Methanol steam reforming in an Al_2O_3 supported thin Pd-layer membrane reactor over Cu/ZnO/Al_2O_3 catalyst

摘要

In this experimental study, a membrane reactor housing a composite membrane constituted by a thin Pd-layer supported onto Al_2O_3 is utilized to perform methanol steam reforming reaction to produce high-grade hydrogen for PEM fuel cell applications. The influence of various parameters such as temperature, from 280 to 330 ℃, and pressure, from 1.5 to 2.5 bar, is analyzed. A commercial Cu/Zn-based catalyst is packed in the annulus of the membrane reactor and the experimental tests are performed at space velocity equal to 18,500 h~(-1) and H_2O;CH_3OH feed molar ratio equal to 2.5:1. Results in terms of methanol conversion, hydrogen recovery, hydrogen yield and products selectivities are given. As a best result of this work, 85% of methanol conversion and a highly pure hydrogen stream permeated through the membrane with a CO content lower than 10 ppm were reached at 330 ℃ and 2.5 bar. Furthermore, a comparison between the experimental results obtained in this work and literature data is proposed and discussed.