Abstract: A system for exhaust gas purification disposed in the exhaust pipe of an internal combustion engine, includes (1) an adsorbent comprising a monolithic carrier and (2) an adsorbent component having a hydrocarbon adsorptivity, loaded on the carrier, and a catalyst comprising a monolithic carrier and a catalyst component loaded on the carrier, having a purifiability for the harmful substances present in the exhaust gas emitted from the engine. The catalyst is provided downstream of the adsorbent in the flow direction of the exhaust and it can remove the hydrocarbons generated during engine cold gas. The adsorbent has a sectional shape satisfying the following relation: 1.2≦(major axis)/(minor axis)≦6.5 This system enables the desorption of hydrocarbons from the adsorbent in a longer time and can remove the hydrocarbon generated during engine cold start at a higher purification ratio.

Abstract: A catalyst for exhaust gas purification is capable of purifying the hydrocarbons, nitrogen oxides and carbon monoxide present in the exhaust gas discharged from an internal combustion engine. The catalyst has a monolithic carrier and a catalyst layer containing Pd, Ba and a heat-resistant inorganic oxide, formed on the carrier. The amount of Pd supported on monolithic carrier is 100-300 g per ft3 of monolithic carrier (3.53×10−3 to 1.06×10−2 g per cc of monolithic carrier), the amount of Ba supported on monolithic carrier is 0.010-0.060 g per cc of monolithic carrier in terms of BaO, and the weight ratio of Pd and Ba as expressed as BaO is 1:2 to 1:10. This catalyst for exhaust gas purification is superior particularly in hydrocarbon purification for a low-temperature fuel-rich exhaust gas (such as exhaust gas emitted during cold start) of automobile.

Abstract: A catalyst for exhaust gas purification is capable of purifying the hydrocarbons, nitrogen oxides and carbon monoxide present in the exhaust gas discharged from an internal combustion engine. The catalyst has a monolithic carrier and a catalyst layer containing Pd, Ba and a heat-resistant inorganic oxide, formed on the carrier. The amount of Pd supported on monolithic carrier is 100-300 g per ft3 of monolithic carrier (3.53×10−3 to 1.06×10−2 g per cc of monolithic carrier), the amount of Ba supported on monolithic carrier is 0.010-0.060 g per cc of monolithic carrier in terms of BaO, and the weight ratio of Pd and Ba as expressed as BaO is 1:2 to 1:10. This catalyst for exhaust gas purification is superior particularly in hydrocarbon purification for a low-temperature fuel-rich exhaust gas (such as exhaust gas emitted during cold start) of automobile.

Abstract: A system for exhaust gas purification disposed in the exhaust pipe of an internal combustion engine, includes an adsorbent formed by loading, on a monolithic carrier, (1) a zeolite containing at least one kind of ion of an element having an electronegativity of 1.40 or more and (2) a catalyst material formed by loading at least one kind of noble metal selected from Pt, Pd and Rh on a heat-resistant inorganic oxide, and at least one loaded carrier formed by loading, on a monolithic carrier, a catalyst component having a purifiability for the harmful substances present in the exhaust gas emitted from the engine and/or an adsorbent component having an adsorptivity for the hydrocarbons also present in the exhaust gas, the loaded carrier being provided upstream of the adsorbent in the flow direction of the exhaust gas and having a total volume of 0.6 l or more.

Abstract: A system for exhaust gas purification disposed in the exhaust pipe of an internal combustion engine, includes an adsorbent comprising a monolithic carrier and an adsorbent component having a hydrocarbon adsorptivity, loaded on the carrier, and a catalyst comprising a monolithic carrier and a catalyst component loaded on the carrier, having a purifiability for the harmful substances present in the exhaust gas emitted from the engine, the catalyst being provided downstream of the adsorbent in the flow direction of the exhaust gas.

Abstract: A catalyst for exhaust gas purification is capable of purifying the hydrocarbons, nitrogen oxides and carbon monoxide present in the exhaust gas discharged from an internal combustion engine. The catalyst has a carrier and a catalyst layer containing at least one kind of noble metal, Ba and Cs, formed on the carrier. This catalyst for exhaust gas purification is improved in hydrocarbon purification ability for a low-temperature fuel-rich exhaust gas (such as exhaust gas emitted during cold start) of automobile.

Abstract: A method for exhaust gas purification using an exhaust gas purification system including (a) an adsorbent for adsorbing hydrocarbons in internal combustion engine exhaust gas provided in the engine exhaust pipe, (b) at least one catalyst for reducing harmful substances present in the exhaust gas, provided in the exhaust pipe upstream of the adsorbent in the flow direction of the exhaust gas, (c) at least one catalyst for reducing harmful substances present in the exhaust gas, provided in the exhaust pipe down-stream of the adsorbent in the flow direction of the exhaust gas, (d) a first inlet for introduction of secondary air into exhaust gas, formed in the exhaust pipe upstream of the most downstream catalyst of the catalyst (b), and (e) a second inlet for introduction of secondary air into exhaust gas, formed in the exhaust pipe between the catalyst (b) and the most downstream catalyst of the catalyst (c).

Abstract: A system for exhaust gas purification disposed in the exhaust pipe of an internal combustion engine, includes followings (i) a catalyst giving an excellent light-off performance at low temperatures, including a carrier and a catalyst layer supported thereon, the catalyst layer including a precious metal and a substance having an electron donatability and/or a nitrogen dioxide absorbability and releasability, and (ii) an adsorbent comprising a carrier and an adsorbent layer having a hydrocarbon adsorbability, supported on the carrier. This system for exhaust gas purification can effectively purify the harmful substances contained in the exhaust gases discharged from internal combustion engines of automobiles, etc., particularly the hydrocarbons discharged in a large amount from a gasoline engine during cold start.

Abstract: A heat-resistant metallic monolith manufactured by forming metal powders into a honeycomb structure and by sintering the structure, a heat-resistant metal oxide coated on the surface of the cell walls and that of the pores thereof. Such a heat-resistant metallic monolith is manufactured by mixing metal powders, an organic binder and water to prepare a mixture, by forming the mixture into a shape of a desired honeycomb configuration, by sintering the shape in a non-oxidizing atmosphere at a temperature between 1000.degree. and 145.degree. C. and then by coating a heat-resistant metal oxide on a surface of the cell walls and that of the pores of the obtained sintered body.

Abstract: A sintered metal body is disclosed of composition consisting essentially of in weight percent about 5 to 40 Cr, about 2 to 30 Al, 0 to about 5 special metal, 0 to about 4 rare earth oxide additive, and the balance Fe group metal and unavoidable impurities,the composition including at least one component selected from component A and/or component B, component A being special metal, and component B being at least an effective amount of rare earth oxide additive,the special metal being a first special metal component, and optionally, a second special metal component when rare earth oxide additive is 0, the first special metal component consisting of at least one of: Y, lanthanides, Zr, Hf, Ti, Si, and B, and the second special metal component consisting of at least one of: alkaline earth metal, Cu, and Sn, and the special metal being a third special metal component when rare earth oxide additive is >0, the third special metal component consisting of at least one of Y, lanthanides, Zr, Hf, Ti, Si, alkaline ear

Abstract: A heat-resistant metallic monolith, manufactured by forming metal powders into a honeycomb structure and by sintering the structure, has a heat-resistant metal oxide coated on the surface of the cell walls and that of the pores thereof. Such a heat-resistant metallic monolith is manufactured by mixing metal powders, an organic binder and water to prepare a mixture, by forming the mixture into a shape of a desired honeycomb configuration, by sintering the shape in a non-oxidizing atmosphere at a temperature between 1000.degree. and 1450.degree. C. and then by coating a heat-resistant metal oxide on a surface of the cell walls and that of the pores of the obtained sintered body.

Abstract: In a catalytic converter operating method according to the present invention, a heater is energized at a predetermined power level or above and thereby heated substantially concurrently with the operation of an engine. During the heating, an oxidizing gas is introduced into the catalytic converter. When the temperature of the heater exceeds a value at which a main catalyst of the catalytic converter or a light-off catalyst carried on the heater functions, the power level is reduced by an output adjuster and supply of the oxidizing gas is suspended.

Abstract: A honeycomb heater having integrally formed and/or integrally sintered electrodes constructed of a metallic honeycomb structure having a desired honeycomb configuration, and metallic electrodes which are integrally sintered with the honeycomb structure at predetermined positions thereon. The honeycomb heater having integrally sintered electrodes is manufactured by joining or contacting the electrode-like formed bodies to the formed honeycomb body, and then by sintering the formed honeycomb body with the electrode-like formed bodies attached or contacted thereto. The electrodes are made of the same material as that of the honeycomb body, or of a material having an electric resistance lower than that of the material comprising the honeycomb body.

Abstract: The catalytic converter includes a first flow passage for an automotive exhaust gas and a second flow passage disposed parallel to the first flow passage to bypass the exhaust gas therethrough. The first flow passage contains a honeycomb heater or a heater catalyst which comprises a honeycomb heater with a catalyst carried thereon. At the beginning of an operation of any engine, the exhaust gas whose temperature is low is caused to flow through the first flow passage. When the temperature of the exhaust gas exceeds a predetermined value, the flow passage is switched from the first passage to the second flow passage.

Abstract: A catalytic converter suitable for use in controlling automotive exhaust emissions including honeycomb heaters which are respectively disposed upstream and downstream of a main monolithic catalyst. Each honeycomb heater includes a honeycomb structure with at least two electrodes provided thereon to supply a current to the honeycomb structure.

Abstract: A resistance adjusting type heater including a honeycomb structure with at least two electrodes provided thereon to supply a current to the honeycomb structure and with resistance adjusting elements provided between the electrodes. The resistance adjusting elements are formed such that a cross-section of a heating portion of the heater is substantially the same as that of a main monolithic catalyst. A catalytic converter includes the resistance adjusting heater which is disposed upstream of a main monolithic catalyst or between main monolithic catalysts. Also, the catalytic converter includes a resistance adjusting heater which is disposed downstream of a main monolithic catalyst. This resistance adjusting heater comprises a honeycomb structure with a catalyst carried thereon, with at least two electrodes provided thereon to supply a current to the honeycomb structure and with a resistance adjusting elements provided between the electrodes.

Abstract: A catalytic converter suitable for use in controlling automotive exhaust emissions including a honeycomb heater disposed downstream of a main monolithic catalyst or between main monolithic catalysts. The honeycomb heater includes a honeycomb structure with a catalyst carried thereon and with at least two electrodes provided thereon to supply a current thereto. A catalytic converter also includes a monolith catalyst for ignition which is disposed downstream of the honeycomb heater. A catalytic converter includes, in place of the honeycomb heater and the monolithic catalyst, a module which is composed of a catalyzed light-off honeycomb heater or of a honeycomb heater and a light-off monolithic catalyst. The module is removably disposed upstream or downstream of a main monolithic catalyst, or between main monolithic catalysts.

Abstract: In a catalytic converter operating method according to the present invention, a heater is energized at a predetermined power level or above and thereby heated substantially concurrently with the operation of an engine. During the heating, an oxidizing gas is introduced into the catalytic converter. When the temperature of the heater exceeds a value at which a main catalyst of the catalytic converter or light-off catalyst carried on the heater functions, the power level is reduced by an output adjuster and supply of the oxidizing gas is suspended.

Abstract: A resistance adjusting type heater has a honeycomb structure having a large number of passages, at least two electrodes to enable electrical heating of the honeycomb structure provided on the honeycomb structure, and a resistance adjusting means, a slit, provided between the electrodes. The thicknesses of passage walls at the portions of the honeycomb structure at which electricity flows at a very high density are increased with a conductive material to prevent the abnormal heat generation at the portions of the honeycomb structure.

Abstract: A resistance adjusting type heater including a honeycomb structure having a large number of passages, at last two electrodes for energizing the honeycomb structure, and a resistance adjusting mechanism such as a slit provided between the electrodes to heat the gas flowing through the passages formed in the honeycomb structure. A catalytic converter includes a main monolith catalyst and the above-described heater placed adjacent to and upstream of the main monolith catalyst. A catalytic converter includes a honeycomb structure having a large number of passages, a catalyst carried on the honeycomb structure, at least two electrodes for energizing the honeycomb structure, and a resistance adjusting mechanism provided between the electrodes. A catalytic converter includes a main monolith catalyst, and a heater placed adjacent to and upstream of the main monolith catalyst.