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 nitr...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.展开更多
基金Financial support from the Natural Science Foundation of China(Nos.20936003,21325626,21176179)the Specialized Research Fund for the Doctoral Program of Higher Education(SRFDP)(No.20090032110021)
文摘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.
