Synthesis of dimethyl carbonate from CO2 and methanol over a hydrophobic Ce/SBA-15 catalyst

Yanfeng Pu; Keng Xuan; Feng Wang; Aixue Li; Ning Zhao; Fukui Xiao

doi:10.1039/c8ra04028a

Synthesis of dimethyl carbonate from CO₂ and methanol over a hydrophobic Ce/SBA-15 catalyst

RSC Adv. 2018 Jul 31;8(48):27216-27226. doi: 10.1039/c8ra04028a. eCollection 2018 Jul 30.

Authors

Yanfeng Pu¹, Keng Xuan^{1

2}, Feng Wang¹, Aixue Li^{1

2}, Ning Zhao¹, Fukui Xiao¹

Affiliations

¹ State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences Taiyuan 030001 PR China zhaoning@sxicc.ac.cn xiaofk@sxicc.ac.cn.
² University of Chinese Academy of Sciences Beijing 100049 PR China.

Abstract

A series of Ce/SBA-15 catalysts with different degrees of hydrophobicities were prepared via a post-grafting method and used for the direct synthesis of dimethyl carbonate (DMC) from CO₂ and methanol. The Ce/SBA-15-6 catalyst exhibited the highest DMC yield of 0.2%, which was close to the equilibrium value under the reaction conditions of 130 °C, 12 h and 12 MPa. The catalysts were characterized via XRD, BET, FT-IR, solid-state ²⁹Si MAS NMR, CA, TEM, XPS and NH₃/CO₂-TPD; the results indicated that the hydrophobicity of the catalysts facilitated the creation of oxygen vacancies, which could act as Lewis acids to activate methanol. Higher amounts of moderate acid sites led to higher yields of DMC. In addition, the hydrophobicity of the catalysts could also reduce the adsorbed water on their surface and increase the DMC yield while shortening the reaction time.