Journal of Central South University
·
2021
·Vol. 28
·期 9
·2701-2710
·
IF 1.716
Zhang Du-chao,Liu Ruo-lin,Wang Hao,Liu Wei-feng,Yang Tian-zu,Chen Lin
To recover zinc from electric arc furnace (EAF) dust, a process of primary normal pressure leaching and secondary alkaline pressure leaching is proposed. First, under the alkaline pressure leaching system, the experiment of pure zinc ferrite being reduced by iron powder was carried out. Under the optimal reduction conditions (i.e., temperature of 260 °C, NaOH concentration of 6 mol/L, liquid-to-solid ratio of 50 mL/g, and a 5-fold excess of iron powder), 89% of zinc was extracted. The iron in the reduced residue exists as a magnetite phase. Subsequently, the normal pressure leaching experiment was carried out with EAF dust as raw material, and 66% zinc was leached. The main phase of zinc in normal leaching residue was determined to be zinc ferrite. Then, the normal leaching residue was reduced by iron powder under the alkaline pressure leaching system, and 66.5% of zinc was extracted. After the two-stage leaching process, the leaching rate of zinc in EAF dust can achieve 88.7%. The alkaline pressure leaching solution can be returned as the normal pressure leaching solution, and the magnetite in the alkaline pressure leaching residue can be recovered by magnetic separation.
研究领域:
冶金工程
·
环境工程
✓ 已验证
DOI
高影响因子
Journal of Cleaner Production
·
2022
·
IF 11.072
Yingjie Xu,Hongying Xia,Qi Zhang,Wuchen Cai,Guiyu Jiang,Libo Zhang
Germanium-containing dust as an intermediate by-product in the process of zinc hydrometallurgy , which often contains a large number of heavy metal substances. Due to the constraints of economic benefits and process technology, green and efficient treatment of germanium-containing dust is always a great challenge. In this work, XRD , ICP-OES, XPS , SEM and other characterization methods were used to analyze the existing state and quantity of main substances in germanium-containing dust. It was found that the occurrence state of germanium was closely related to sphalerite . At the same time, longer reaction time would lead to continuous hydrolysis of silicate, which would eventually affect the recovery of zinc, germanium and lead and the fixation of toxic substances. Therefore, the ultrasonic enhanced ammonium persulfate oxidation process was proposed to control the waste of resources and environmental pollution caused by the accumulation of germanium-containing dust. The final results showed that more than 95% of zinc and 89% of germanium were efficiently recovered, and heavy metals such as arsenic and cadmium were fixed in the liquid, and then concentrated in the purification and impurity removal stage. The residue after reaction is high-grade lead sulfate residue, which can be returned to the lead smelting system for recycling. In summary, the ultrasonic-enhanced ammonium persulfate process eventually makes all substances in germanium-containing dust harmless and resource treatment.
研究领域:
冶金学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Penghai Wei,Yali Zhang,Yaoguo Huang,Yun Jia,Linlin Chen,Ming Wang
Cyanide wastewater contains highly toxic substances such as cyanide and metals. A simple and efficient photoelectro-catalytic oxidation method was proposed. Effect and mechanism of cyanide degradation and Cu/Zn recovery by photoelectro-catalytic oxidation were investigated. The experimental results show the degradation efficiency of total cyanide and removal efficiencies of copper and zinc reached 96.90%, 99.76% and 90.56%, respectively, under the optimum conditions of 2.5 V external bias voltage and 4.0 h with air and lighting. An external electric field can significantly improve the migration and separation of photo-generated electrons ( e – ) and holes ( h + ), thereby increasing the photocatalytic efficiency. Simultaneously, the surface potential of semiconductor is lower than the body under the action of bias voltage and leads to energy band bending. XPS analysis indicates that cyanide is finally degraded into carbon oxide and nitrogen. Cu and Zn are mainly recovered as elementary substance.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Boxiong Zhang,Wenxiong Dong,Yaowu Wang,Xiaomeng Cao,Jianping Peng,Yuezhong Di,Buju Guo,Zhongyu An,Jiaoyang Xia
Alkaline zinc–manganese batteries are the most used disposable batteries in the world and cannot be recharged. Spent alkaline zinc–manganese batteries are mainly disposed of in landfills, and the resulting enrichment of the soil with potassium(K), zinc(Zn), and manganese(Mn) pollutes the groundwater and wastes valuable resources. Herein, a process for the treatment of used alkaline zinc(Zn)–manganese(Mn) batteries that involved water leaching, calcination, and vacuum aluminothermic reduction was developed. Investigation of the elemental migration process and reaction mechanism showed that the purity of potassium carbonate(K 2 CO 3 ) reached 99 % with 92.1 % recovery at a water leaching temperature of 60 °C and time of 25 min. The leaching slag was calcined at 700 °C for 1 h to obtain calcined slag with zinc oxide (ZnO), manganese(III) oxide (Mn 2 O 3 ), and manganese(II) oxide (MnO) as the main phases. When the calcined slag was reduced with aluminum powder, the recovery rate of Zn reached 99.7 % at a reduction temperature of 1100 °C, reduction time of 2 h, and ratio of aluminum powder to calcined slag of 1.5:1. Under these conditions, Mn was recovered in the form of Al 6 Mn alloy, and the main phase of the remaining reduced slag was alumina. In this study, potassium and metallic zinc were separated and recovered, and at the same time, an aluminum(Al)–manganese(Mn) alloy was prepared. The developed environmentally friendly and emission-free process enables the efficient recycling of the valuable resources K, Zn, and Mn, resulting in cleaner battery disposal.
研究领域:
冶金学
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环境工程
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材料科学
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化学工程
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电池技术
✓ 已验证
产品关联
DOI
高影响因子
Journal of Sustainable Metallurgy
·
2022
·Vol. 8
·期 3
·1090-1103
·
IF 3.068
Jin Yonglong,Gao Lihua,He Zhijun,Sun Yujia
An economic and effective strategy synchronously utilizing blast furnace bag dust (BF-BD) and converter-removing dust (C-RD) by carbothermic reduction roasting is reported to achieve separation and recovery of iron and zinc. In this paper, the effect of operating parameters on the recovery rate and remove rate of Fe and Zn from BD and GD was initially studied by synergetic carbothermic roasting reduction. The optimized parameters include a reduction temperature pf 1200 °C, a reduction time of 90 min, a FC/O of 2.0, and a proportion of C-RD/BF-BD of 7:3, and the removal efficiency of Zn and metallization degree of Fe reached 98.35% and 90.58%, respectively. The phase transformation and stepwise reduction behavior of wüstite (ZnO) x (FeO) 1− x , spinel Zn x Fe 1− x Al 2 O 4 , olivine Zn x Fe 2− x SiO 4 , and gehlenite Zn z Fe 2− x SiAl 2 O 7 are systematically investigated by SEM–EDS, XRD, TG/DTG, and thermodynamic analyses. It was found that the formation of wüstite (ZnO) x (FeO) 1− x as an intermediates plays an crucial role in the formation of metallic Zn–Fe–C alloy. Phase transformation and reduction mechanisms of C-RD and BF-BD and the interfacial reaction formation mechanism of wüstite (ZnO) x (FeO) 1− x were discussed and clarified in synergistic carbothermic reduction process. Graphical Abstract
研究领域:
冶金工程
·
材料科学
·
环境工程
✓ 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）