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报道了双功能Cu( Ⅰ)/ 沸石羰基化催化剂的制备及其FTIR 和XPS表征结果. 催化剂兼具酸性和金属羰基两类活性中心,能够在较温和的条件( ~523 K, 常压) 下催化醇与CO的羰基化合成反应. 以异丁醇为原料时,其C5 羧酸和异戊酸异丁酯的总收率可达20-4 % . 催化剂的XPS和IR表征结果证实,铜以Cu( Ⅰ) 价态存在,吸附CO后,形成金属羰基活性中心Cu(CO) +2 . 可能的反应机理是: 母体沸石Hβ或HZSM5 中的酸性中心使醇质子化,形成碳正离子,随后邻近的金属羰基中心Cu(CO)+2 提供CO, 协同催化使之生成羧酸或最后转变为羧酸酯.
The preparation of bifunctional Cu (Ⅰ) / zeolite carbonylation catalysts and their FTIR and XPS characterization results were reported. The catalyst combines both acidic and metal carbonyl active centers to catalyze the carbonylation of alcohols with CO under milder conditions (~ 523 K, atmospheric pressure). With isobutanol as raw material, the total yield of C5 carboxylic acid and isobutyl isovalerate can reach 20-4%. XPS and IR characterization of the catalyst confirmed that copper exists in the valence state of Cu (Ⅰ) and forms a metal carbonyl active site Cu (CO) +2 after adsorbing CO. The possible reaction mechanism is: protonation of the alcohol in the acidic center of the parent zeolite Hβ or HZSM-5 to form a carbenium ion, followed by the contiguous metal carbonyl center Cu (CO) +2 to provide CO, synergistically catalyzed to carboxylic acid or finally Into a carboxylic acid ester.