1 Department of Environmental and Municipal Engineering, Henan University of Urban Construction, Pingdingshan, Henan, People's Republic of China.
2 School of Water Conservancy & Environment, Zhengzhou University, Zhengzhou, Henan, People's Republic of China.
Waste Manag Res. 2019 May;37(5):508-515. doi: 10.1177/0734242X19830175. Epub 2019 Feb 26.
In this study, a green recycling process of discarded lead-acid battery paste, which could avoid both the smelting and electro-winning route has been developed. Leaching reagents containing sodium citrate, acetic acid and hydrogen peroxide were reacted with spent lead paste in aqueous media at the pH of 5-6. Lead paste was leached and formed into lead citrate precursor, which was recrystallized and separated from the solution. The optimal conditions for the leaching process at room temperature were found to be the: concentration of acetic acid solution of 0.92 mol L; concentration of sodium citrate solution of 0.478 mol L; initial mass ratio of solid spent lead paste to liquid (solid/liquid ratio) of 1/5 g/mL; and reaction time of 2 hours. The results showed that the desulphurization efficiency of lead paste was up to 99.9%. The optimal conditions for lead citrate re-crystallization from the leaching mixed solution were found to be the re-crystallization temperature of 55C for 5 hours in a water bath. The lead citrate precursor synthesized from discarded lead-acid battery pastes was the chemical formula of Pb(CHO)·3HO with columnar shape in the length of 30-50 μm, which was easily separated from the leaching solution. The results of kilogram-scale experiments made progress easier for obtaining the ultrafine lead oxide product (PbO and Pb) from discarded lead-acid battery paste.
在这项研究中，开发了一种废弃铅酸电池糊状物的绿色回收工艺，该工艺可以避免熔炼和电解两种方法。含有柠檬酸钠、乙酸和过氧化氢的浸出试剂在 pH 值为 5-6 的水介质中与废铅膏反应。铅膏被浸出并形成柠檬酸铅前体，然后从溶液中重结晶和分离。在室温下浸出过程的最佳条件被发现是：乙酸溶液浓度为 0.92 mol/L；柠檬酸钠溶液浓度为 0.478 mol/L；固废铅膏与液体的初始质量比（固液比）为 1/5 g/mL；反应时间为 2 小时。结果表明，铅膏的脱硫效率高达 99.9%。从浸出混合溶液中重结晶柠檬酸铅的最佳条件被发现是在 55°C 的水浴中重结晶 5 小时。从废弃铅酸电池糊状物合成的柠檬酸铅前驱体的化学式为 Pb(CHO)·3HO，呈 30-50μm 长的柱状，易于从浸出溶液中分离。公斤级实验的结果为从废弃铅酸电池糊状物中获得超细氧化铅产品（PbO 和 Pb）提供了更大的进展。
