Abstract: A system is described for improving engine and vehicle performance by considering the effects of exhaust conditions on catalyst particle growth. Specifically, engine operation is adjusted to reduce operating in such conditions, and a diagnostic routine is described for determining the effects of any operation that can cause such particle growth. Further, routines are described for controlling various vehicle conditions, such as deceleration fuel shut-off, to reduce effects of the particle growth on emission performance.

Abstract: A system is described for improving engine and vehicle performance by considering the effects of exhaust conditions on catalyst particle growth. Specifically, engine operation is adjusted to reduce operating in such conditions, and a diagnostic routine is described for determining the effects of any operation that can cause such particle growth. Further, routines are described for controlling various vehicle conditions, such as deceleration fuel shut-off, to reduce effects of the particle growth on emission performance.

Abstract: A system is described for improving engine and vehicle performance by considering the effects of exhaust conditions on catalyst particle growth. Specifically, engine operation is adjusted to reduce operating in such conditions, and a diagnostic routine is described for determining the effects of any operation that can cause such particle growth. Further, routines are described for controlling various vehicle conditions, such as deceleration fuel shut-off, to reduce effects of the particle growth on emission performance.

Abstract: The invention relates to a method of making a rhodium containing phase of a catalyst system useful to treat the exhaust gases of an internal combustion engine. The method comprises hydrothermally pre-treating the alumina prior to its impregnation with a preferably low loading of rhodium. Preferably the alumina is .alpha.-alumina.

Abstract: This invention is a method for preparing an automotive catalyst system. It comprises the steps of providing a substrate, providing a gamma-alumina support material, depositing a lanthana precursor and calcining the precursor, depositing an oxygen storage material precursor like ceria precursor and calcining this precursor material, and subsequently depositing catalytic material like platinum on the oxygen storage material. The alumina may be initially washcoated on the substrate or at any stage after deposition of the lanthana precursor.

Abstract: The invention relates to an improved emission control system. The system has particular applicability for use in an internal combustion engine (10) utilizing alternative fuels such as natural gas. More particularly, the invention provides an apparatus and method wherein hydrogen is removed by a conditioning catalyst (16) from the exhaust gas stream (21) to produce a conditioned exhaust gas (22). An exhaust gas oxygen (EGO) sensor (18) is in communication with the conditioned exhaust gas (22) and generates a signal in response to the sensed oxygen concentration of the conditioned exhaust gas (22). The A/F mixture entering engine (10) is adjusted by closed loop control means (14) in response to the signal generated by EGO sensor (18). The removal of hydrogen from the exhaust gas stream (21) eliminates lean shifts and allows oxygen sensor (18) and closed loop control means (14) to more accurately control the A/F ratio.

Abstract: An integral manifold-muffler-catalyst device (for an internal combustion engine having a plurality of combustion cylinders generating exhaust gases), comprising: (a) a monolithic catalyst having a plurality of aligned passages for effecting laminar flow of the exhaust gases therethrough while; (b) a high temperature resistant chamber assembly for close-coupling the catalyst to the engine having (i) an expansion chamber for substantially dissipating low frequency standing sound waves of said exhaust gases and for modifying high frequency sound waves of said exhaust gases and (ii) manifolding passages at one side of the expansion chamber for collecting and delivering the exhaust gases from the cylinders to the expansion chamber; and (c) means for effecting converging flow from said expansion chamber to and across substantially the full entrance face of said aligned passages, as well as from the catalyst, for effecting attenuation of high frequency sound waves carried by the exhaust gases.

Abstract: An integral manifold-muffler-catalyst device (for an internal combustion engine having a plurality of combustion cylinders generating exhaust gases), comprising: (a) a monolithic catalyst having a plurality of aligned passages for effecting laminar flow of the exhaust gases therethrough while; (b) a high temperature resistant chamber assembly for close-coupling the catalyst to the engine having (i) an expansion chamber for substantially dissipating low frequency standing sound waves of said exhaust gases and for modifying high frequency sound waves of said exhaust gases and (ii) manifolding passages at one side of the expansion chamber for collecting and delivering the exhaust gases from the cylinders to the expansion chamber; and (c) means for effecting converging flow from said expansion chamber to and across substantially the full entrance face of said aligned passages, as well as from the catalyst, for effecting attenuation of high frequency sound waves carried by the exhaust gases.

Abstract: A practice is disclosed for the start-up of a methanol-fueled engine at low ambient temperatures. Liquid methanol fuel is atomized using ultrasonic energy, mixed with air and introduced over a methanol oxidation-dissociation catalyst. Methanol oxidation is used to heat the catalyst to an elevated temperature at which methanol dissociation provides a noncondensable fuel comprising carbon monoxide and hydrogen for the start-up of the engine at low ambient temperature.

Abstract: A method of treating exhaust gases from an internal combustion engine burning methanol fuel by simultaneously oxidizing the unburned methanol and carbon monoxide at low conversion temperatures by passing the exhaust gases over a catalyst system consisting essentially of silver and palladium dispersed on gamma alumina.