废SCR催化剂中钒和钨的有机酸浸出

在对废SCR催化剂组成进行分析的基础上,采用草酸和酒石酸两种有机酸浸取废SCR催化剂中的V和W。实验结果表明：草酸对V、W的浸出率均大于酒石酸;在草酸浓度为1.00 mol/L、浸取温度为80 ℃、液固比为10 mL/g、浸取时间为180 min时,V和W的浸出率分别为63.50%和13.12%;在酒石酸浓度为0.5 mol/L、浸取温度为100 ℃、液固比为10 mL/g、浸取时间为180 min时,V和W的浸出率分别为44.00%和9.00%。酸性浸出未改变SCR催化剂中TiO₂的晶型,剩余残渣中依然保留着TiO₂骨架,可继续作为催化剂载体使用。

Selective leaching of vanadium and tungsten from spent SCR catalyst using organic acids

Based on composition analysis of spent SCR catalyst,two organic acids,oxalic acid and tartaric acid were chosen to leach V and W from the spent catalyst. The experimental results show that：The leaching rate of V and W by using oxalic acid is higher than that by using tartaric acid;For oxalic acid leaching system,when the oxalic acid concentration is 1.00 mol/L,the leaching temperature is 80 ℃,the liquid-solid ratio is 10 mL/g and the leaching time is 180 min,the leaching rate of V and W is 63.50% and 13.12%,respectively;For tartaric acid leaching system,when the acid concentration is 0.5 mol/L,the leaching temperature is 100 ℃,the liquid-solid ratio is 10 mL/g and the leaching time is 180 min,the leaching rate of V and W is 44.00% and 9.00%,respectively. The crystal form of TiO₂ in SCR catalyst is not changed by acid leaching and the anatase TiO₂ is remained in the leaching solid residue which can be recovered as catalyst carrier.