An experimental study of the performance of a novel reactor system-termed the hybrid adsorbent-membrane reactor (HAMR)-is described. In the HAMR the reaction and membrane separation steps are coupled with adsorption. It was shown previously by our group for esterification reactions that this system results in significantly improved performance. The focus in this paper is on the use of the HAMR for hydrogen production. We present experimental investigations of the HAMR for the water-gas-shift (WGS) reaction using layered double hydroxides as adsorbents for CO2 and nanoporous H-2-selective carbon molecular sieve membranes. The reactor characteristics are investigated for a range of temperatures and pressures relevant to the WGS application, and are compared with the predictions of a mathematical model previously developed by our group. (c) 2007 Elsevier Ltd. All rights reserved.