Esters hydrogenolysis over CuZn catalysts was shown to be accompanied by transesterification lowering the yield of the desired alcohol. Here we investigate the origin of the transesterification activity by studying Cu, Zn and CuZn based catalysts in transesterification of dimethyl adipate (DMA) with hexane-1,6-diol (HDO). The experiments were performed at conditions relevant for hydrogenolysis, i.e. 210 °C and 10–70 bar of either N₂ or H₂ atmosphere. Although transterification was found to be catalysed by acid impurities present in DMA, the main formation of the transesterification products was due to the ZnO phase in the studied catalysts. In contrast, Cu or CuO phase were virtually inactive in transesterification. Moreover, it was shown that the reduced Cu-ZnO catalyst was stable under reaction conditions whereas its oxide form CuO-ZnO underwent leaching. The obtained catalytic data also evidenced that the transesterification products were important reaction intermediates in the formation of HDO.

在CuZn催化剂上的酯氢解显示伴随着酯交换反应，降低了所需醇的产率。在这里，我们通过研究基于铜，锌和铜锌的催化剂在己二酸二甲酯（DMA）与己烷1,6-二醇（HDO）的酯交换中研究酯交换活性的起源。实验是在与氢解有关的条件下进行的，即210°C和10–70 bar的N ₂或H ₂大气层。尽管发现酯化反应是由DMA中存在的酸性杂质催化的，但酯交换产物的主要形成是由于所研究催化剂中的ZnO相。相反，Cu或CuO相实际上在酯交换反应中没有活性。此外，已表明还原的Cu-ZnO催化剂在反应条件下是稳定的，而其氧化物形式的CuO-ZnO经历了浸出。获得的催化数据也证明酯交换产物是HDO形成中的重要反应中间体。