Selective hydrogenation of dimethyl terephthalate over a potassium-modified Ni/SiO2 catalyst

Han Xiao; Chao Zhang; Jiaojiao Zhao; Zhaohui Zheng; Yuehui Li

doi:10.1039/d3ra02223d

Selective hydrogenation of dimethyl terephthalate over a potassium-modified Ni/SiO₂ catalyst

RSC Adv. 2023 May 31;13(24):16363-16368. doi: 10.1039/d3ra02223d. eCollection 2023 May 30.

Authors

Han Xiao¹, Chao Zhang¹, Jiaojiao Zhao², Zhaohui Zheng³, Yuehui Li²

Affiliations

¹ School of Chemical Engineering, Guizhou Minzu University Guiyang 550025 P. R. China.
² State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics (LICP), Chinese Academy of Sciences Lanzhou 730000 P. R. China yhli@licp.cas.cn.
³ College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology Qingdao 266000 P. R. China.

Abstract

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 (e.g., 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/SiO₂ catalysts (83% vs. 96% selectivity; 41% vs. 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.