Ester is an important chemical intermediate, which is usually oxidized by aldehyde or alcohol to prepare acids or derivatives of acids, and ester is prepared by esterification, but the conventional process is complicated, and the energy consumption is very high. How to produce esters efficiently and clean is a common problem to be solved urgently in the industrial synthesis of ester. One-step oxidative esterification of aldehydes with alcohols to esters is a simple, clean and efficient green synthesis method. The activity and lifetime of catalysts are particularly important in this process, which mainly depends on the design and preparation of catalysts. In this work, the recent development of catalysts for oxidative esterification of aldehydes was reviewed. Homogeneous catalysts and heterogeneous catalysts were mainly introduced. In the homogeneous reaction system, the catalyst was not easy to be separated, the price was generally high and had large energy consumption. Therefore, the homogeneous reaction system which was suitable for oxidative esterification was difficult to be industrialized. However, the heterogeneous reaction system had great advantages in industrialization. The catalyst was simple to separate and easily degradable, and can be recycled and reused, but also had problems such as poor stability and low yield. The synthesis, structure and catalytic performance of noble metal catalysts and non-noble metal catalysts for oxidative esterification of aldehydes were analyzed and the reaction mechanism of partial catalysts was summarized. The structure, morphology and specific surface area of the catalysts were adjusted by various preparation methods to expose a large area of the active surface, prolong the service life of the catalyst, and improve the economic efficiency of the catalysts. In addition, the research direction of catalysts for oxidative esterification was prospected. Noble metal catalysts were limited in terms by the cost, no-noble metal catalysts will be the focus of future research for the oxidative esterification of aldehyde with alcohols.
Defeng YIN Yun TIAN Yanxia ZHENG Cuncun ZUO Tingting GE Yuchao LI Haofei HUANG Zhongjun FU
. Research progress on oxidative esterification catalysts[J]. The Chinese Journal of Process Engineering, 2019
, 19(5)
: 932
-939
.
DOI: 10.12034/j.issn.1009-606X.219229