The effect of potassium （K） promoter on the catalytic performance of activated carbon （AC） supported Wacker-type catalysts （PdCl2-CuCl2/AC） for the synthesis of dimethyl carbonate （DMC） from CO and methyl nitrite （MN） was investigated by means of N2 adsorption, H2-temperature-programmed reduction （H2-TPR）, and X-ray photoelectron spectroscopy （XPS）. The experimental results showed that the space time yield of DMC on Wacker-type catalysts with different K promoters ranked in the following order： KCI 〉 KOH 〉 CH3COOK 〉 K2CO3. Especially, the addition of KCI significantly improved the catalytic activities of PdCl2-CuCl2/AC catalyst for DMC synthesis from CO and MN. N2 adsorption data indicated that the addition of K promoters did not change the textural properties of Wacker-type catalysts greatly. H2-TPR and XPS results demonstrated that the existence of KCI promoted the reducibility of Cu2＋ species and increased the proportion of Cu2＋ species on catalyst surface, which is favorable for oxidizing Pd0 to active Pd2＋. Further, the addition of KCI benefited the reactivity of PdCI2- CuCl2/AC catalwt for DMC synthesis from CO and MN.
Sheng-Ping WangWei LiYuan-Yuan DongYu-Jun ZhaoXin-Bin Ma
