Catalysts make hydrogen under the hood.

Government researchers have discovered a new class of catalysts that convert fossil fuels into clean-burning hydrogen gas at temperatures much lower than previously thought possible.

Because combustion of hydrogen produces only heat and water, automakers hope to tap it as fuel for a new generation of pollution-free vehicles. Without a national system of hydrogen filling stations, however, engineers are designing cars with onboard reactors that can generate hydrogen from gasoline (SN: 11/1/97, p. 279). Currently available reactors operate at temperatures of 1,100 [degrees] C or higher, says Shabbir Ahmed of the Department of Energy's Argonne (Ill.) National Laboratory. These hot temperatures mean high engine wear and energy usage.

The new catalysts, whose composition the Argonne researchers have not revealed, operate below 800 [degrees] C and work on a variety of fuels. Gasoline and diesel exposed to the materials yield a mixture of gases that is 60 percent hydrogen, while natural gas yields 42 percent. The catalysts also seem not to plug up reactors with solid carbon, a problem with other catalysts.

About 2 liters of a catalyst in pellet form can generate a hydrogen flow that will yield about 3 kilowatts of power. A light vehicle needs 40 to 50 kW to run. If others confirm the results, says Argonne's Michael Krumpelt, "industry will have to come to its own conclusions" about the usefulness of the catalysts. The scientists are currently seeking a patent for the materials.