GREEN CHEMISTRY
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2024
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IF 9.3
Hongya Wang,Fengyin Zhou,Bingbing Wang,Muya Cai,Jingjing Zhao,Xinyu Li,Yongxin Wu,Xiaowei Liu,Xiang Chen,Dihua Wang,Huayi Yin
The sulfur transfer is key to obtaining greenness of recycling spent lead paste (SLP) since conventional recycling methods always involve generating secondary wastes such as sulfur oxides (SOx), sulfates, and sulfides. To address these challenges, we propose a combined process in which the SLP is first converted into lead sulfide (PbS) by carbothermic reduction, and then the resultant PbS is split into liquid lead (Pb) and sulfur vapor (Sx) by molten salt electrolysis (MSE). The faradaic efficiency of MSE reaches 92.29% with a Pb recovery rate of 97.85%, and the liquid Pb and gaseous Sx are respectively discharged from the bottom and top of the cell to allow the reaction to happen continuously. Compared with traditional methods, over 98.85% of SO2 emissions are reduced, and no sulfides and sulfates are generated. Furthermore, the energy consumption is only 0.32 kW h (kg-Pb)−1, which demonstrates a 67% reduction compared to mainstream recycling processes using a 50 g-scale electrolyzer. Overall, we offer a clean sulfur transfer route to reduce secondary wastes and energy consumption, which will benefit the recovery and utilization of various sulfate wastes and raw materials with low environmental footprints.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
JOM
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2020
·Vol. 72
·期 9
·3195-3203
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IF 2.054
Xie Boyi,Yang Tianzu,Liu Weifeng,Zhang Duchao,Chen Lin
The treatment of spent lead paste is essential for the recycling of spent lead-acid batteries. In this study, we propose a facile route for the recovery of lead from spent lead paste by pre-desulfurization followed by low-temperature reduction smelting. The effects of two desulfurization methods, i.e., high-pressure and normal-pressure processes, on the desulfurization efficiency of spent lead paste were compared. The high-pressure process was found to be more effective than the normal-pressure process; 99.1% of sulfur was removed under the high pressure conditions with NaOH excess of 1.1 at 150°C for 30 min. Moreover, a part of PbO 2 reacted with PbO to form Pb 3 O 4 . Afterwards, the desulfurized residue, mainly consisting of Pb 3 O 4 and PbO 2 , was directly used in low-temperature reduction smelting, and the optimum smelting conditions were determined to be: starch/Pb-residue mass ratio = 1/6.3; Na 2 O/Pb-residue mass ratio = 1/15; B 2 O 3 /Pb-residue mass ratio = 1/7.5; smelting temperature 700°C; and smelting duration 90 min. The lead recovery under the optimum conditions was as high as 93%. Scanning electron microscope images of the smelting slag showed that the smelting slag mainly consisted of PbO x and Na 2 O.
研究领域:
环境科学
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冶金工程
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产品关联
DOI
高影响因子
Journal of Sustainable Metallurgy
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2024
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IF 2.5
Yang Yi,Ouyang Lun-ao,He Yapeng,He Puqiang,Tu Jian,Huang Hui,Guo Zhongcheng
The hydrometallurgical recycling of spent lead-acid battery has received extensive attention benefitting from its features of cleanability and process controllability, but the process still suffers from significant challenges of huge chemical consumption and low economic efficiency. Here, a sustainable green approach that enables closed-loop recovery of leaching reagent NH 4 Ac to obtain high-purity PbO powder from discarded lead paste is proposed. The process includes dissolution, chemical transformation, carbonization, and calcination stages. Under the optimal leaching condition of NH 4 Ac concentration 4.5 mol L –1 , H 2 O 2 /PbO 2 molar ratio 1.5, reaction temperature 40 °C, and time 60 min, the leaching ratio of lead reaches as high as 99.35%. The exceptionally high concentration of NH 4 Ac to dissolve PbSO 4 phases than theoretical ratio could be attributed to the distribution state of Pb substances. With (NH 4 ) 2 CO 3 as carbonizing agent, above 99.9% of lead could be precipitated as PbCO 3 products when the molar ratio CO 3 2– /Pb is 1.2. High-purity β-PbO powder is subsequently achieved from the thermal decomposition of PbCO 3 precursor, where the effect of calcination temperature and atmosphere on the chemical compositions are examined. Economic analysis reveals the economic feasibility and profits of the recycling approach. The process produces high-purity PbCO 3 and PbO products enabling leaching reagents NH 4 Ac reuse, providing a practicable solution for sustainable recovery of lead from waste lead paste. Graphical
研究领域:
环境科学
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冶金工程
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2019
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IF 5.107
Tianzu Yang,Boyi Xie,Weifeng Liu,Duchao Zhang,Lin Chen
Spent lead paste, an important secondary resource, calls for recycling at the request of both environmental protection and the sustainable development of lead industry. An environment-friendly process to recover lead from spent lead paste was proposed. The impurities Sb, Ca, Fe and Cu in spent lead paste were firstly removed by H 2 SO 4 at the leaching rate of 92.22%, 86.43%, 87.89% and 94.04%, respectively. And then, 99.9% of PbO 2 in spent lead paste was reduced to PbO by the hydrothermal reduction process with glucose as the reductant. In the process of hydrothermal desulfurization by NaOH, 99.46% of S in the reduced lead paste was removed and then the lead paste was converted into a single phase of 3PbO·H 2 O. Finally, metallic lead, with a purity of 99.978%, was obtained from the single-phase lead paste by a low-temperature reduction smelting process with starch as the reductant under the conditions of Na 2 O/B 2 O 3 = 1/2, PbO/B 2 O 3 = 5/1, starch/PbO = 1/7.5, smelting temperature 700 °C, and smelting duration 90 min, and the lead recovery is high up to 95.53%. Compared with the traditional lead smelting technology, the smelting temperature was reduced from 1200 °C to 700 °C, helping greatly reduce the energy consumption. The process proposed in this paper guides a new development direction for the utilization of spent lead paste.
研究领域:
冶金工程
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环境科学
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DOI
高影响因子
RSC Advances
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2015
·Vol. 5
·期 115
·94895-94902
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IF 3.84
Cheng Ma,Yuehong Shu,Hongyu Chen
A sustainable method, with minimal pollution and low energy cost in comparison with the conventional smelting method, is proposed for treating components of spent lead acid batteries with oxalate and sodium oxalate. The pure lead oxalate precursor of PbC2O4 is the only product crystallized in the leaching experiment. Lead oxalate is readily crystallized from the solution due to its low solubility and can be combusted to directly produce lead oxide as a precursor for making new battery pastes. Both lead oxalate and the oxide products have been characterized by means of thermogravimetric analysis (TGA) and X-ray diffraction (XRD). The results show that the lead oxides synthesized at different calcination temperatures are comprise of α-PbO and β-PbO. The batteries assembled using the novel lead oxide powder as the positive active material show good cyclic stability for 50 charge/discharge cycles. The cell using lead oxide powder containing 15 wt% β-PbO exhibits excellent initial capacity, cycling performance and high-rate discharge characteristics and can deliver a discharge capacity of 180 mA h g−1 at 30 mA g−1 and more than 60 mA h g−1 at 240 mA g−1. Within 50 cycles, its capacity loss is low (5%) with excellent cyclic stability.
研究领域:
环境科学
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材料科学
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化学工程
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能源技术
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可持续发展
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电化学
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资源循环利用
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）