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The concept of using two-stage combustion in a spark ignition engine has been tested in a single cylinder CFR engine. The engine was operated over an equivalence ratio range of 1.5 to 2.2 to evaluate the first stage of combustion. The product gas was analyzed for H2, CO, CO2, and hydrocarbons. An atmospheric burner was operated with gasoline over the same equivalence ratio range of 1.5-2.2, and the resulting product gases were then burned in the CFR engine to test the second stage of combustion. Emissions of NOx, HC and CO of 0.1, 0.1, and 5 gm/IHP-hr were measured respectively. The engine indicated efficiency for the two-stage mode was essentially the same as for the single-stage mode.

A compact onboard hydrogen generator has been developed for use with a hydrogen-enriched gasoline internal combustion engine. The unit uses gasoline and air in a partial oxidation reactor to produce a gaseous product containing hydrogen, carbon monoxide, minor amounts of methane, carbon dioxide and water, and nitrogen. A study of the theoretical equilibrium product composition has indicated an optimum operating point at an air/fuel ratio of 5.15, where a hydrogen/fuel mass ratio of 0.136 can be obtained under soot-free conditions. This is based on a gasoline with an atomic hydrogen to carbon ratio of 1.92. Both thermal and catalytic reactors have been tested. The thermal unit requires a reaction temperature of 2400°F to obtain 80% of the theoretical hydrogen yield. Soot formation tends to be a problem. The catalytic reactor yields close to theoretical yields at an operating temperature of 1800°F without any soot formation. A commercial nickel catalyst is used.