以柠檬酸为主要浸出剂,在室温下合成柠檬酸铅前躯体,将其低温焙烧生成超细PbO/Pb粉末。结果表明:废旧铅蓄电池铅膏的主要成分PbO2、PbO和PbSO4都能生成柠檬酸铅,铅回收率均在98%以上;由PbO与PbO2生成的前躯体与标准柠檬酸铅晶型基本相同,结构呈堆积条状,粒径为20~30μm,而由PbSO4得到的前躯体可能含较多结晶水,与标准柠檬酸铅晶型有较大区别,呈鳞片状结构,粒径为1~10gm;3种前躯体都能在低温焙烧下得到超细PbO/Pb粉末,粒径为200~500nm;采用柠檬酸湿法浸取铅膏直接制备电池生产用超细PbO粉体的新工艺,为废旧铅酸电池的回收技术提供了一种新的思路。
The lead citrate precursors were prepared at room temperature with citric acid as the main leaching agent combined with other additives such as sodium citrate and H2O2. The ultrafine lead oxide powder was prepared from the precursors at low temperatures. The results show that the lead pastes can be leached, and crystallized lead citrate precursors are obtained. The rate of conversion of lead is above 98%. The crystalline structures of the lead citrate precursors from lead oxide and lead dioxide match well with the standard citric lead, and the size of the precursors are 20-30μm. However, there is difference between the structures of the lead citrate precursors from PbSO4 and the standard citric acid-lead crystal, which can be caused by the more crystal water in the structure of the lead citrate precursors from PbSO4. The precursors are columnar structures with size of 1-10 ~tm. The ultra-fine PbO/Pb powders, with the size of 200-500 nm, are prepared from three lead citrate precursors at low temperatures. The study indicates a feasible method to prepare ultrafine lead oxide powder from spent lead battery.