Wouldn't it be wonderful if you could buy an electric car and yet refuel it in a matter of minutes at the corner gas station? Researchers with Arthur D. Little Int'l. claim to have developed technology that will make such a scenario possible.
They've created a fuel reformer which can extract the hydrogen from gasoline and make it available for a PEM fuel cell. It consists of a cylindrical fuel processor 17 X 22 inches. This "can," as its inventor, Jeffrey Bentley, vice president of technology and product development for ADL, calls the fuel processor, is made of stainless-steel 310 and contains finned tubular heat exchangers, fuel injectors from automotive controls, air valves, and automatic controls.
"One of the key benefits," Bentley says, "is that it uses fairly common materials, which contributes to its low cost."
The processor's simple exterior is deceiving. Inside, the hydrocarbon fuel--gasoline, for instance--is mixed and superheated to 1,800F using waste energy from the fuel cell. The heat-recapturing process results in an 84% conversion efficiency compared to just 15% for an internal combustion engine. Overall vehicle efficiency should be improved roughly 50%, with 90% better emissions compared to internal combustion engine-powered automobiles.
The mixture then passes to a partial oxidation (POX) reaction zone, where it is split into hydrocarbon and hydrogen and carbon. Next, a nickel catalyst takes care of methane formed in the reaction process and creates more usable hydrogen. Heat exchangers and shift reactors then convert the mixture to carbon dioxide and hydrogen.
The processor's ability to work with gasoline made it a big hit when introduced, but the system will work just as well--perhaps better--with other fuels, such as ethanol or methanol.
Whatever the fuel, the hydrogen rich gas produced by the processor must pass through a carbon monoxide cleanup module that preferentially oxidizes (PROX) the mixture to reduce CO concentration from 2,000 to 10 ppm. This prevents slow poisoning of the fuel cell. Sulfur byproducts are collected in a trap which is expected to last the lifetime of the vehicle.
Chrysler has publicly committed to developing a prototype fuel cell car within two years that incorporates the processor.