Study on Kinetics of Hydrogenation of CBDK to CBDO
YOU Wentao1, YANG Lei2, WANG Chengxiang2, PAN Teng1, CHENG Youwei1, LI Xi1,2
1.College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China;
2.Zhejiang Hengyi Research Center, Hangzhou 310019, China
Abstract 2,2,4,4-tetramethyl-1,3-cyclobutanediol (CBDO) is an important monomer for preparing high-performance polyesters. Hydrogenation of 2,2,4,4-tetramethyl-1,3-cyclobutanedione (CBDK) to CBDO is the core reaction of its preparation process. The kinetics of CBDK hydrogenation over Ru/C catalyst was studied in a stirred tank reactor. Through high resolution transmission electron microscope (HRTEM), observation on the micro morphology of the catalyst revealed that Ru was uniformly distributed on the surface with average particle diameter around 2-3 nm, which can enhance the hydrogenation activity and selectivity. The effect of catalyst mass, temperature and pressure on the hydrogenation reaction were investigated with mass transfer influences eliminated. The results showed that the reaction was a series reaction. CBDK was rapidly hydrogenated to produce 2,2,4,4-tetramethyl-1,3-cyclobutanol ketone (CBKO) and then further hydrogenated to produce CBDO. Langmuir-Hinshelwood-Hougen-Watson (LHHW) kinetic model based on hydrogen molecular state adsorption and surface reaction being the rate limitation gave the best fitting. There was competitive adsorption of CBDK, CBKO and CBDO on the active site of the catalyst, and the adsorption equilibrium constants were 951.9, 280.1 and 60.0 L/mol, respectively. Activation energy of each step were 34.7 kJ/mol and 47.9 kJ/mol, respectively. The results can provide guidance for the design and optimization of the reactor of CBDK hydrogenation.
YOU Wentao,YANG Lei,WANG Chengxiang et al. Study on Kinetics of Hydrogenation of CBDK to CBDO[J]. Chemical Reaction Engineering and Technology, 2022, 38(1): 1-11.
YOU Wentao,YANG Lei,WANG Chengxiang et al. Study on Kinetics of Hydrogenation of CBDK to CBDO[J]. Chemical Reaction Engineering and Technology, 2022, 38(1): 1-11.
