机械化学协同抗坏血酸浸出废旧锂离子电池中的有价金属

利用机械化学活化协同抗坏血酸浸出回收废旧锂离子电池(LIBS)中的金属Co、Li,考察了机械化学活化条件及抗坏血酸的浓度对Co、Li浸出的影响,并对该回收系统的经济性进行分析。结果表明,电池正极材料宜在380℃下预处理30min,以有效去除其中的黏结剂;机械化学活化对金属浸出的提升效果明显,其通过改变正极活性物质(LiCoO2)晶体结构和形貌提升Co、Li的浸出,最佳处理条件为球磨转速650r/m、球磨时间90min、球料比60∶1(质量比)、抗坏血酸摩尔浓度0.26mol/L,在此条件下,Co的浸出率达到98.32%,Li的浸出率达到100.00%。采用机械化学活化协同抗坏血酸浸出可以省去处理过程的溶液加热成本,回收1kg正极活性材料的成本为545.4元,具有一定的经济优势。

Leaching of valuable metals from spent lithium-ion batteries with ascorbic acid via mechanochemical process

Mechanochemical activation and ascorbic acid leaching were used to recover the Co and Li in the spent lithium-ion batteries(LIBS).The effects of mechanochemical activation conditions and the concentration of ascorbic acid on Co and Li leaching were investigated,the economics of the recovery system were also analyzed in the whole process.The results showed that the cathode material should be calcined at 380℃for 30 min to totally remove the binder.The mechanochemical activation had a significant effect on the metal leaching owing to the changes on the crystal structure and morphology of the cathode active material(LiCoO2).The optimum conditions for the leaching of Co and Li were as follows:ball milling speed 650 r/min,ball milling time 90 min,ball-to-mass ratio 60∶1(mass ratio),and concentration of ascorbic acid was 0.26 mol/L.Under this condition,the leaching rate as high as 98.32%for Co and 100.00%for Li.The use of mechanochemical activation with ascorbic acid leaching could avoid the heating cost,545.4 yuan was needed to recover 1 kg cathode material,which had certain economic advantages.