Materials
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2022
·Vol. 15
·期 21
·7471
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IF 3.748
Pan Chen,Yuxin Zhao,Jun Yao,Jianyu Zhu,Jian Cao
In situ treatment of acidic arsenic-containing wastewater from the non-ferrous metal smelting industry has been a great challenge for cleaner production in smelters. Scorodite and iron arsenate have been proved to be good arsenic-fixing minerals; thus, we used lead slag as an iron source to remove arsenic from wastewater by forming iron arsenate and scorodite. As the main contaminant in wastewater, As(III) was oxidized to As(V) by H2O2, which was further mineralized to low-crystalline iron arsenate by Fe(III) and Fe(II) released by lead slag (in situ generated). The calcium ions released from the dissolved lead slag combined with sulfate to form well-crystallized gypsum, which co-precipitated with iron arsenate and provided attachment sites for iron arsenate. In addition, a silicate colloid was generated from dissolved silicate minerals wrapped around the As-bearing precipitate particles, which reduced the arsenic-leaching toxicity. A 99.95% removal efficiency of arsenic with initial concentration of 6500 mg/L was reached when the solid–liquid ratio was 1:10 and after 12 h of reaction at room temperature. Moreover, the leaching toxicity of As-bearing precipitate was 3.36 mg/L (As) and 2.93 mg/L (Pb), lower than the leaching threshold (5 mg/L). This work can promote the joint treatment of slag and wastewater in smelters, which is conducive to the long-term development of resource utilization and clean production.Keywords:arsenic wastewater;lead slag;iron arsenate;scorodite
研究领域:
环境科学
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冶金工程
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DOI
PubMed
高影响因子
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
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2025
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IF 7.8
Hang Chen,Xiong Tong,Ruiqi Xie,Xian Xie,Pulin Dai,Qiang Song,Peiqiang Fan,Yuanlin Ma
In industrial production, lime on the pyrrhotite surface need to be removed using inorganic acids for activated flotation. However, inorganic acid reagents need to be replaced due to their causing severe environmental disasters with large consumption. In this study, the effects of two green organic acids with structures similar to that of pyrrhotite were investigated by micro-flotation experiments and density functional theory (DFT) calculations.The flotation experiments of micro and actual ore confirmed that oxalic acid could effectively reduce lime from the pyrrhotite surface. In the micro flotation experiment, the pyrrhotite recovery increases from 10.98% to 83.7% when the lime dosage is 500 mg/L, oxalic acid dosage 8.0 × 10 -3 mol/L at an acidic environment with pH is 5. But, the recovery only increases from 6.15% to 19.24%, when the acetic acid was added with a dosage of 16 × 10 -3 mol/L and pH is 6. Further investigation using DFT and frontier molecular orbital theory revealed that oxalic acid could increase the charge exchange with Ca 2+ in CaOH + due to its double carboxyl group structure. Therefore, the resulting Ca-O bonds are stronger than the Ca-S bonds formed between CaOH + and the mineral surface. Consequently, the Ca-S bonds break. Due to its single carboxyl group structure, acetic acid exhibits a weaker charge exchange capability than oxalic acid and does not cause the complete breaking of the Ca-S bonds. The actual ore closed-circuit test further verified that the iron concentrate grade was 2.13% and the sulfur grade was reduced by 90.15%. These findings highlight the potential of oxalic acid as a more sustainable and environmentally friendly substitute for inorganic acids, offering improved flotation performance while reducing the environmental impact of minerals separation.
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高影响因子
Results in Engineering
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2025
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IF 7.9
Baojun Yang,Xin Zhang,Yuling Liu,Xin Sun,Yang Liu,Jun Wang,Shitong Liu,Rui Liao,Guanzhou Qiu
Arsenopyrite is an important gold-bearing sulfide mineral, and pretreatment is essential before gold extraction to maximize gold recovery. Bioleaching, with its advantages of simple operation and environmental friendliness, has received widespread attention over the past decade. However, the low efficiency and long cycle of bioleaching hinder its large-scale application. Humic acid (HA) is a potential substance that can enhance the bioleaching of arsenopyrite and has advantages such as ease of acquisition, and environmental friendliness. Currently, there is a lack of research on the promoting effect and mechanism of HA on the bioleaching of arsenopyrite under the action of mesophile microorganism. This study investigates the effects of HA mediated by Acidithiobacillus ferrooxidans on the arsenopyrite leaching behavior, the valence states and forms of arsenic. The results showed HA can promote the bioleaching of arsenopyrite and shorten the leaching cycle. The addition of 20 mg/L HA can significantly reduce the bioleaching cycle of arsenopyrite from 14 days (without HA) to 6 days. HA can promote the growth of microorganisms and enhance the Fe/S oxidation capacity of microorganisms. Meanwhile, HA can adsorb onto the mineral surface, facilitating the oxidation of arsenopyrite by Fe 3+ adsorbed by HA, thereby promoting the bioleaching of arsenopyrite. This study offers new insights into shortening arsenopyrite bioleaching cycle.
研究领域:
生物冶金
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环境生物技术
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微生物学
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地球化学
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DOI
高影响因子
APPLIED SURFACE SCIENCE
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2025
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IF 6.9
Zhicong Wei,Junnan Qu,Peilun Shen,Haokai Di,Yang Liu,Liuyang Dong,Yan Huan,Yanling Jin,Haiyun Xie,Qihao Gui,Dianwen Liu
Arsenopyrite, as the main carrier of precious metals and a companion mineral of sulfide ores, needs to be removed in advance before entering the metallurgy process to reduce its impact. The catalytic role of chalcopyrite in enhancing arsenopyrite oxidation under sulfate radical-based advanced oxidation processes (SR-AOPs) was systematically investigated. Through multi-scale characterization (XRD, SEM-EDS, XPS, FTIR, Tof-SIMS, EPR) and electrochemical analysis (OCP, CV, Tafel), this study demonstrates that chalcopyrite significantly accelerates arsenopyrite oxidation. Electrochemical analysis indicates that Chpy optimizes the electron transfer pathway and accelerates the oxidation process of pyrite. Surface analysis identified α-FeOOH/As–O oxide layers and Cu-As/S complexes as critical intermediates. The EPR and quenching experiments demonstrated that multiple activation pathways of chalcopyrite effectively promoted the free radical conversion rate of PDS and enhanced the oxidation efficiency of arsenopyrite. These findings provide mechanistic insights into chalcopyrite-driven arsenopyrite oxidation, offering a sustainable strategy for arsenic removal with reduced reagent consumption.
研究领域:
环境化学
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矿物加工
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冶金工程
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表面科学
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电化学
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自由基化学
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硫化物矿物氧化
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DOI
高影响因子
危险品化学品经营许可证（带存储）