燕麦秸秆酸浸回收废旧锂电池中Co的动力学

Kinetics of acid leaching cobalt from waste lithium-ion batteries using oat straw

以生物质燕麦秸秆粉为还原剂,在硫酸条件下酸浸回收废旧锂电池中的Co,并对其浸出过程进行动力学研究。结果表明:0~20 min酸浸Co的过程为反应核收缩模型,表观活化能为27.5 k J/mol;30~150 min(低于80℃)Co的浸出过程也符合反应核收缩模型,表观活化能为28.32 k J/mol,受扩散和化学反应混合控制,其中又以化学反应控制为主。在液固比为10 m L/g,单位质量电池渣所用麦秆粉量0.7 g、硫酸浓度2 mol/L、温度90℃、反应时间2 h的条件下,电池粉中Co的浸出率达到99%以上。

The oat straw biomass was used as reducing agent to leach cobalt from waste lithium-ion battery under the condition of sulfuric acid. The kinetics of the leaching process was researched. The results show that the leaching process fits the reacted shrinking core model within the first 20 min, the apparent activation energy is 27.5 kJ/mol. This conclusion also suits to the second stage (below 80 ℃), namely during 30?150 min, the apparent activation energy is 28.32 kJ/mol, and this process is controlled by diffusion and chemical reaction, in addition, the latter one is dominated. When the liquid-solid ratio is 10 mL/g, the amount of oat straw biomass is 0.7 g per gram battery powder, the concentration of H2SO4 is 2 mol/L, and the temperature is 90℃, reacting time is 2 h, the leaching rate of cobalt in the battery powder is more than 99%.