Enhancement of Catalyst Performance Using Pressure Pulses on Macroporous Structured Catalysts

This paper explores the enhancement of catalyst performance by inducing convection inside a macroporous catalyst carrier. The catalyst carrier used was an acicular mullite monolith with highly permeable microstructured walls. The monolith walls were coated with colloidal silica and impregnated with Pd. After performing the proper preparation steps, the high permeability of the walls was preserved and the catalyst was uniformly distributed with a low effective diffusion length. The catalyst performance of the selective hydrogenation of 3-methyl-1-pentyn-3-ol was investigated in a monolithic stirrer reactor, under internal diffusion-limited conditions, using different silica-supported palladium monoliths. At 2.3 bar H2, 20 mol/m3 alkyne, and 25 °C, using equal catalyst loadings, the activity per unit monolith volume was 100% greater and the maximum yield of the alkene was 9% greater for the mullite monolith than for the eggshell-coated monolith with impermeable walls. This confirms that internal diffusional...