HYDROMETALLURGY
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2020
·
IF 3.338
Xi Chen,Xincun Tang,Zhihao Rong,Liping Wu,Pin Deng,Yang Wang,Xing Li,Liuchun Huang,Wei Dang
This paper presents an eco-friendly method for recovery of cadmium by solvent extraction and stabilization of arsenic through one-pool treatment on arsenic-rich flue dust. The morphology-controlled scorodite can be realized by adjusting reaction temperature. It is worth emphasizing that the arsenic-immobilized scorodite precipitates have superior crystallinity which exhibit excellent safety for long-term storage. In addition, the advantage brought about by taking hydrogen peroxide as leaching agent is that leachate is weakly acidic, which removes the need to add a large amount of neutralizing agent and facilitates the synthesis of scorodite. The results show that 97.3% of arsenic was leached from arsenic-rich flue dust and then 92.8% of the leached arsenic was transferred into scorodite with the recovery of 81.5% of cadmium under the optimal conditions. We hope that this work will provide a facile and environmentally friendly protocol for those interested in developing a new strategy for simultaneously recovering and stabilizing toxic heavy metal ions from industrial dust.
研究领域:
环境科学
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冶金工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
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2023
·Vol. 34
·期 11
·1-16
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IF 2.8
Shi Jiahao,Duan Xiaoxu,Qi Xianjin,Li Guohua,Yan Guizhi,Wang Heng
Acidic arsenic-containing wastewater from copper smelting poses a potential threat to human and environmental safety due to its high toxicity, acidity, high volumes, and difficulty to be processed and utilized. This study proposed a technique to leach environmentally stable scorodite from wastewater using natural zinc slag as a solid iron source. The leaching behavior of scorodite was investigated through a combination of room-temperature adsorption and high-temperature reactions, after which the underlying mechanisms of this reaction were explored through adsorption kinetics and thermodynamics. Our findings indicated that the optimal reaction conditions of zinc slag with wastewater were the following: Fe/As ratio = 2.5, 80 °C, 10 h. The initial arsenic concentration in the wastewater was reduced from 13,040 mg/L to 140.5 mg/L, with 98.9% of the arsenic being removed. The toxicity characteristic leaching procedure (TCLP) results for the precipitates showed that the leaching concentration of arsenic was only 2 mg/L. For Fe 2 SiO 4 in zinc slag, FeS dissolves to release iron ions, generating FeAsO 4 ·2H 2 O, FeAsO 4 , and secondary minerals. Ca 2 Al 2 SiO 7 generates gypsum to provide surface active sites for the growth of scorodite. This study proposes the industrial application of zinc slag for arsenic removal from copper smelting wastewater, providing a strong methodological basis to promote the development of non-ferrous metallurgical enterprises in a green and efficient manner.
研究领域:
环境科学
·
冶金工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
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2023
·
IF 6.1
Yongkui Li,Xianjin Qi,Guohua Li,Heng Wang,Guizhi Yan,Jiahao Shi
As-containing acidic wastewater from the nonferrous heavy smelting industry is a hazardous As pollution source due to its complex composition, high acidity, and strong toxicity. In this study, an environmentally friendly strategy was proposed to simultaneously remove and immobilize As from acidic wastewater through the synthesis of highly stable scorodite using natural magnetite ore as Fe resource. Firstly, the magnetite ore was dissolved in wastewater to provide a certain amount of starting Fe source for the subsequent arsenic precipitation while creating a suitable pH environment for the synthesis of scorodite. Subsequently, the released Fe ions reacted with As ions in wastewater with undissolved magnetite ore as the nuclear site to form amorphous ferric arsenate, which was then transformed into a well-crystallized scorodite precipitate, thus achieving the As removal and immobilization. Under the optimal reaction conditions, including a Fe/As molar ratio of 2.5, a pre-dissolution time of 5 h, an initial pH of 2.0, a reaction time of 24 h, and a reaction temperature of 90 °C, the residual As concentration in the wastewater rapidly reduced from initial 6259.00 mg/L to 3.76 mg/L, corresponding to an arsenic removal efficiency of 99.94%, and the leaching As concentration in scorodite was 0.42 mg/L. This study provides an efficient and environmentally friendly method for the disposal of high As-containing wastewater from nonferrous smelting.
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
Environmental Science-Water Research & Technology
·
2022
·Vol. 8
·期 11
·2796-2806
·
IF 5.819
Guohua Li,Xianjin Qi,Jiahao Shi,Guizhi Yan,Heng Wang,Aimin Zhang
Arsenic (As) pollution is a serious worldwide problem that requires urgent attention, as this heavy metal poses a serious threat to both human and environmental health. Here, Fe3O4 was used as an in situ Fe source removal agent to study the effect of pre-dissolution time on arsenic removal by Fe3O4. Fe3O4 is uniquely well suited for the treatment of industrial wastewater due to its structural characteristics. Assays were conducted at a Fe/As molar ratio of 3 : 1, and these components were pre-dissolved at 23 °C for 2 h to establish the optimal initial conditions for Fe-mediated arsenic removal at a high temperature. The adsorption capacity of arsenic in the pre-dissolution stage was 143.99 mg g−1. After adjusting the pH value to 2.5 and allowing the Fe and As to react at 90 °C for 24 h, 99.1% of the As was precipitated from the wastewater with an initial arsenic concentration of 8276.1 mg L−1. The leaching of this As-bearing precipitate was as low as 0.3 mg L−1. As a solid iron source, Fe3O4 provides a large number of nuclear sites for arsenic precipitation in the pre-dissolution stage and the high-temperature synthesis stage. At the same time, the supersaturation of the system was regulated by controlling the reaction and dissolution characteristics. Upon further characterization, the removal of As by Fe3O4 in the pre-dissolution process was attributed to a combination of physical adsorption and chemical precipitation.
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
危险品化学品经营许可证（带存储）