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Abstract: In this study, CuO/CeO2 catalysts with a Cu content ranging from 5% to 40% were synthesized by sol–gel Pechini method and were tested in a fixed-bed reactor for water gas shift (WGS) reaction. The catalysts were characterized by XRD, N2 adsorption isotherms at 77K (S BET) and H2-TPR. Based on the catalytic activity results, 10% CuO/CeO2, identified to be the most active catalyst, was deposited inside finger-like regions of an Al2O3 hollow fibre support for the further development of both catalytic hollow fibre micro-reactor (CHFMR) and catalytic hollow fibre membrane micro-reactor (CHFMMR) where Pd or Pd/Ag membrane was coated on the outer layer of the Al2O3 hollow fibre using a single or multilayer electroless plating (ELP) technique. The prepared catalytic membranes were characterized by SEM, EDX, and pure H2 and Ar permeation. Also, a comparative study of the CO conversion obtained in the WGS reaction as a function of the reaction temperature (from 200°C to 500°C) in a fixed-bed reactor, a CHFMR, a Pd-CHFMMR and a Pd/Ag-CHFMMR, was performed showing that the conversion was highest in the Pd/Ag-CHFMMR. [Copyright &y& Elsevier]

Abstract: This article describes development of a catalytic hollow fibre membrane micro-reactor (CHFMMR) for high purity H2 production. Asymmetric Al2O3 hollow fibres produced by a phase-inversion and sintering technique were employed as a single substrate for both coating of the Pd membrane and impregnation of the 30%CuO/CeO2 catalyst. The Pd membrane was first deposited onto the outer layer of Al2O3 hollow fibre using the electroless plating (ELP) technique, followed by impregnation of the 30%CuO/CeO2 catalyst into the inner finger-like structure of the substrate using the sol–gel Pechini method. Performance of the proposed reactor was carried out using water gas shift (WGS) reaction as a sample reaction. A comparative study of conversion obtained in the WGS reaction as a function of the reaction temperature (from 200°C to 500°C) in a fixed-bed reactor, a catalytic hollow fibre micro-reactor (CHFMR) and the CHFMMR using different flow rates of a sweep gas (from 45 to 70ml/min) was performed, concluding that the conversion is the highest in the CHFMMR. It is important to highlight that, at 500°C and a sweep gas flow rate of 75ml/min, a conversion of 17% higher than the corresponding thermodynamic equilibrium conversion was achieved in the CHFMMR. In the operation of the CHFMMR, high purity H2 has been obtained in the shell side, which was 78% of the total H2 produced in the WGS reaction. [ABSTRACT FROM AUTHOR]

Abstract: A novel catalytic hollow fibre membrane microreactor (CHFMMR), consisting of a thin Pd layer and a 30%CuO/CeO2 catalyst supported on an asymmetric Al2O3 hollow fibre has been developed. In the preparation of the CHFMMR, the Pd layer was deposited on outer surface of the hollow fibre substrate by electroless plating first, followed by impregnation of 30%CuO/CeO2 catalyst in the finger pores located in the inner surface of the hollow fibre lumen by sol–gel coating. The catalytic activity of the CHFMMR was tested using water–gas shift (WGS) reaction and compared to that of a catalytic hollow fibre microreactor (CHFMR) and a conventional fixed-bed reactor. The catalytic activity tests were performed at 1atm and from 200°C to 500°C using different flow rates of sweep gas (from 50 to 75ml/min). The ratio between CO and H2O in the feed was 1 to 0.5 with a space velocity of 80lg−1 h−1. The conversion obtained in the CHFMMR is 35% higher than that in the conventional fixed-bed reactor. Furthermore, a conversion which was 17% higher than the corresponding thermodynamic equilibrium conversion was achieved in the CHFMMR, at 500°C with a sweep gas flow rate of 75ml/min. [Copyright &y& Elsevier]