Xiao Han, Zhang Chao, Zhao Jiaojiao, Zheng Zhaohui, Li Yuehui
School of Chemical Engineering, Guizhou Minzu University Guiyang 550025 P. R. China.
State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics (LICP), Chinese Academy of Sciences Lanzhou 730000 P. R. China
RSC Adv. 2023 May 31;13(24):16363-16368. doi: 10.1039/d3ra02223d. eCollection 2023 May 30.
Selective hydrogenation of dimethyl terephthalate (DMT) is an ideal way to prepare 1,4-cyclohexane dicarboxylate (DMCD), an important intermediate and monomer. Even though noble metal-based catalysts (, Ru, Pd) have been developed for selective hydrogenation of DMT, the use of non-precious Ni catalysts to achieve high activity and selectivity is still challenging. In this study, we present that only 0.5 wt% of KF by post-impregnated doping can significantly improve the performance of Ni/SiO catalysts (83% 96% selectivity; 41% 95% conversion). The selectivity of DMCD can be up to 97%, which is the highest reported over Ni catalysts. The boosting effect of KF modification might be due to higher amounts of Ni(0) species and lower amounts of moderate acidic sites, which are beneficial for selective hydrogenation of phenyl rings over hydrogenolysis of ester groups.
对苯二甲酸二甲酯（DMT）的选择性加氢是制备1,4 - 环己烷二甲酸酯（DMCD）的理想方法，DMCD是一种重要的中间体和单体。尽管已经开发出用于DMT选择性加氢的贵金属基催化剂（如Ru、Pd），但使用非贵金属Ni催化剂实现高活性和选择性仍然具有挑战性。在本研究中，我们发现通过后浸渍掺杂仅0.5 wt%的KF就能显著提高Ni/SiO催化剂的性能（选择性为83% - 96%；转化率为41% - 95%）。DMCD的选择性可达97%，这是在Ni催化剂上报道的最高值。KF改性的促进作用可能是由于较高含量的Ni(0)物种和较低含量的中等酸性位点，这有利于苯环的选择性加氢而非酯基的氢解。
