Abstract: An engine exhaust system is disclosed which in operation is capable of substantially reducing the quantities of hydrocarbons emitted to the atmosphere during engine start-up. The system utilizes molecular sieve means, such as a high-silica zeolite, which function to adsorb hydrocarbons emitted during engine start-up, before the catalytic converter has attained its effective operating temperature. The system is designed so that, once the catalytic converter has attained an effective operating temperature, the hydrocarbons can be desorbed from the molecular sieve means and conveyed to the converter for conversion to non-toxic by-products.

Abstract: An exhaust system for a v-configured transverse-mounted internal combustion engine includes a first passage for the first, front manifold exhaust gas stream having a adsorber structure disposed therein and a second passage for the second exhaust gas stream having an catalyst structure disposed therein. The catalyst and the adsorber comprise a single honeycomb adsorber-catalyst structure having a plurality of partition walls extending along an axial direction of the honeycomb structure. The partition walls form at least two portions including a catalyst portion having a catalyst layer provided thereon and an adsorber portion having a adsorber layer supported thereon. Specifically, the portions are separate from each other in a cross-section extending perpendicular to the aforementioned axial direction. The system further includes burn-off catalyst disposed downstream adsorber-catalyst structure.

Abstract: An improved system for the control of combustion engine exhaust from a motor vehicle includes an adsorber for the adsorption of hydrocarbons concentrated in the exhaust stream at engine startup, the adsorber being of honeycomb shape which includes a peripheral channeled portion and a central channeled portion, the latter including an exhaust gas by-pass port parallel with the channels, with the through-channels in the central portion of the honeycomb having a relatively high resistance to exhaust gas flow compared to the channels traversing the peripheral portion. Systems with reduced secondary air requirements and providing more efficient burn-off of the adsorbed hydrocarbons are also disclosed.

Abstract: The invention is directed at an engine exhaust system comprising: (1) a honeycomb structure having an inlet and outlet end disposed in a housing located in an exhaust gas stream downstream from an engine, and having a first substantially unobstructed flow region, and a second more obstructed flow region adjacent the first region, both providing a flow path for the exhaust gases in the exhaust gas stream; and, (2) a fluidics apparatus disposed in the exhaust stream comprising a bi-convex diverter body with the respective surfaces located upstream and downstream of each other, located upstream and proximate to the first region, a diversion fluid source and a conduit possessing a rounded outlet for directing the diversion fluid toward the diverter body.

Abstract: A process of using a catalyst system for the oxidation of hydrocarbons, carbon monoxide, and the reduction of nitrogen oxides is provided. The unique synergy of the catalyst system, a combination of molecular sieves and noble metals, provides a system that partially or entirely replaces the need for rhodium as a catalyst in three way catalyst systems.

Abstract: A catalyst system for the oxidation of hydrocarbons, carbon monoxide, and the reduction of nitrogen oxides is provided. The unique synergy of the catalyst system, a combination of molecular sieves and noble metals, provides a system that partially or entirely replaces the need for rhodium as a catalyst in three way catalyst systems.

Abstract: An engine exhaust system disclosed which is designed to reduce hydrocarbon emissions caused by the evaporation of fuel from the fuel tank and by the inefficiency of combustion and catalytic conversion during cold engine start-up. This system utilizes molecular sieves, such as high-silica zeolites, which adsorb hydrocarbons evaporating from the fuel tank or emitted during engine start-up, before the catalytic converter has attained an effective operating temperature. This system is designed so that hydrocarbons that would otherwise be emitted to the atmosphere from the fuel tank or by passing through the converter unconverted are held within the system either for combustion in the engine or passage through the converter once it is operating efficiently.

Abstract: An engine exhaust system and method of controlling hydrocarbon emissions are provided. The system and method are based on the use of two catalytic converter chambers, a first chamber containing a catalytic material and a second chamber containing catalyst as well as molecular sieves capable of adsorbing hydrocarbons during engine start-up and of having hydrocarbons desorbed therefrom when the catalysts reach an effective converting temperature. According to the invention, engine exhaust is selectively conveyed to each of the two converters in a manner such that initially produced hydrocarbon is withheld in the system by the molecular sieves in order to be recycled through the converters and brought into contact with the catalyst after an effective converting temperature has been attained.

Abstract: Magnesia partially-stabilized zirconia ceramic materials can be prepared from "unpurified" zirconia which contains at least about 0.05 weight percent silica. Despite the relatively high silica content, a thermal shock resistant material can be produced by a firing schedule which includes heating to a top temperature at a specified rate and cooling back to room temperature at specified rates and which incorporates a thermal aging step at 1000-1200.degree. C. Differences in microstructure and monoclinic zirconia content, with consequent differences in physical properties of the ceramic material, can be attained by variations in the firing and thermal-aging schedules.

Abstract: A solid fuel heating appliance in the form of a wood burning stove employs a combustor for oxidizing oxidizable species in the exhaust. A flame break is provided between the combustor and the combustion chamber of the stove to avoid impingement of flames on the combustor.

Abstract: Method and apparatus is set forth for extruding honeycomb structures having cohesive cellular walls from an extrusion die. A baffle member is provided within the flow passageways of the die so as to provide impedance to longitudinal batch flow through certain of the discharge slots such that the impedance to flow in all of the slots is substantially equal, thus improving product quality and knitting or cohesiveness of the batch material prior to discharge from the die.

Abstract: Method and apparatus is set forth for extruding honeycomb structures having cohesive cellular walls from an extrusion die. Deflector means are provided within flow passageways of the die, wherein the deflector means has a secondary feed system such that the batch flow from the main feed system is broken up into a multi-channel stream system which improves the flow of the batch material into the discharge slots, thus improving product quality and knitting or cohesiveness of the material prior to discharge from the die.