Cu-Zr复合氧化物负载PdO催化氯丙烯醚化合成烯丙基醚

本文采用共沉淀法制备了一系列Cu/Zr比从2/8至9/1的铜-锆复合氧化物,再负载PdO用于氯丙烯与醇醚化反应合成烯丙基醚。PdO/CumZrn催化剂的表征结果证实ZrO2相的存在不仅有益于Pd2+的高分散,同时也能与CuO作用有利于Cu+的生成。PdO/CumZrn催化性能随着Cu/Zr比的增加呈现先增强后减弱的趋势,具有高Cu+含量的PdO/Cu7Zr3催化剂显示出最优性能,反应转化率和选择性分别为53.2%和60.3%。这是因为相比于Cu2+-O2-对,Cu+-Oα-对能够增强醇中-O-H键的解离活化,从而提升了醚化反应。

Synthesis of Allyl Ethers from Allyl Chloride with Alcohols Catalyzed by Copper-Zirconium Oxide supported PdO

A series of copper-zirconium oxides with the Cu/Zr ratio ranging from 2/8 to 9/1 was synthesized by the co-precipitation method. PdO/CumZrn catalysts were prepared and applied to synthesize allyl ethers via the etherification reactions of allyl chloride with alcohols. The characterization results demonstrated that the presence of ZrO2 phase not only can facilitate the high dispersion of Pd2+, but can also favor the formation of Cu+ via the interaction between CuO and ZrO2. The catalytic performance initially increases and then falls off with the progressive increase in the Cu/Zr ratio. The superior performance with a conversion of 53.2% and a selectivity of 60.3% was achieved over the resulting PdO/Cu7Zr3 catalyst with the highest surface molar proportion of Cu+. Good catalytic activity was obtained, because the Cu+-Oα- pairs could enhance the dissociative activation of the -O-H bond in alcohols compared with Cu2+-O2- pairs, subsequently promoting the etherification reactions.