John J. Steger

Fuel modification method and apparatus for reduction of pollutants emitted from internal combustion engines

A method for controlling exhaust gas emissions from an engine (16) includes extracting a light distillate fuel (Fd) from conventional gasoline or other liquid hydrocarbon fuel and supplying the engine with the light distillate fuel during an initial operation period of the engine. This reduces the oxidizable pollutants in the engine exhaust during a cold-start period before a catalytic converter (22) used to abate pollutants in the engine exhaust gases has not yet attained its operating temperature. After the catalytic converter (22) has been sufficiently heated, the fuel supply to the engine (16) is switched to gasoline or other liquid hydrocarbon fuel. Both the distillate fuel (Fd) and the liquid hydrocarbon fuel may be passed through a heated cracking catalyst bed (30) to crack the fuel fed to the engine.

Design of a novel Pd three-way catalyst: Integration of catalytic functions in three dimensions

Abstract Performance of Pd catalysts for three-way conversion of HC/CO/NO is characterized using simulated auto exhaust gas over a wide temperature range from 423 to 823 K. For Pd catalysts, HC/CO/NO conversions increase sharply around 570 K. Introduction of ceria in Pd catalysts reduces NO conversion at low temperature around 600 K, while increases NO conversion at high temperature around 770 K. The lower NO conversion is attributed to a lower Pd function resulted by intimate PdCe interaction. The enhanced NO conversion at high temperature is related to a higher oxygen storage capacity provided by ceria. In addition, base metal oxide additives are found to enhance Pd catalysts performance over the wide temperature range tested. An integrated Pd only catalyst washcoat architecture, consisting of a Pd top layer and a PdCe bottom layer, is designed to maximize HC/CO/NO performance over a wide operating temperature range. Engine and vehicle evaluation results show that this Pd catalyst, integrating Pd sites and oxygen storage components in three dimensions, is superior in three-way performance to current Pt/Rh catalysts, and can be applied to meet stringent Californian low emission vehicle standards.