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绪言脂肪族伯醇和仲醇在催化剂酸性中心或碱性中心上或者仅在碱性中心上转化成烯烃和羰基化合物或羰基化合物的反应已得到了广泛地研究。脱氢产物(醛或酮)主要在碱性催化剂上形成,而脱水产物,烯烃和醚在酸性点存在时则大量产生。在特定的催化剂上,醇的脱水率以叔、仲、伯的顺序降低,直到羟基分裂形成稳定的碳阳离子。脱氢至脱水产物的反应速率不仅取决于催化剂性质而且取决于反应温度。脱氢反应要克服较高活化能,因此它要在高于脱水反应的温度下进行。
INTRODUCTION The reaction of primary and secondary aliphatic alcohols with conversion to olefins and carbonyl or carbonyl compounds at the acidic or basic center of the catalyst or only at the basic centers has been extensively studied. Dehydrogenation products (aldehydes or ketones) are predominantly formed on basic catalysts, while dehydration products, olefins and ethers are produced in large quantities in the presence of acid sites. On a particular catalyst, the dehydration rate of the alcohol decreases in the tertiary, secondary, and primary order until the hydroxyl group cleaves to form a stable carbocation. The reaction rate of dehydrogenation to dehydration products depends not only on the nature of the catalyst but also on the reaction temperature. Dehydrogenation reaction to overcome the higher activation energy, so it should be higher than the dehydration reaction temperature.