Catalytic hydrogen production from 2-propanol in supercritical water: Comparison of some metal catalysts

Abstract

The gasification of organics in supercritical water is a promising method for the direct production of hydrogen at high pressures, and in order to improve the hydrogen yield or selectivity, activities of various catalysts are evaluated. In this study, hydrogen production from 2-propanol over Ni/Al2O3 and Fe-Cr catalysts was investigated in supercritical water. The experiments were carried out in the temperature range of 400-600 degrees C and in the reaction time range of 10-30 s, under a pressure of 25 MPa. The hydrogen yields and selectivities of Ni/Al2O3 and Fe-Cr used in this study, and those of Pt/Al2O3 and Ru/Al2O3 used in our previous work were compared. The hydrogen contents of the gaseous products obtained by using Ni/Al2O3 and Fe-Cr were measured as 62 mol% and 70 mol%, respectively, at low temperatures and reaction times. However, the hydrogen yields remained in low levels when compared with that of Pt/Al2O3 used in previous study. Pt/Al2O3 was established to be the most effective and selective catalyst for hydrogen production. During the catalytic gasification of a 0.5 M solution of 2-propanol, hydrogen content up to 96 mol% and hydrogen yield of 1.05 mol/mol 2-propanol were obtained. (C) 2014 Elsevier B.V. All rights reserved.