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采用表面反应改性法制备了ZrO2 SiO2 (ZrSiO)表面复合物 ,用等体积浸渍法制备了ZrSiO担载的Cu Ni双金属催化剂 ,并用IR ,TPD ,TPSR和微反技术考察了CO2 和CH3 OH在催化剂表面上的化学吸附及反应性能 .实验结果表明 :在Cu Ni/ZrSiO催化剂上存在着Cu Ni金属位M ,Lewis酸位Zrn + 和Lewis碱位Zr O-三类活性中心 ;CO2 在金属位和Lewis酸位的协同作用下可形成CO2 卧式吸附态 ,此吸附态在 142℃左右可解离成M CO和Zr O-;CH3 OH在Lewis酸位和Lewis碱位的协同作用下可形成解离吸附态Zr OCH3 和Zr OH ;CO2 和CH3 OH在Cu Ni/ZrSiO催化剂表面上的主要反应产物为碳酸二甲酯 (选择性在 85 %以上 ) ,另有少量的CH2 O ,CO和H2 O .
ZrO2 SiO2 (ZrSiO) surface composites were prepared by the surface reaction modification method. The ZrSiO supported Cu Ni bimetallic catalysts were prepared by the same volume impregnation method. The effects of CO2 and CH3 OH on the surface were investigated by IR, TPD, TPSR and micro- The results show that Cu Ni metal sites M, Lewis acid sites Zrn + and Lewis basic sites Zr-O exist in Cu Ni / ZrSiO catalysts. Under the synergistic action of Lewis acid site and Lewis acid site, the CO2 horizontal adsorption state can be formed. The adsorption state can be dissociated into M CO and Zr O- at about 142 ℃. The synergistic effect of CH3 OH between Lewis acid sites and Lewis bases The main reaction products of CO2 and CH3OH on the surface of Cu Ni / ZrSiO catalyst were dimethyl carbonate (selectivity is more than 85%), and a small amount of CH2 O, CO and H2 O.