Propylene hydrogenation through structured and conventional catalyst beds: Experiment and modeling

• The dynamic mathematical modeling has been solved via orthogonal collocation method.
• The more the liquid flowrate increases the more the discrepancy between model output and experimental data diminishes.
• Stability of structured catalyst bed against the liquid phase velocity variation is more stable than conventional catalyst bed.

Structured packings have been applied since forty years ago, and their advantages over conventional packings have been proved; however, they are not utilized broadly in industrial process. In order to increase the performance of catalytic reactions, it is possible to produce some solid-phase catalysts in the physical form of structured packings. To reduce operational costs, process industries require structured catalysts that have large specific area, provide high mass transfer coefficient and cause low pressure drop. In this study a pilot trickle bed reactor with 155 cm length and 14 cm diameter, is setup that includes an automatic-stroke dosing pump, supply of hydrogen and liquid propane and necessary instrumentation to measure flowrate, pressure and temperature. Performance of the trickle bed pilot reactor has been studied when it is packed with conventional type and structured-shaped catalysts under different liquid phase flowrates. For each type of catalyst and operating conditions sampling along the reactor is performed at specific sampling points once steady-state conditions established. Composition of samples were analyzed and used as experimental data. Dynamic model of the trickle bed pilot reactor is developed in which mass transfer resistance is considered in liquid phase and assumed to be negligible in gas phase. The outputs of dynamic model at different steady-state conditions are compared with experimental data that shows good agreement between these two that indicates model reliability.