Ceramic hollow fibres catalytic enhanced reactors for glycerol steam reforming

Abstract

In this study, NiO/MgO/CeO2 catalysts with Ni content from 5% to 30% were synthetized by sol–gel method and tested in a fixed-bed reactor (FBR) in the glycerol steam reforming (GSR) reaction. The catalysts were characterized by N2 adsorption isotherms at −196°C (SBET), X-ray diffraction (XRD), H2 temperature programmed reduction (H2-TPR), transmission electron microscopy (TEM) and energy dispersive X-ray (EDX). The 20% NiO/MgO/CeO2 catalyst, which showed the highest catalytic activity in GSR reaction, was selected to be deposited in the finger-like region of the asymmetric Al2O3 hollow fibre and the sponge-like region of the symmetric Al2O3 hollow fibre in the development of the asymmetric hollow fibre reactor (AHFR) and symmetric hollow fibre reactor (SHFR), respectively. The impregnated ceramic substrates were characterized by scanning electron microscopy (SEM), EDX and TEM. The performances of the AHFR and SHFR were compared with that in a conventional FBR during the GSR reaction. Both AHFR and SHFR were operating at “dead-end” configuration at a temperature range from 250°C to 550°C, atmospheric pressure and in a reactant mixture of steam and glycerol (16:1 molar ratio). At 550°C the glycerol conversion in the AHFR and SHFR was 70% and 46%, respectively, which are 5 and 2 times higher than that obtained in the FBR. The different performances of the AHFR and SHFR could be explained due to the unlike catalyst particle size deposited in the asymmetric and symmetric substrates, 8nm and 3nm, respectively.