarbons (TCE, cis -1,1-dichloroethylene, 1,2-dichloroethane, and dichloromethane) were also rapidly degraded in 20 min. The flow-through cathodic electro-Fenton reactor presented excellent degradation ability for chlorinated hydrocarbons with a smaller volume. In the simulated sand tank system, after continuously operated 27 days, H 2 O 2 concentration in electrode well was still remained at 80 mg/L. In the contaminated field in Tianjin, China, H 2 O 2 yield of MGF in groundwater could keep at about 60 mg/L after 220 min operating.
研究领域:
环境科学
·
电化学工程
✓ 已验证
产品关联
DOI
高影响因子
Nature Communications
·
2025
·Vol. 16
·期 1
·1-10
·
IF 15.7
Lin Simin,Wang Xubin,Li Huisi,Zhou Jiancheng,Wen Ruijuan,Ma Jianfei,Yin Shiwei,Peng Ling-Ya,Peng Haonan,Fang Yu
Excitation-dependent multicolor emission from a single-component system, independent of aggregation, remains a fundamental challenge due to inherent difficulties in innovative principles. Herein, we propose a molecular symmetry-breaking strategy to enrich electronic processes, enabling the molecule to exhibit excitation-dependent multicolor emissions from one chemical entity. A star-shaped molecule, 1,3,5-(4- tert -butylphenyl- o -carboranyl-4-phenyl)benzene (Ph-3CP) is designed, where spatial restriction induces inequivalence among three bulky, non-planar branches. This asymmetry gives rise to a broad excitation-dependent emission range of nearly 175 nm across solution, amorphous, and crystalline states. Crystallization from different solvents successfully traps distinct asymmetric conformers of Ph-3CP, providing direct experimental evidence for the predicted symmetry-breaking structures from theoretical calculations. Structure-property relationship studies further reveal two distinct relaxation pathways that dominate the emission behavior of this molecular system. Leveraging these properties, we develop a single-component fluorescence sensor array that enables rapid and selective identification of chlorinated hydrocarbon vapors. This work provides a general strategy for designing multifunctional luminescent materials through symmetry-controlled excited-state engineering.
研究领域:
材料化学
·
光物理
·
超分子化学
·
有机电子学
·
传感技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）