(141b) A Hybrid Adsorbent-Membrane Reactor (Hamr) System for Hydrogen Production

We present a detailed investigation of the design characteristics and performance of a novel reactor system, termed the hybrid adsorbent-membrane reactor (HAMR). The HAMR concept, originally proposed by our group (Park 2001; Park and Tsotsis, 2004) for esterification reactions, couples the reaction and membrane separation steps with adsorption on the membrane feed or permeate side. The first HAMR system investigated by us involved a hybrid pervaporation membrane reactor, and integrated the reaction and pervaporation steps through a membrane with water adsorption (Park 2001; Park and Tsotsis, 2004). Coupling reaction, pervaporation, and adsorption significantly improved the performance. Most recently our focus has been on new HAMR systems for hydrogen production, of potential interest to pure hydrogen production for proton exchange membrane (PEM) fuel cells for various mobile and stationary applications.

Recently a mathematical model for a HAMR system for hydrogen production through the steam reforming of methane (SRM) reaction has been developed and analyzed for a range of temperature and pressure conditions (Fayyaz et al., 2005). The HAMR system was shown to exhibit enhanced methane conversion, hydrogen yield, and product purity and good promise for reducing the hostile operating conditions of conventional methane-steam reformers, and for meeting the product purity requirements for PEM operation. In this paper we will present experimental investigations of HAMR systems using CO2 hydrotalcite-type adsorbents and nanoporous H2 selective membranes. Dense and nanoporous membranes are utilized and we study both the water gas shift (WGS) and steam reforming reactions. The reactor characteristics have been investigated for a range of temperature and pressure conditions relevant to the aforementioned applications, and are compared with the predictions of the mathematical model.

References:

1.Fayyaz B. etc, Design aspects of hybrid adsorbent-membrane reactors for hydrogen production, Ind. Eng. Chem. Res., 44 (25), 9398 -9408, 2005

2.Park, B., Models and experiments with pervaporation membrane reactors integrated with water removal adsorbent System, Ph.D. Thesis, University of Southern California, Los Angeles, California, 2001.

3.Park, B.; Tsotsis, T. T. Models and Experiments with Pervaporation Membrane Reactors Integrated with an Adsorbent System. Chem. Eng. Proc. 2004, 43, 1171