Catalytic membrane reactor for the production of biofuels

Abstract

The H2-distributed feeding concept using Pd/Ag based membranes and Ru-based catalyst in Packed Bed Membrane Reactor (H2-PBMR) for the synthesis of biofuels via the so-called Fischer-Tropsch Synthesis has been demonstrated. The most successful approach resulted when H2-poor syngas (H2/CO=1) typically obtained from the gasification of biomass, was feed directly through the reaction chamber, i.e., to the catalyst bed, whereas the H2 needed to reach the proper stoichiometry for the FTS (H2/CO=2) was admitted, and properly distributed, into the catalyst bed through the Pd/Ag-based membrane by flowing H2/He mixtures at the outer side of the membrane. Under the optimum reaction conditions, the CO conversion recorded with the H2-distributed feeding concept is lower than that obtained in a conventional Packed Bed Reactor with H2/CO =2 (37.9 vs 50.7 %) but significantly higher than that obtained in a conventional reactor with H2/CO =1 (14.1 %). Remarkably, productivity towards high-molecular hydrocarbons increases by almost a 70 % and methane production decreases by one order of magnitude when H2-distributed feeding concept in Packed Bed Membrane Reactor is used.