亚硝酸甲酯羰基化合成草酸二甲酯废旧催化剂Pd/α-Al2O3中Pd的提取

Extraction of Pd from waste catalyst Pd/α-Al_2O_3 in the synthesis of dimethyl oxalate( DMO) by methyl nitrite carbonylation

采用HCl+H_2O_2混合溶液浸泡废旧催化剂Pd/α-Al_2O_3,滤掉氧化铝球颗粒,加入氨水沉淀滤液中Pd之外的微量杂质并过滤,在滤液中加入丁基钠黄药,形成Pd化合物沉淀,过滤,100℃烘干,350℃焙烧,生成PdO,纯度99. 541%,再用H_2或CO在≥700℃下还原,得到纯Pd。该方法成本低,相对于王水法更环保、高效,Pd回收率> 99. 99%。

Waste catalyst Pd/α-Al2O3 was dipped into the mixture solution of HCl and H2O2,and then filtered to remove Al2O3 particles. NH4OH was added to the filtrate to precipitate impurity except for Pd and filtered secondly. C4H9OOSSNa was added to the filtrate to precipitate Pd and filtered thirdly. The wet filter cake obtained was oven-dried at 100 ℃,and then calcined in air at 350 ℃ to get PdO with purity of 99. 541%. PdO was reduced by H2 or CO at temperature above 700 ℃. This method with Pd recovery higher than 99. 99% shows lower cost,better for environmental protection and higher efficient comparing with aqua rejia method.