화학공학소재연구정보센터
International Journal of Hydrogen Energy, Vol.32, No.18, 5059-5066, 2007
Purification process for chemical storage of hydrogen for fuel cell vehicles applications
An alternative way to provide hydrogen in fuel cell vehicles (FCV) consists of storing hydrogen in liquid hydrocarbons. Supplying hydrogen is then performed, e.g. by dehydrogenation of cycloalkanes and purification through various methods. Two main separation processes were investigated: membranes (zeolite and palladium, both on porous ceramic supports) and adsorption. Separation through zeolite membranes is shown to be inappropriate for FC application since the toluene content in the permeate is still too high (> 2000 ppm). Palladium membranes are more promising for this application. The permeation for the two membranes were found at 4.73 x 10(-4) mol m(-2) s(-1) and 5.06 x 10(-2) mol m(-2) s-1, respectively (at Delta P of 50 kPa. and toluene inlet mole fraction of 12%, temperature 400 degrees C), while the separation factor of the two membranes for the hydrogen over toluene (S-f(H2/Tol)) was found infinite and 40, respectively. When toluene is present at high concentration, the diffusion of hydrogen is remarkably hindered due to a relatively strong adsorption of toluene in the membranes (on the micropores in case of zeolite, and on the Pd film in case of palladium). (c) 2007 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.