Improving mass-transfer in controlled pore glasses as supports for the platinum-catalyzed aromatics hydrogenation

M Goepel,C Küster,C Chmelik,D Enke,J Kärger,R Gläser,R Valiullin,P Zeigermann,H Kabir,E Saraçi

doi:10.1039/c4cy01665c

Abstract

Mass-transfer improvement in the Pt-catalyzed aromatics hydrogenation by increasing the pore width of controlled pore glasses as supports.

Highlights

Hydrogenation reactions play an important role in many industrial heterogeneously catalyzed reactions such as the removal of hetero atoms from crude oil fractions,[1] the transformation of unsaturated to saturated hydrocarbons[2,3] the defunctionalization of biomass,[4] the reduction of carbonyl[5] and nitro groups in organic subtrates[6] as well as the production of pharmaceuticals, fine and bulk chemicals.[7]
3.1 Pt catalysts supported on controlled pore glasses (CPGs) beads
To ensure comparability of the textural data obtained, Hg-intrusion measurements were conducted on the catalysts Pt/CPG(4) and Pt/CPG(10) (ESI,† Fig. S1 and S2)

Summary

Introduction

Hydrogenation reactions play an important role in many industrial heterogeneously catalyzed reactions such as the removal of hetero atoms from crude oil fractions,[1] the transformation of unsaturated to saturated (cyclic) hydrocarbons[2,3] the defunctionalization of biomass,[4] the reduction of carbonyl[5] and nitro groups in organic subtrates[6] as well as the production of pharmaceuticals, fine and bulk chemicals.[7]. Materials with hierarchically structured pore systems (often zeolite-based) generated interest due to their potential of overcoming mass-transfer limitations in heterogeneously catalyzed conversions.[14,15,16] These materials are most attractive due to the combination of the zeolitic micropores, providing a high surface area, and the larger pores (typically mesopores, d = 2–50 nm) providing improved accessibility to the micropores containing the majority of the catalytically active sites. The mesopores mainly act to supply mass transfer routes within the catalyst particles resulting in an increased effectiveness factor. Several reports in this field attribute the higher catalytic activity to improved mass-transport in hierarchically structured pore systems.[17,18,19] It is, noteworthy that experimental data on the mass-transport in these catalytic systems are rarely presented. Knowledge about the required pore width for unhindered mass-transfer in the larger (meso)pores is needed to arrive at a rational design of hierarchically structured catalysts

Objectives

Results

Conclusion