SCI和EI收录∣中国化工学会会刊

中国化学工程学报 ›› 2022, Vol. 50 ›› Issue (10): 222-234.DOI: 10.1016/j.cjche.2022.09.007

• Catalysis, Kinetics and Reaction Engineering • 上一篇    下一篇

Box-Behnken experimental design for optimizing process parameters in carbonate-promoted direct thiophene carboxylation reaction with carbon dioxide

Qingjun Zhang1, Youguang Ma1,2, Xigang Yuan1,2, Aiwu Zeng1,2   

  1. 1 State Key Laboratory of Chemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China;
    2 Chemical Engineering Research Center, Collaborative Innovative Center of Chemical Science and Engineering (Tianjin), Tianjin 300350, China
  • 收稿日期:2022-03-23 修回日期:2022-09-13 出版日期:2022-10-28 发布日期:2023-01-04
  • 通讯作者: Aiwu Zeng,E-mail:awzeng@tju.edu.cn

Box-Behnken experimental design for optimizing process parameters in carbonate-promoted direct thiophene carboxylation reaction with carbon dioxide

Qingjun Zhang1, Youguang Ma1,2, Xigang Yuan1,2, Aiwu Zeng1,2   

  1. 1 State Key Laboratory of Chemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China;
    2 Chemical Engineering Research Center, Collaborative Innovative Center of Chemical Science and Engineering (Tianjin), Tianjin 300350, China
  • Received:2022-03-23 Revised:2022-09-13 Online:2022-10-28 Published:2023-01-04
  • Contact: Aiwu Zeng,E-mail:awzeng@tju.edu.cn

摘要: A feasible synthesis route is developed for achieving the direct carboxylation of thiophene and CO2 in a relatively mild solvent-free carboxylate-assisted carbonate (semi) molten state. The effects of reaction factors on the carboxylate yield are investigated in the preliminary screening experiments, and the phase behavior analysis of the reaction medium is detected through the thermal characterization analysis of in-situ high temperature X-ray diffraction measurement (in-situ XRD). The application of response surface methodology (RSM) based on the Box-Behnken design (BBD) is conducted to investigate the effect of the reaction parameters, such as reaction temperature, carbonate proportion, CO2 pressure and thiophene amount, on the product yield. The regressed second-order polynomial model equation well correlates all the independent variables. The analysis of variance (ANOVA) results reveal that the quadratic effect of reaction temperature is the most effective parameter in this carboxylation reaction owing to it’s the highest contribution to the sum of square (30.18%). The optimum reaction conditions for maximum product yield are the reaction temperature of 287 ℃, carbonate proportion of 32.20%, CO2 pressure of 1.0MPa and thiophene amount of 9.35 mmol. Operating under these selected experimental conditions, a high product yield (50.98%) can be achieved.

关键词: Carboxylation, Solvent-free medium, Molten salt, Optimization, Response surface methodology

Abstract: A feasible synthesis route is developed for achieving the direct carboxylation of thiophene and CO2 in a relatively mild solvent-free carboxylate-assisted carbonate (semi) molten state. The effects of reaction factors on the carboxylate yield are investigated in the preliminary screening experiments, and the phase behavior analysis of the reaction medium is detected through the thermal characterization analysis of in-situ high temperature X-ray diffraction measurement (in-situ XRD). The application of response surface methodology (RSM) based on the Box-Behnken design (BBD) is conducted to investigate the effect of the reaction parameters, such as reaction temperature, carbonate proportion, CO2 pressure and thiophene amount, on the product yield. The regressed second-order polynomial model equation well correlates all the independent variables. The analysis of variance (ANOVA) results reveal that the quadratic effect of reaction temperature is the most effective parameter in this carboxylation reaction owing to it’s the highest contribution to the sum of square (30.18%). The optimum reaction conditions for maximum product yield are the reaction temperature of 287 ℃, carbonate proportion of 32.20%, CO2 pressure of 1.0MPa and thiophene amount of 9.35 mmol. Operating under these selected experimental conditions, a high product yield (50.98%) can be achieved.

Key words: Carboxylation, Solvent-free medium, Molten salt, Optimization, Response surface methodology