Abstract: A calorimetric sensor for sensing hydrocarbon emissions in an exhaust gas emission monitoring system is provided with at least first and second areas coated with different first and second catalysts so that one catalyst coated area produces oxidation with HC, CO and H.sub.2 and the other catalyst produces oxidation with CO and H.sub.2 but not with HC. Temperature increases attributed to the oxidation reactions are sensed by first and second RTDs while the temperature of an uncatalyzed sensor area is sensed by a reference RTD. Thermal temperature signals for each first and second RTD is balanced against the reference RTD signal to produce accurate first and second temperature signals which are then subtracted to produce a true signal of the HC concentration in the exhaust gas.

Abstract: An on-board catalytic monitoring system uses an intrusive technique to cause the vehicle's engine to cycle between first and second operating conditions. The first and second operating conditions are chosen such that different concentrations of emissions with different chemistries are present at the first and second operating conditions. A calorimetric sensor with a selective catalyst senses exothermic oxidation reactions produced by the emissions in the exhaust gas passing over the sensor. By matching the catalyst activity with the emission concentrations occurring at the operating conditions, the difference between the heat release sensor signals detected between the first and second operating conditions is indicative of the actual concentration of specific emissions in the exhaust gas stream. The difference or delta signal, obtained without reference to a zero point, provides an excellent correlation to the efficiency of the vehicle's catalytic converter for converting the sensed emission, i.e.

Abstract: A calorimetric sensor system requires a vehicle's internal combustion engine to cyclically operate between first and second conditions to repeatedly produce a varying exhaust gas composition which is consistent from cycle to cycle. The rate of change of the calorimetric sensor's signal as the engine cycles from one to the other condition is mathematically factored, after signal filtering at frequencies of the induced perturbation, to provide signals indicative of the emissions concentration in the exhaust gases, the air/fuel ratio of the engine and whether the engine is operating lean or rich. The signals can be used as fuel control engine signals as well as OBD signals. Additionally, the system can control industrial processes through small process perturbations affecting the compositions of process gases.

Abstract: A catalyst composition comprising at least one first support, at least one first precious metal component, at least one second support, and at least one second precious metal component. The total amount of the first precious metal component comprises from 1 to 99 weight percent based on the total of the first and second precious metal components. The average particle size of the second support is greater than the average particle size of the first support. The present invention includes a method to prepare the catalyst composition and a method to use the catalyst composition as a three-way catalyst. The composition results in a coated layer from a slurry where the more supported first precious metal component is in the bottom half and more supported second precious metal component is in the top half.

Abstract: A catalyst composition comprising at least one first support, at least one first precious metal component, at least one second support, and at least one second precious metal component. The total amount of the first precious metal component comprises from 1 to 99 weight percent based on the total of the first and second precious metal components. The average particle size of the second support is greater than the average particle size of the first support. The present invention includes a method to prepare the catalyst composition and a method to use the catalyst composition as a three-way catalyst. The composition results in a coated layer from a slurry where the more supported first precious metal component is in the bottom half and more supported second precious metal component is in the top half.

Abstract: A method and apparatus converts time-resolved sensor signals into transfer functions and/or cumulative transfer function signals which can be attained by computation means such as by using Fast Fourier Transforms. A signal, as a means to assess catalyst performance such as a signal based on sensing oxygen concentration or air to fuel ratio or hydrocarbon concentration in motor vehicle exhaust in accordance with the present invention is in the time domain and has multiple components at different frequencies. The use of Fast Fourier Transforms isolates the various spectral densities which arise from different frequency components of the complex time domain signal. Cross spectral density function and power spectral density function are used to determine the transfer function. The analysis has been found to be substantially independent of operating conditions. The transfer function and cumulative transfer function have been found to be a precise indication of the catalyst performance.

Abstract: A catalyst composition comprising at least one first supports, at least one first precious metal component, at least one second supports, and at least one second precious metal component. The total amount of the first precious metal component comprises from 1 to 99 weight percent based on the total of the first and second precious metal components. The surface area of the at least one first support is greater than the surface area of the at least one second support. Optionally or alternatively, the average particle size of the at least one first supports is greater than the average particle size of the at least one second supports. The present invention includes a method to prepare the catalyst composition and a method to use the catalyst composition as a three-way catalyst.

Abstract: The present invention relates to a zirconium, rare earth containing composition comprising zirconium, cerium, neodymium and praseodymium components and the use of this composition in a catalyst composition useful for the treatment of gases to reduce contaminants contained therein and method process to make the catalyst composition. The catalyst has the capability of substantially simultaneously catalyzing the oxidation of hydrocarbons and carbon monoxide and the reduction of nitrogen oxides.

Abstract: A catalytic material effective for the reduction of NO.sub.x and the oxidation of at least carbon monoxide includes an oxygen storage component that provides superior oxygen storage function. The oxygen storage component includes an intimately combined mixed oxides including cerium, neodymium and zirconium. Typically, the ceria constitutes more than about 30 percent by weight of the ceria plus zirconia in the intimately combined mixed oxide, e.g., from about 32 to 44 weight percent. Preferably, the intimately combined mixed oxide also includes up to about 26 percent neodymia by weight of the ceria, e.g., from 18.6 to 23.5 percent. The intimately combined mixed oxide may be a co-formed material that may be prepared by, e.g., co-precipitating compounds of zirconium and the rare earth metal and calcining the co-precipitate.

Abstract: A NO.sub.x abatement composition comprises a NO.sub.x abatement catalyst and a NO.sub.x sorbent material which are dispersed in proximity to, but segregated from, each other on a common refractory carrier member (10). The NO.sub.x sorbent material comprises a basic oxygenated metal compound and optionally further comprises ceria. The NO.sub.x abatement catalyst contains a catalytic metal component including a platinum metal catalytic component. The catalytic metal component is segregated from the NO.sub.x sorbent material, which may be one or more of metal oxides, metal carbonates, metal hydroxides and mixed metal oxides. At least the catalytic metal component and the NO.sub.x sorbent material must be on, or comprise separate, particles; the particles may either be admixed or may be disposed in separate layers (20a, 20b) on the carrier member (10). A NO.sub.

Abstract: A catalyst composition containing one or more binary oxides of palladium and rare earth metal such as Ce, La, Nd, Pr and/or Sm. The catalyst composition is used for the catalytic combustion of gaseous combustion mixtures of oxygen and carbonaceous fuels such as methane, e.g., a natural gas/air combustion mixture. Specific preferred binary oxides may be, for example, M.sub.2 O.sub.3.PdO (e.g., La.sub.2 O.sub.3.PdO) or 2M.sub.2 O.sub.3.PdO, wherein in each case M is La, Nd or Sm. A process of combusting gaseous carbonaceous fuels includes contacting a catalyst as described above under combustion conditions, e.g., 925.degree. C. to 1650.degree. C. and 1 to 20 atmospheres pressure, to carry out sustained combustion of the combustion mixture, including catalytically supported thermal combustion. Regeneration of over-temperatured M.sub.2 O.sub.3.PdO catalyst is also provided for.

Abstract: The present invention relates to a composition comprising at least one zeolite consisting essentially of the zeolites selected from the group of neutral and basic zeolites and at least one platinum group metal component. This composition has been found to be useful in a method of treating gas streams comprising hydrocarbons comprising the steps of adsorbing the hydrocarbons on the recited zeolites at a low adsorption temperature range, releasing the hydrocarbons from the zeolite at a high release temperature range and oxidizing the hydrocarbons.

Abstract: A catalytic material useful for the abatement of NO.sub.X in a lean environment containing a zeolite material having incorporated therein copper, cobalt and iron as catalytically active species. The catalytically active metals are preferably incorporated into the zeolite by ion exchange and precipitation. The catalytic material may typically contain from about 2.0 to about 8.0 percent copper, from about 1.0 to about 4.0 percent iron and from about 0.25 to about 4.0 percent cobalt by weight of the catalytic material, i.e., by weight of the zeolite material plus the catalytic metals incorporated therein. Optionally, the catalytic material may be admixed with a binder and applied as an adherent coating onto a carrier to be placed in a gas stream containing the nitrogen oxides.

Abstract: A catalyst composition containing one or more binary oxides of palladium and rare earth metal such as Ce, La, Nd, Pr and/or Sm. The catalyst composition is used for the catalytic combustion of gaseous combustion mixtures of oxygen and carbonaceous fuels such as methane, e.g., a natural gas/air combustion mixture. Specific preferred binary oxides may be, for example, M.sub.2 O.sub.3.PdO (e.g., La.sub.2 O.sub.3.PdO) or 2M.sub.2 O.sub.3.PdO, wherein in each case M is La, Nd or Sm. A process of combusting gaseous carbonaceous fuels includes contacting a catalyst as described above under combustion conditions, e.g., 925.degree. C. to 1650.degree. C. and 1 to 20 atmospheres pressure, to carry out sustained combustion of the combustion mixture, including catalytically supported thermal combustion. Regeneration of over-temperatured M.sub.2 O.sub.3.PdO catalyst is also provided for.

Abstract: A method for applying a coating of catalytic material onto a metallic substrate involves thermal spray deposition of refractory oxide particles directly onto the substrate, preferably to attain an undercoat having a surface roughness of Ra 3 or greater. The catalytic material may then be applied to the undercoated substrate in any convenient manner. In a particular embodiment, the metallic substrate is treated by grit blasting prior to the application of an undercoat principally containing alumina. The coated substrate can be used in the assembly of a catalyst member for the treatment of exhaust gases.

Abstract: In an exhaust gas system comprising a hydrocarbon trap (28) and a downstream catalyst zone (30), a heat exchange catalyst member (10) is incorporated into the system to provide heat exchange between the exhaust gas and air that is pumped through the heat exchange catalyst member (10). The heated air is injected into the exhaust gas stream to facilitate the oxidation of hydrocarbons in the downstream catalyst zone. The heat exchange catalyst member (10) defines two separate flow paths therethrough, one of the flow paths containing a catalyst zone for the exhaust gas. In an alternative embodiment, the injected air is heated by a heat exchange trap (28') or by a separate heating element (62).

Abstract: Oxidation catalyst compositions-include a catalytic material containing ceria-and alumina each having a surface area of at least about 10 m.sup.2 /g, for example, ceria and activated alumina in a weight ratio of from about 1.5:1 to 1:1.5. Optionally, platinum may be included in the catalytic material in amounts which are sufficient to promote gas phase oxidation of CO and HC but which are limited to preclude excessive oxidation of SO.sub.2 to SO.sub.3. Alternatively, palladium in any desired amount may be included in the catalytic material. The catalyst compositions have utility as oxidation catalysts for pollution abatement of exhausts contianing unburned fuel or oil. For example, the catalyst compositions may be used in a method to treat diesel engine exhaust by contacting the hot exhaust with the catalyst composition to promote the oxidation of the volatile organic fraction component of particulates in the exhaust.

Abstract: A catalyst composition contains a catalytic material having having an undercoat layer containing a mixture of a fine particulate undercoat refractory metal oxide and a sol such as a silica sol, the undercoat providing good adherence to substrates, such as metal substrates, on which the catalytic material is disposed. An overlayer is coated over the underlayer and contains an overlayer refractory metal oxide, which may be the same as or different from the undercoat refractory metal oxide, and on which is dispersed one or more catalytic metal components, such as palladium and manganese components. The metal substrate may be made of, e.g., aluminum or titanium or alloys thereof, and provides a low pressure drop and lightweight catalyst, making the catalyst especially well adapted for use in aircraft to abate ozone in cabin air.

Abstract: In a system for treating an exhaust stream, such as the exhaust of an internal combustion engine (10), the exhaust is initially treated by a first catalytic converter (14) and its effluent is cooled in an indirect heat exchanger (18) with an extraneous coolant fluid, i.e., one other than recycled engine exhaust, before introducing the exhaust into a hydrocarbon trap (30) to adsorb hydrocarbons therefrom at least during a cold-start period of engine operation. Such cooling enables utilization of highly efficient adsorbent materials such as activated carbon which otherwise could not be used. Adsorbed hydrocarbons are desorbed from the hydrocarbon trap (30) as the engine exhaust heats up. The exhaust is passed from hydrocarbon trap (30) to a second catalytic converter (34) for oxidation of the hydrocarbons.

Abstract: A combustor for supporting the catalytic combustion of a gaseous carbonaceous fuel/air combustion mixture contains a catalyst zone in which is disposed a catalyst body comprising at least a first and a second catalyst member and further contains a downstream zone where homogeneous combustion occurs. Each catalyst member is comprised of a carrier body having a catalyst material deposited thereon. The first carrier is made of a silica-magnesia-alumina material comprised primarily of cordierite, mullite and corundum and the second carrier is made of a ceramic fiber matrix material comprising ceramic (alumina-boron oxide-silica) fibers in a silicon carbide matrix.