Hollow fibre based reactors for an enhanced H₂ production by methanol steam reforming

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• 作者：F.R. Garc铆a-Garc铆a ; S.C. Tsang ; K. Li
• 关键词：Asymmetric Al2O3 hollow fibre ; Methanol steam reforming ; Micro-reactor ; Pd/Ag membrane
• 刊名：Journal of Membrane Science
• 出版年：1 April, 2014
• 年：2014
• 卷：455
• 期：Complete
• 页码：92-102
• 全文大小：4312 K

文摘

In this study, asymmetric Al₂O₃ hollow fibres have been used as a support for either a Cu/Zn/GaO_X based catalyst or a Pd/Ag membrane in the development of a catalytic hollow fibre micro-reactor (CHFMR) and hollow fibre membrane reactor (HFMR), respectively. The Cu/Zn/GaO_X based catalyst was successfully deposited inside the finger-like region of the Al₂O₃ hollow fibres by the co-precipitation technique. The impregnated fibres were characterised by X-ray diffraction (XRD), high resolution optical microscopy, scanning electron microscopy (SEM) and energy-disperse X-ray spectroscopy (EDS). The Pd/Ag membrane was deposited on the outer surface of the Al₂O₃ hollow fibres by the electroless plating technique and was characterized by SEM, and Ar and H₂ permeability. The performance of both the CHFMR and HFMR was compared with that of a conventional fixed-bed reactor (FBR) during the methanol steam reforming (MSR) reaction. The CHFMR offers important advantages over conventional FBRs such as high catalytic activity along with a maximum selectivity. It has been observed that at 300 掳C the CH₃OH conversion in the CHFMR was 6 times larger and the CO produced 4 times smaller than that obtained in a conventional FBR. Likewise, the results obtained using the HFMR during the MSR showed that at 250 掳C the CH₃OH conversion was 75%, which is 34% higher than that obtained in the conventional FBR. Moreover, at 250 掳C and using a sweep gas of 100 ml/min in the HFMR, the H₂ recovery index of the Pd/Ag membranes was 50%, which showed the feasibility of a large production of high purity H₂ (5.5 ml/mg h). The Pd/Ag membrane was stable under the reaction conditions, showing high H₂ permeance (1.2脳10^鈭? mol m^鈭? s^鈭? Pa^鈭?/2 at 300 掳C) and permeability (7.6脳10^鈭? mol m^鈭? s^鈭? Pa^鈭?/2 at 300 掳C) and infinite selectivity to H₂.