Abstract: A device for aligning and/or assembling filtering elements, in particular of particulate filter, an installation for assembling a filter from filtering elements incorporating the device, and a method for aligning and/or assembling monolithic filtering elements, in particular for making a particulate filter. The device includes a back plate whereon are set the filtering elements, the back plate being for example fixed on a base plate, and walls laterally foldable upwards by a folding mechanism, such that the filtering elements are mutually maintained tightly when the walls are in an upper position.

Abstract: The invention concerns a structure (11) comprising a filtering member (21) comprising intake conduits (35) for the gases to be filtered, and conduits (37) for extracting the filtered gases, separated from the intake conduits (35) by porous filtering walls (43). The intake conduits (35) emerge into openings (49) for discharging respective residues, provided downstream of the respective intake openings (47). The openings discharging residues (49) of the intake conduits (35) open into a common manifold (25) for receiving solid filtering residues, forming counter-pressure means for the intake conduits (35). Said manifold (25) is isolated from the extracting conduits (37). The invention is applicable to particulate filters for exhaust gases of a motor vehicle diesel engine.

Abstract: The invention concerns a structure (11) comprising a filtering member (21) comprising intake conduits (35) for the gases to be filtered, and conduits (37) for extracting the filtered gases, separated from the intake conduits (35) by porous filtering walls (43). The intake conduits (35) emerge into openings (49) for discharging respective residues, provided downstream of the respective intake openings (47). The openings discharging residues (49) of the intake conduits (35) open into a common manifold (25) for receiving solid filtering residues, forming counter-pressure means for the intake conduits (35). Said manifold (25) is isolated from the extracting conduits (37). The invention is applicable to particulate filters for exhaust gases of a motor vehicle diesel engine.

Abstract: The invention relates to a filtration structure (11) consisting of: first and second filtration elements (15A, 15B) which comprise respectively a first face and a second face (24A, 24B), said faces being disposed opposite one another; and a connecting joint (17) which extends between the faces (24A, 24B) and connects same. The aforementioned joint (17) comprises a binder (41) and reinforcing means (43) which are embedded therein. The reinforcing means (43) comprise an open-work reinforcing member having an autonomous coherence and comprising an essentially-flat active part (45). The invention is suitable for particle filters for the exhaust gases from an internal combustion engine.

Abstract: This invention is a high strength, thermal shock resistant, high purity siliconized silicon carbide material made from siliconizing a converted graphite SiC body having at least 71 vol % silicon carbide therein.

Abstract: This invention is a high strength, thermal shock resistant, high purity siliconized silicon carbide material made from siliconizing a converted graphite SiC body having at least 71 vol % silicon carbide therein.

Abstract: This invention relates to a siliconized silicon carbide-base composite comprising at least about 71 vol % converted-graphite SiC matrix having open porosity, wherein the open porosity of the matrix is essentially filled with silicon, and the composite has a total metallic impurity content of no more than 10 ppm.

Abstract: The disclosure teaches a method for obtaining porous solids of refractory carbide with a large specific surface area. An exclusively organic, polymeric and/or copolymerizable compound, for example a resin, which can be coked and to provide a solid carbon skeleton, is mixed with a powder of metal, or metalloid, or a compound thereof which can be reduced by carbon. The mixture is shaped, the organic compound is cross-linked or hardened, and the compound is heat treated from 500.degree. to 1000.degree. C. to coke it, then heat treated to carburize it.

Abstract: Abrasive and/or refractory products comprising at least one compound from the group of oxynitrides of one or more metals or metalloids (such as Al, Mg, alkaline earth metals, Si, Ti or Zr) and obtained by melting and solidification.

Abstract: Process for direct nitriding of metals of relatively low melting point with the aid of a nitrogen-containing gas, in which a powder of at least one of the metals is mixed with a refractory powder, the mixture is heated under an atmosphere of nitrogen-containing gas at atmospheric pressure until the start of a rapid and exothermic nitriding reaction, and this reaction, which proceeds at a temperature generally higher than that of the melting point of the metals without apparent melting being observed, is allowed to proceed until all of the metals have been consumed, in order to obtain a highly porous solid mass which is easy to grind and is based on metal nitrides or metal oxynitrides.

Abstract: A porous refractory carbide with a large specific surface area is disclosed. The refractory carbide has a skeleton of metallic or metalloid refractory carbide and has a bimodal open porosity with a group of pores of 1 to 100 microns and a group of pores smaller than 0.1 micron.

Abstract: The invention relates to a catalytic system and to a method of producing such a system.The catalytic system consists of a support on which the catalytically active product is deposited. The support has mechanical or physical properties which are of interest in terms of the required working conditions, but a poor specific surface area. The catalytically active product, a metallic carbide, is obtained by coating the support in a suspension of a reducible compound of the metal in a solution of an organic compound, carbonizing this compound, reducing the metallic compound and carburizing the metal. The carbide thus obtained has a high specific surface area.Preferably, the support consists of silicon carbide produced by carbonizing a paste containing silicon, carbon and an organic resin.The invention is applicable to any form of catalyst but in particular to the monolithic catalysts intended for treating exhaust gases.

Abstract: The invention concerns a multiphase alumina-based material formed by a matrix of corundum in which microcrystalline phases of aluminium oxycarbide, aluminium oxynitride and aluminium oxycarbonitride are homogeneously dispersed. The combined carbon content is between 0.05 and 5% and the combined nitrogen content is from 0.05 to 5% by weight. The material can be produced by the controlled injection of carbon and nitrogen into a molten alumina bath. The material is used for abrasive products and refractory products with high levels of performance.

Abstract: The invention is directed to a process for the production of fine grains of silicon carbide which are formed by an agglomerate of submicronic grains having a specific surface area that is at least 100 m.sup.2 .multidot.g.sup.-1, which are intended in particular to serve as a carrier for catalysts for petrochemistry, and for catalytic reactions at elevated temperature which can attain 1000.degree. C., the process comprising reacting vapors of silicon monoxide SiO on carbon, being characterized by: generating vapors of SiO in a first reaction zone by heating a mixture SiO.sub.2 +Si at a temperature of between 1100.degree. and 1400.degree. C., under a pressure of between 0.1 and 1.5 hPa; and, in a second reaction zone, contacting the SiO vapors with reactive carbon in the divided state with a specific surface area that is at least equal to 200 m.sup.2 .multidot.g.sup.-1 at a temperature of between 1100.degree. and 1400.degree. C.

Abstract: The invention relates to a process for the preparation of silicon carbide whiskers by the reaction, in a non-oxidizing atmosphere, at a temperature of at least 1300.degree. C., of a charge composed of a mixture of carbon black and a source of silicon oxide, in which process the carbon black has an oxidability rate (measured by heating in air for 30 minutes at 600.degree. C.) of at least 85%, the silicon oxide source has a grain size of less than 100 .mu.m and the rate of rise in temperature between 1300.degree. and 1600.degree. C. is less than 30.degree. C.min.sup.-1 per minute if a static atmosphere prevails and at most 25.degree. C.min.sup.-1 if gas percolated. A stage of from 5 min to 5 h at 1600.degree. C. is optionally carried out.The carbon is preferably introduced into the reaction mixture in an over-stoichiometric quantity relative to the silica.The excess carbon is removed at the end of the reaction by oxidation in air at about 600.degree. C.