Performance of reactive distillation columns with multiple reactive sections for the disproportionation of trichlorosilane to silane
With reference to the disproportionation of trichlorosilane to silane, a three-stage consecutive reversible reaction with a rather unfavorable reaction kinetics, in-depth comparison in steady-state performance is performed between the column with a single reactive section and those with multiple reactive sections, adopting the equal number of trays and the equal amount of catalyst. The reactive distillation column with multiple reactive sections appears to be considerably superior in the aspect of economic advantages to the reactive distillation columns with single reactive section and these strengths originate essentially from the additional degrees of freedom resulted from the arrangement of multiple reactive sections in process synthesis and design. Arrangement of side-condensers is also examined towards the columns with multiple reactive sections and the outcomes reveal the thermodynamic rational to adopt multiple reactive sections in process development. Although these findings are derived from the specific case study chosen, it should be regarded as the significant potential for analyzing the reactive distillation columns with intricate multiple reversible reactions and separating intricate multiple components.
Reactive distillation with side draw
We demonstrate the applicability of a new reactive distillation configuration, i.e. reactive distillation with side draw, for certain industrially important reactions. For the reacting systems which involve products with intermediate volatility, a side draw facilitates its in situ removal and enhances either conversion or selectivity. It further reduces the downstream processing in some cases. The concept is proved for three representative systems, viz. esterification of lactic acid, aldol condensation of acetone and for esterification of fatty acid by methanol. Experimental proof is also provided in some cases.
Two-Step Reactive Distillation Process for Cyclohexanol Production from Cyclohexene
The present work deals with a novel and attractive alternative process route for the production of cyclohexanol by indirect hydration of cyclohexene using reactive distillation. The proposed two-step process comprises the esterification of cyclohexene with formic acid followed by the hydrolysis of the formed ester. The principle feasibility of this new process has recently been proved by means of residue curve analysis [Steyer et al. Ind. Eng. Chem. Res. 2008, 47, 9581−9587]. In the present contribution, detailed equilibrium stage simulations are performed to identify the optimum design and operating conditions for the coupled reactive distillation column scheme. The simulations reveal that it is possible to achieve almost complete conversion of cyclohexene to cyclohexanol with a comparatively low amount of catalyst. To the best of our knowledge, this is the first time that such an outstanding performance of a process for the production of cyclohexanol is reported.