Study on continuous liquid phase oxidation of toluene in microchannel reactor
ZHANG Yue1,2, ZHANG Yong-chao1,2, YAN Sheng-hu1,2, LIU Jian-wu1,2, SHEN Jie-fa1,2, CHEN Dai-xiang1,2, SHEN Yu-fan2
1. Institute of Flow Chemistry & Process Engineering, Changzhou University, Changzhou 213164, China; 2. School of Pharmaceutical Engineering & Life Science, Changzhou University, Changzhou 213164, China
Abstract: Benzaldehyde is synthesized through liquid-phase oxidation method in a pulsed microchannel reactor with toluene as substrate,cobalt acetate as catalyst,sodium bromide as initiator and peracetic acid as liquid phase oxidant.The effects of raw materials ratio,residence time,reaction temperature,adding amount of catalyst and initiator and solvent amount on the reaction are investigated.The results show that the conversion rate of toluene can reach 30.8% and the selectivity of benzaldehyde can be 83.5% when n(toluene):n(peroxyacetic acid)=1:3,V(toluene):V(acetic acid)=1:5,n (cobalt acetate):n(toluene)=1:75,n(sodium bromide):n(toluene)=1:30,the reaction temperature remains at 110℃ and the residence time is 10 min.Compared with the traditional batch reaction process,the microchannel reactor can strengthen mass transfer and heat transfer during the reaction process,which can greatly enhance the reaction rate and the utilization rate of raw materials,expand the selection range of process conditions and realize effective control on the oxidation reaction process.
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