JOURNAL OF HAZARDOUS MATERIALS
·
2022
·
IF 14.224
Peng Wang,Jian Hu,Yidong Wang,Tingyi Liu
The ball-milling technology , a highly efficient and cost-effective method, had excellent application prospects for overcoming passivation issues of normal zero-valent iron (ZVI) to enhance the decontamination efficiency. In this work, we investigated the effects and mechanisms of pH, process control agents (PCA), and main process parameters on the removal of V 5+ using ball-milled zero-valent iron (ZVI bm ). The results showed that ZVI was successfully activated due to mechanochemical action. The enhanced proton conductivity of ZVI bm leaded to the rapid production of more Fe 2+ , thereby resulting in an order of magnitude higher elimination of V 5+ by ZVI bm than by ZVI under near-neutral conditions. In addition, the introduction of NaCl in the ball milling process could not only effectively alleviate the agglomeration phenomenon of ZVI bm , but also effectively enhance its activity. Unexpectedly, due to over-compaction and small size effects, excessive energy input weakened the reactivity of ZVI bm on V 5+ elimination. Various characterization results confirmed that the removal of V 5+ by ZVI bm was dominated by reduction and supplemented by adsorption. This work updated the basic understanding of the critical effects of process parameters and NaCl on ZVI bm in the remediation of vanadium-containing wastewater.
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
Scientific Reports
·
2017
·Vol. 7
·期 1
·1-10
·
IF 4.259
Gao Yuchen,Jiang Jianguo,Tian Sicong,Li Kaimin,Yan Feng,Liu Nuo,Yang Meng,Chen Xuejing
Soil washing is an effective remediation method to remove heavy metals from contaminated soil. However, it produces wastewater that contains large amounts of heavy metals, which lead to serious pollution. This study investigated the removal of vanadium (V) from synthetic soil washing effluent using BOF steel slag. The effects of particle size, slag dosage, initial pH, and initial vanadium concentration on removal behavior were studied. Adsorption kinetics and isotherms were also analyzed. The results showed that the vanadium removal efficiency increased as the steel slag particle size decreased and as the amount of slag increased. The initial pH and vanadium concentration did not play key roles. At the optimum particle size (<0.15 mm) and dosage (50 g/L), the removal rate reached 97.1% when treating 100 mg/L of vanadium. The influence of the washing reagent residue was studied to simulate real conditions. Citric acid, tartaric acid, and Na 2 EDTA all decreased the removal rate. While oxalic acid did not have negative effects on vanadium removal at concentrations of 0.05–0.2 mol/L, which was proved by experiments using real washing effluents. Considering both soil washing effect and effluent treatment, oxalic acid of 0.2 mol/L is recommended as soil washing reagent.
研究领域:
环境科学
·
土壤修复
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2015
·
IF 3.352
Hui Shang,Yu Liu,Jin-Chun Shi,Quan Shi,Wen-Hui Zhang
Most crude oils contain traces of metal complexes, among which vanadium (V) and nickel (Ni) compounds are the most harmful poisons to the catalysts of fluid catalytic cracking (FCC) and hydrogenation units. These metals are proven to be extremely hard to remove, since they exist in crude oil as stable oil-soluble complexes. The microwave technology provides a new way for Ni/V removal, their removal efficiency using chemical reagents and the mechanism of microwave-assisted demetallization were studied in this paper. It was concluded that the demetallization efficiency can be highly enhanced under microwave irradiation . There is no specific structural selectivity for vanadium porphyrins during microwave treatment process. The demetallization agent — methanesulfonic acid , containing a sulfonyl acid group was found to react with VO 2 + and Ni 2 + . Ni and V were removed from porphyrin ring without destroying the ring structure, corresponding water soluble inorganic salts were formed, thus can be successfully separated from crude oil by washing or desalting process.
研究领域:
化学工程
·
石油加工
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Catalysts
·
2022
·Vol. 12
·期 11
·1469
·
IF 4.501
Yilin Huang,Jia Wang,Mengwei Li,Zhixiong You
We have successfully synthesized dithiocarbamate chitosan modified SBA-15 (CS2C@SBA) composites, with promise in vanadium (V(V)) elimination. Among the three composites using different mass ratios of dithiocarbamate chitosan to SBA-15, CS2C@SBA−3, which had the highest CS2substitution, showed the best performance on V(V) removal of which the maximum adsorption capacity could achieve 218.00 mg/g at pH 3.0. The adsorption kinetics were best fitted with a pseudo−second order reaction model, suggesting a chemisorption mechanism. Meanwhile, the Langmuir model fitted better with the adsorption isotherm, revealing a monolayer adsorption behavior. Through FTIR and XPS analysis, the functional group −SH was identified as dominating reduction sites on this composite, which reduced 73.1% of V(V) into V(IV) and V(III). The functional group −NH− was the main adsorption site for vanadium species. This reaction followed a catalytic reduction coupled adsorption mechanism reducing most of V(V) into less toxic vanadium species. Furthermore, CS2C@SBA−3 showed great selectivity towards V(V) in the presence of various co−existing ions in synthetic wastewater and real water samples. Moreover, CS2C@SBA−3 could retain a removal efficiency over 90% after five adsorption−desorption cycles. Based on the aforementioned results, we can conclude that CS2C@SBA−3 has great potential to be applied in efficient remediation of vanadium water−pollution.Keywords:vanadium elimination;adsorption;catalytic reduction;thiol function group;dithiocarbamate chitosan modified SBA-15
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
危险品化学品经营许可证（带存储）