乙醇缩合制高碳醇(C_(6+)醇)多相催化剂研究进展

Progress in heterogeneous catalyst for ethanol upgrading to higher(C_(6+)) alcohols

以乙醇为原料制备其他高附加值化工产品近期得到了广泛关注,特别是乙醇基于Guerbet反应缩合制备高碳醇(C_(6+))的过程更成为这一领域的研究热点。本文着重报道了近年来乙醇转化为高碳醇过程的几种典型的多相催化剂,包括羟基磷灰石(HAP)、类水滑石(LDHs)以及各种负载型金属催化剂的研究开发现状,分析比较了各类催化剂的优势与不足,结合反应机理针对催化剂对高碳醇选择性不高的原因进行了讨论,对理想催化剂的设计和改进进行了展望,指出应该通过促进Guerbet反应中的羟醛缩合过程增加高碳醇的选择性。金属负载型催化剂对该反应控制步骤的加速作用显著,而金属位点和载体表面酸碱活性位点的精细调控以及特定催化剂形貌结构的控制合成则是该领域未来的研究重点。

Conversion of ethanol to other high value-added chemicals has attracted extensive attention recently,especially upgrading to higher alcohols(C_(6+))through Guerbet reaction.The research and development status of several typical heterogeneous catalysts,including hydroxyapatite(HAP),hydrotalcite(LDHs)and supported metal catalysts,for the conversion of ethanol to higher alcohols in recent years are reviewed in this paper.Their advantages and disadvantages are comprehensively compared and analyzed.The reasons for the low selectivity for higher alcohols of current catalysts are discussed based on the reaction mechanism.The design and improvement to obtain an ideal catalyst are prospected.It is pointed out that the higher alcohols selectivity could be improved by promoting the aldol reaction step in Guerbet reaction.The metal-supported catalyst can accelerate the rate-limiting step significantly.Fine regulation of metal,acid and base active sites distribution on the support surface and the controlled synthesis of catalyst with specific structures will be the focus of future research in this field.