Multiphase catalytic reactions in a trickle bed reactor

[摘要] Successful transfer of multiphase catalytic reactions from laboratory to commercial scale depends on proper understanding of all the parameters involved. This thesis aims to further understand these aspects with regards to trickle beds. A detailed discussion of reaction kinetics, hydrodynamics and mass transfer is presented for three industrially important reactions. The catalytic hydrogenation of dimethyl itaconate was studied in lab-scale shake flask and transferred to continuous flow with recirculation in a trickle bed reactor (TBR). The TBR was operated in the trickle flow regime using the catalyst complex [Rh((R,R)-Me-DuPhos)(COD)]BF4 supported on ion-exchange resins and trilobe alumina. Under optimized conditions in the TBR, 99% conversion and enantioselectivity of up to 99.9% were achieved. After elimination of all diffusional resistances, the experimental data could be fitted well by means of a kinetic model based on the Osborn-Wilkinson reaction mechanism. The selective hydrogenation of 1-heptyne over a 2 wt. % Pd/Al2O3 catalyst was studied in a TBR operating in both batch recycle and continuous modes. Solvent selection and liquid flow rate were found to have a noticeable effect on reaction rate and selectivity. The concentration profiles were fitted according to a Langmuir-Hinshelwood kinetic expression. Under optimized conditions in the TBR, 100% selectivity to 1-heptene was maintained up to 84% conversion of 1-heptyne. The selective hydrogenation of soyabean oil over a 2 wt. % Pd/Al2O3 catalyst was assessed in a TBR operating in a batch recycle mode. Reaction temperature, hydrodynamics and oil volume were found to have a noticeable influence on reaction rate and selectivity. It was demonstrated that under proper reaction conditions, the composition of soyabean oil can be upgraded to produce base oils for lubricants.

[发布机构] University:University of Birmingham;Department:School of Chemical Engineering

[关键词] T Technology;TP Chemical technology