The deactivation-regeneration of catalyst PdCl2-CuCl2-KOAc/AC in the synthesis of dimethyl carbonate （DMC） by gas-phase oxidative carbonylation was studied on the basis of XPS characterization and activity evaluatio...The deactivation-regeneration of catalyst PdCl2-CuCl2-KOAc/AC in the synthesis of dimethyl carbonate （DMC） by gas-phase oxidative carbonylation was studied on the basis of XPS characterization and activity evaluation.The reason for the catalyst deactivation is the loss of chlorine.The activity and stability of the fresh catalyst pretreated with methanol solution of methyl chloroacetate increases greatly.If the deactivated catalyst is treated with methanol solution of methyl chloroacetate and in N2 stream successively, the catalytic activity can be restored effectively and the regeneration induction period can be shortened.The catalytic activity after regeneration tiwice can still be restored to 93% of the fresh catalyst.展开更多
在 2 0钢气相渗碳时对比了渗剂中加入 Ce O2 或不加 Ce O2 时的渗碳动力学 ,发现在渗剂中加入 Ce O2可以显著加快渗碳速率。稀土催渗剂的效果在 85 0℃和 910℃基本相同。认为 Ce O2 加速渗碳的机制是催化。冶炼时在钢中加入的稀土对渗...在 2 0钢气相渗碳时对比了渗剂中加入 Ce O2 或不加 Ce O2 时的渗碳动力学 ,发现在渗剂中加入 Ce O2可以显著加快渗碳速率。稀土催渗剂的效果在 85 0℃和 910℃基本相同。认为 Ce O2 加速渗碳的机制是催化。冶炼时在钢中加入的稀土对渗碳也起加速作用 ,但作用小于渗剂中的稀土。展开更多
文摘The deactivation-regeneration of catalyst PdCl2-CuCl2-KOAc/AC in the synthesis of dimethyl carbonate （DMC） by gas-phase oxidative carbonylation was studied on the basis of XPS characterization and activity evaluation.The reason for the catalyst deactivation is the loss of chlorine.The activity and stability of the fresh catalyst pretreated with methanol solution of methyl chloroacetate increases greatly.If the deactivated catalyst is treated with methanol solution of methyl chloroacetate and in N2 stream successively, the catalytic activity can be restored effectively and the regeneration induction period can be shortened.The catalytic activity after regeneration tiwice can still be restored to 93% of the fresh catalyst.
文摘在 2 0钢气相渗碳时对比了渗剂中加入 Ce O2 或不加 Ce O2 时的渗碳动力学 ,发现在渗剂中加入 Ce O2可以显著加快渗碳速率。稀土催渗剂的效果在 85 0℃和 910℃基本相同。认为 Ce O2 加速渗碳的机制是催化。冶炼时在钢中加入的稀土对渗碳也起加速作用 ,但作用小于渗剂中的稀土。
