Study On Gas-liquid-liquid Catalytic Oxidation Network And Kinetics Of The Synthesis Of 2,3,5-Trimethy-1,4-benzoquinone

2,3,5-Trimethyl-1,4-benzoquinone (TMQ) is an important intermediate for the synthesis of vitamin E. TMQ was commercially produced by gas-liquid-liquid oxidation of 2,3,6-trimethylphenol (TMP). The gas-liquid-liquid oxidation of TMP was studied in this thesis with aqueous solution of CuCl2 and FeCl3 as catalyst aqueous phase, solution of TMP in hexanol as oil phase and oxygen as oxidant. The effects of operation parameters, reaction time, reaction temperature, the amount and composition of the catalyst, the ratio of aqueous phase to oil phase and the oxygen flow rate were researched. The reaction network was obtained, the reaction mechanism was proposed and the kinetics model of the oxidation from TMP to TMQ is established, which could provide theoretical guidance for deep understanding gas-liquid-liquid oxidation and enhancing commercial yield.GC-MS and HPLC-MS were used to characterize the products structure and GC was used to track and analyze the reaction process. The results showed that many intermediates and byproducts,4-Chloro-2,3,6-trimethylphenol,2,3,5-Trimethyl-1,4--benzeediol,2,3,6-Trimethyl-4-(2,3,6-trimethylphenoxy)phenol, and 2,2’,3,3’,5,5’--hexamethyl-4,4’-bisphenol were formed. And Cl-TMP, PP and TMHQ were intermediate products because they would react further. Therefore, the reaction network was proposed as follows:Hatta numbers were obtained by calculating and estimating the parameters of the reaction process and Ha numbers were between 0.3 and 3, which means the kinetics of gas-liquid-liquid oxidation of TMP was in macro-kinetics regime including mass transfer.When the aqueous phase fraction was 0.3 and the amount of catalyst was small, TMHQ and PP were less than 1% and can be neglected, the main product TMQ, byproduct BP and the intermediate Cl-TMP were in the majority. The corresponding reaction kinetics parameters were obtained based on the established kinetics model with matlab by using genetic algorithm and Runge-Kutta method. The average deviation between calculated and measured data was 2.89%.