响应曲面法优化废铂催化剂中难溶颗粒HCl-DCEA体系回收工艺

Optimization of recovery process for insoluble particles from waste platinum catalyst by HCl-DCEA system using response surface methodology

全溶解法回收废铂催化剂在实际生产过程中仍有难溶物沉积,造成二次污染及铂族资源浪费。本研究将难溶颗粒进行破碎细磨后,取300目左右粉体焙烧,然后将所得粉体在HCl-DCEA体系中进行浸出,考察反应时间、反应温度、液固比、盐酸浓度及DCEA浓度对铂浸出率的影响,并选择具有显著影响的液固比、盐酸浓度及DCEA浓度因素进行响应曲面优化试验。结果表明,对铂浸出率影响的显著顺序为DCEA浓度>液固比≈盐酸浓度;优化后的工艺条件为浸出时间2 h、浸出温度70℃、液固比6∶1、盐酸浓度2.35 mol/L、DCEA浓度0.09 mol/L,该条件下对废铂催化剂进行回收处理,总回收率达到99.64%。

In the actual production process of recovering waste platinum catalysts using the total dissolution method,there are still insoluble deposits,resulting in secondary pollution and waste of platinum group resources.In this study,insoluble particles were crushed and finely ground,and about 300 mesh powders were calcined.The obtained powders were then leached in the HCl-DCEA system to investigate the effects of reaction time,reaction temperature,liquid-solid ratio,hydrochloric acid concentration,and DCEA concentration on platinum leaching rate.Significant factors such as liquid-solid ratio,hydrochloric acid concentration,and DCEA concentration were selected for response surface optimization experiments.The results indicate that the significant order of influence on platinum leaching rate is DCEA concentration>liquid-solid ratio≈hydrochloric acid concentration;The optimized process conditions are leaching time of 2 hours,leaching temperature of 70℃,liquid-solid ratio of 6:1,hydrochloric acid concentration of 2.35 mol/L,and DCEA concentration of 0.09 mol/L.Under these conditions,the waste platinum catalyst is recovered and treated,with a total recovery rate of 99.64%.