Hydrogen with purity up to 99.9% was produced stably by dehydrogenation of cyclohexane using a membrane reactor with a hydrogen-selective amorphous silica membrane. This membrane reactor was operated successfully under pressure with no carrier gas on the reaction side or any sweep gas on the permeate side, which is a first in the case of the silica membrane. The reactor could supply hydrogen at atmospheric pressure, with only very small amounts of benzene and unreacted cyclohexane, directly to a fuel cell. In addition, this membrane reactor showed excellent performance stability during five startup-operate-shutdown cycles without any special regeneration process. (C) 2008 Elsevier B.V. All rights reserved.