The catalytic performances of solid acids (Al2O3 derived from bayerite (PBT), gamma-Al2O3 (ALO8), ZSM-5, H-mordenite, and TiO2) in hydrolysis of dimethyl ether (DME) to methanol have been investigated. The stronger and the larger acid sites give rise to higher conversion in hydrolysis; however, fast degradation due to coking and low quality of product are observed. The acid strength of the solid acids is as follows: H-mordenite > ZSM-5 > PBT, ALO8 > TiO2. The apparent activation energies of DME hydrolysis over H-mordenite, ZSM-5, PBT, ALO8, and TiO2 were determined as 73, 76, 101, 146, and 186 U mol(-1), respectively. Next, steam reforming of dimethyl ether over composites of the solid acid and copper iron spinel was evaluated for hydrogen production. The composites of alumina and Cu spine] are active and durable to produce H-2-rich reformate with CO2 as the major products along with trace amounts of CO. The Cu content of 13.3-17.7 wt% in the composites was optimum in terms of reforming performance. Alumina-spinel composites are superior to zeolite-spinel ones with regard to stability. Increasing the steam-to-carbon ratio obviously suppresses the catalyst degradation. (c) 2007 Elsevier B.V. All rights reserved.