U. Galla

Methanol reforming in supercritical water for hydrogen production

ABSTRACT The production of hydrogen by reforming of methanol in supercritical water was studied in continuous flow apparatus made of nickel base alloys. Experiments were performed at pressures from 25 to 45 MPa, temperatures in the range of 400 to above 600°C and residence times from few seconds up to few minutes. The feed concentration varied from 5 to 64 wt.% methanol. The main component of the product gas is H2, carbon is converted to CO2, CO, and CH4. Methanol conversion is up to 99.9% without addition of a catalyst. Oxidation of the reactor inner surface before gasification turned out to enhance the reaction rate and to lower the carbon monoxide concentration. Obviously, the heavy metals of the inner surface of the reactors catalyze the reaction. Pilot-plant tests (with a flow rate of 100 kg/h) confirm the laboratory experiments and give data for the energy balance of the process.