回收废铑催化剂的预处理工艺研究

Pre-treatment process of the recovery of deteriorated rhodium catalyst

通过将定量的废铑催化剂与定量的添加剂在坩埚中均匀混合,在一定的程序升温条件下于电阻炉中进行焚烧,冷却后将焚烧残渣研细得到铑灰,将所得铑灰用盐酸进行溶解制得含铑的水溶液,考察了添加剂种类、添加剂用量、灰化温度、溶解温度、溶解时间和溶剂用量等工艺条件对铑的液相回收率的影响.结果表明:灰化温度和溶解温度对铑的回收率的影响显得尤为明显,较佳的工艺条件为:添加剂为Ca(OH)2,Ca(OH)2添加量为原料量与Ca(OH)2的质量比为1∶1,灰化温度为320℃,溶解温度为35℃,溶解时间为8 h,溶剂用量为6 mL HCl/g铑灰.在上述实验条件下,铑的液相回收率较为理想,可达到96.5%.

Under a particular programmed temperature,the mixture containing the deteriorated rhodium catalyst and additive were combusted and ash-fired in muffle furnace.After cooling,the recovered rhodium ash was dissolved in hydrochloric acid solution.The process conditions including the additive type and amount,ashing temperature,dissolving temperature and time,solvent amount were investigated in detail.The results indicated that ashing temperature and dissolving temperature exhibited great influences on the recovery rate of rhodium.The preferable additive was calcium hydroxide and the optimum mass ratio of rhodium catalyst and calcium hydroxide was determined as 1∶1.Other conditions included the ashing temperature of 320℃,the dissolving temperature of 35℃,the dissolving time is 8 h and the amount of hydrochloric acid of 6 mL per gram of rhodium ash,corresponding to the recovery rate of 96.5%.