Rapid recovery of high pure PbO from spent lead acid battery without desulfation and chemicals consumption method

• Published in: Waste management (Elmsford) 2024-07, Vol.184, p.52-62
• Main Authors: Chai, Lulu, Li, Tian, Liu, Xiaowei, Dai, Shaozhen, Liu, Xiaoguang, Sun, Yanzhi, Pan, Junqing
• Format: Article
• Language: English
• Subjects: Chiral molecules; Desulfation-free; Dibasic lead sulfate; Intensification process; Spent lead paste recovery
• ISSN: 0956-053X; 1879-2456
• DOI: 10.1016/j.wasman.2024.05.024

Here, we proposed a new ultrafast, low carbon footprint, green recycling high-purity PbO process with histidine+CO2 dual cycles for direct Rotating Liquid Film (RLF) reactor intensification leaching of spent lead paste without desulfation from the perspective of the whole recycling lead chain, which achieves the leaching rate of 99.14% within 60 s, high-purity of PbO (99.99%) and ultra-fine BaSO4 products. [Display omitted] •RLF reactor greatly shortens the leaching time from 40 min to 60 s.•High pure PbO is recovered by multidentate coordination and dissociation strategy.•The proposed histidine + CO2 dual cycles construct a chemical consumption-free method.•The new chemical property of 2PbO·PbSO4 realizes the desulfation-free process. The direct recovery of high-purity PbO from spent lead paste without a pre-desulfation process has significant industrial promise. Herein, we propose a recyclable, ultra-fast, and high value-added closed-loop of high-purity PbO recovery process by intensive multidentate coordination of histidine with crude 2PbO·PbSO4 by a rotating liquid-film (RLF) reactor and CO2 carbonation-dissociation. Parameter optimizations and kinetic calculations show the leaching time is shortened from 40 min to 60 s with 99.14 % leaching rate and 99.99 % PbO purity by internal diffusion control, where the RLF reactor promotes mass transfer and reaction rates by instantly renewing the surface of crude 2PbO·PbSO4. Furthermore, all 5 batches reveal that the separation of SO42− ions from the regenerated mother liquid with Ba(OH)2 significantly improves the recycling rate of the mother liquid and high-purity PbO product. This new strategy reveals a bright prospect of a highly efficient, high value-added, and environmentally friendly recycling route for solid waste resources.