Mechanism and kinetics of 1-phenyl-1,2-ethanediol cleavage catalyzed by Cu/Beta zeolite

To explore the feasibility of producing high-value products from biomass, the copper-supported off-Al H-Beta zeolite was prepared and used as a catalyst. The 1-phenyl-1,2-ethanediol was chosen as a catalyst, a model molecule of biomass, the reaction mechanism and reaction path of the oxidative cleavage were studied. The variation of concentration for different components and products distribution were obtained under different temperatures. Based on these experimental results, a kinetic model of the reaction system was established, and the kinetic parameters were developed through optimization algorithms. Results show that Brønsted acid and Lewis acid have a synergistic role in the oxidative cleavage of 1,2-diol. The adding of Cu species can regulate the acidity and acid amount of the catalyst and can effectively improve the C─C bond breaking ability of the catalyst. 1-phenyl-1,2-ethanediol firstly underwent oxidative cleavage to produce benzaldehyde, which further underwent parallel tandem reactions to get benzyl alcohol (BP), methyl benzoate (MB), and benzaldehyde dimethyl acetal (BDA), respectively. The highest activation energy is required for the oxidative cleavage reaction in the reaction system, and a higher temperature thus will be needed.