Abstract: A catalyst comprising at least one porous support, at least some platinum, and at least a second group VIII metal which is different from platinum and iridium, said catalyst having been prepared in accordance with a process comprising a) impregnation of the support with at least one solution containing a platinum precursor, b) activation in a neutral or oxidizing atmosphere, at a temperature of between 120 and 800° C., c) activation in a reducing medium, at a temperature of between 0 and 800° C., d1) impregnation with an aqueous solution and d2) treatment with at least one hydrogen donor compound, at a temperature of less than 200° C., e) the impregnation of the support, which has already been impregnated with the platinum, with at least one solution containing a precursor of said second group VIII metal, and f) activation in a neutral, reducing, or oxidizing atmosphere, at a temperature of between 100 and 800° C.

Abstract: A process for isomerizing an aromatic C8 cut uses a catalyst which comprises: at least one ITQ-6 zeolite; at least one metal from group VIII of the periodic table; at least one binder; optionally, at least one metal selected from the group formed by elements from groups IIIA, IVA and VIIB of the periodic table; and optionally, sulphur.

Abstract: A description is given of a catalyst comprising at least one porous support, at least some platinum, and at least a second group VIII metal which is different from platinum and iridium, said catalyst having been prepared in accordance with a process comprising a) impregnation of the support with at least one solution containing a platinum precursor, b) activation in a neutral or oxidising atmosphere, at a temperature of between 120 and 800° C., c) activation in a reducing medium, at a temperature of between 0 and 800° C., d1) impregnation with an aqueous solution and d2) treatment with at least one hydrogen donor compound, at a temperature of less than 200° C., e) the impregnation of the support, which has already been impregnated with the platinum, with at least one solution containing a precursor of said second group VIII metal, and f) activation in a neutral, reducing, or oxidising atmosphere, at a temperature of between 100 and 800° C.

Abstract: The invention concerns materials for eliminating oxides of nitrogen NO and NO2 present in exhaust gases, in particular from the internal combustion engines of automotive vehicles operating in a medium that is super-stoichiometric in oxidizing agents, which can adsorb oxides of nitrogen then desorb the oxides of nitrogen by elevating the temperature with respect to the adsorption temperature or by passage of a rich mixture, the materials comprising mixed oxides the metals of which are in octahedral co-ordination, with the octahedra connecting together so that the structure generates micropores in the form of channels. The channel width of the materials is such that the sides are composed of 2 and/or 3 octahedra. These materials adsorb oxides of nitrogen by insertion and do not become poisoned in contact with oxides of sulfur and carbon contained in the gases.

Abstract: The invention concerns materials for eliminating oxides of nitrogen NO and NO2 present in exhaust gases, in particular from the internal combustion engines of automotive vehicles operating in a medium that is super-stoichiometric in oxidizing agents, which can adsorb oxides of nitrogen then desorb the oxides of nitrogen by elevating the temperature with respect to the adsorption temperature or by passage of a rich mixture, the materials comprising mixed oxides the metals of which are in octahedral co-ordination, with the octahedral connecting together so that the structure generates micropores in the form of channels. The channel width of the materials is such that the sides are composed of 2 and/or 3 octahedra. These materials adsorb oxides of nitrogen by insertion and do not become poisoned in contact with oxides of sulfur and carbon contained in the gases.

Abstract: The invention concerns materials for eliminating oxides of nitrogen NO and NO2 present in exhaust gases, in particular from the internal combustion engines of automotive vehicles operating in a medium which is super-stoichiometric in oxidising agents, which can adsorb oxides of nitrogen then desorb the oxides of nitrogen by elevating the temperature with respect to the adsorption temperature or by passage of rich mixture, said materials comprising mixed oxides the metals of which are in octahedral coordination, with the octahedra connecting together so that the structure generates micropores in the form of channels. These materials adsorb oxides of nitrogen by insertion and do not become poisoned in contact with oxides of sulphur and carbon contained in the gases. In the presence of a group VIII metal, these materials are capable of eliminating oxides of nitrogen absorded by reduction during passage of a rich mixture.

Abstract: A device for eliminating nitrogen oxides in an exhaust line of a lean-burn internal-combustion engine (1) a NOx trap (3) for trapping the nitrogen oxides, a system for regenerating the nitrogen oxides when the NOx trap is saturated, a hydrocarbon treating catalyst (2) placed upstream from the NOx trap (3), a hydrocarbon injector (4) placed upstream from hydrocarbon treating catalyst (2), a probe (7) for measuring the gas mixture strength. The hydrocarbon treating catalyst (2) is a partial (or controlled) hydrocarbon oxidation catalyst that cooperates with the NOx trap (3) for trapping the nitrogen oxides and that allows to obtain, at the outlet thereof, gases with a low oxygen (O2) concentration and with high carbon monoxide (CO) and hydrogen (H2) concentrations. A control unit is furthermore provided for recording and processing data coming from various detectors and/or stored in order to carry out effective regeneration of the NOx trap (3) without disrupting the smooth running of the engine.

Abstract: The invention concerns materials for adsorbing and desorbing oxides of nitrogen NO and NO2 present in exhaust gases, in particular from the internal combustion engines of automotive vehicles operating in a medium which is super-stoichiometric in oxidizing agents, which can desorb the oxides of nitrogen by elevating the temperature, with respect to an adsorption temperature, the structure of the materials being composed of phosphate tetrahedra and containing at least one element (A) from groups IVB, VB, VIB, VIIB, IVA, optionally at least one element (B) selected from the group formed by alkali elements IA, alkaline-earth elements IIA, rare earths IIIB and transition metals, and optionally at least one metal (C) selected from the group formed by the precious metals of the platinum family (group VIII). These materials are insensitive to the oxides of sulphur and carbon contained in the gas.

Abstract: A combustion catalyst comprising a monolithic substrate, a porous support based on refractory inorganic oxide and an active phase formed by cerium, iron and at least one metal selected from the group formed by palladium and platinum, the content of porous support being between 100 and 400 g per liter of catalyst; the content of cerium being between 0.3 and 20% by weight with respect to the porous support; the content of iron being between 0.01 and 3.5 % of iron by weight with respect to the porous support; and the content of palladium and/or platinum being between 3 and 20 g per liter of catalyst.

Abstract: An IM-5 zeolite that is modified by adding phosphorus that is optionally dealuminified, preferably in aluminosilicic form, and that contains at most 10% by weight of phosphorus, a composition that contains it, its processes for preparation and its application to catalytic cracking of hydrocarbon feedstocks are described.

Abstract: A combustion catalyst comprising a monolithic substrate, a porous support based on refractory inorganic oxide and an active phase formed by cerium, iron and at least one metal selected from the group formed by palladium and platinum, the content of porous support being between 100 and 400 g per liter of catalyst; the content of cerium being between 0.3 and 20% by weight with respect to the porous support; the content of iron being between 0.01 and 3.5% of iron by weight with respect to the porous support; and the content of palladium and/or platinum being between 3 and 20 g per liter of catalyst. The catalyst of the invention is used in particular in processes for the catalytic combustion of hydrocarbons, carbon monoxide, hydrogen or mixtures thereof, in processes involving one or more catalytic stages.

Abstract: The invention concerns a process for reducing emissions of oxides of nitrogen in a medium which is super-stoichiomeitric in oxidising agents, comprising: a) a step for oxidising at least a portion of the oxides of nitrogen in the presence of an oxidation material; b) a step for injecting organic compounds which comprise at least one atom selected from carbon, hydrogen, oxygen and nitrogen; c) a step for adsorbing at least a portion of the organic compounds onto an adsorption material in the form of molecular species and/or carbonaceous residues; d) a step for selective reduction of at least a portion of the oxides of nitrogen to molecular nitrogen by at least a portion of the molecular species and/or carbonaceous residues formed on the adsorption material.

Abstract: The present invention provides a process for reducing oxides of nitrogen to molecular nitrogen in a medium which is superstoichiometric in oxidizing agent using reducing agents in the presence of a catalyst comprising:at least one refractory inorganic oxide at least in part constituted by a zeolite from the group formed by NU-86, NU-87 and EU-1;optionally, at least one element (A) from groups VIB, VIIB, VIII and IB, the transition metals;optionally, at least one element (B) from group VIII, the noble metals comprising platinum, rhodium, ruthenium, iridium and palladium;and optionally at least one element (C) from group IIA, the alkaline-earths and/or group IIIB, the rare earths.

Abstract: A phosphorous-containing zeolite with structural type CON in its aluminosilicate or borosilicate form contains at most 10% by weight of phosphorous. A process for its preparation is described, starting from existing zeolites (SSZ-26, SSZ-33 or CIT-1) or from beta zeolites and an organic structuring agent or template which is 1-N,N,N-trimethyl adamantammonium hydroxide or 2-N,N,N-trimethyl adamantammonium hydroxide. The zeolite is used for catalytic cracking of hydrocarbon feeds.

Abstract: The invention involves the production of a catalyst that contains (1) at least one refractory inorganic oxide support, (2) at least one iron oxide, and (3) at least one cerium oxide, (4) at least one metal A, for example, from Groups VIB, VIIB, VIII, and IB of the Periodic System and, optionally (5) at least one compound of metal B, for example, from Groups IA, IIA, the rare-earths group, and Group IVB of the Periodic System, deposited in the form of a porous layer ("washcoat") on a ceramic or metal substrate:(a) atomizing an aqueous suspension of at least one powder of the refractory inorganic oxide, cerium salt, iron salt, and optionally salt of the metal B; and/or A(b) resuspending the resultant powder and adding any remainder or all of the compound of metal B, as well as, optionally at least one bonding agent and, optionally at least one mineral acid or organic acid;(c) coating a ceramic or metal substrate is coated with the suspension obtained in step (b);(d) calcining the resultant coated substrate;(e)

Abstract: Processes for the catalytic combustion of hydrocarbons, carbon monoxide, hydrogen, or mixtures thereof (processes with one or more catalytic stages) and processes of abating the pollution produced by the exhaust gases of vehicles that run on natural gas using a non-selective oxidation catalyst. The non-selective oxidation catalyst comprises a monolithic substrate, a porous support with a refractory inorganic oxide base and an active phase that consists of cerium, zirconium, iron, and at least one metal that is selected from the group that is formed by palladium and platinum is described; with the porous support content being between 200 and 400 g per liter of catalyst; with the cerium content being between 0.3 and 20% by weight relative to the porous support; with the zirconium content being between 0.3 and 20% by weight relative to the porous support; with the iron content being between 0.01 and 3.

Abstract: A catalyst which is active and selective for the reduction of nitrogen oxides to molecular nitrogen by reducing agents in a medium which is superstoichiometric in oxidizing agents such as carbon monoxide, hydrogen, hydrocarbons, alcohols and other oxygen-containing organic compounds. The active phase of this catalyst is as follows:at least one inorganic refractory oxide;at least one rare earth element (A);at least one alkaline-earth element (B);at least one platinum group metal (C); andat least one silver or gold metal (D).Impregnation of (C) is advantageously followed by heat treatment in a reducing atmosphere.

Abstract: Described is catalyst that is active and selective for reducing to molecular nitrous oxides contained in a superstoichiometric medium of oxidizing agents, said reduction being conducted with agents such as carbon monoxide, hydrogen, hydrocarbons, alcohols, ethers, and other oxidized organic compounds and also with ordinary fuels such as gasolines, gas oils, liquefied gases, and compressed natural gases, whereby said catalyst comprises:at least one refractory inorganic oxide, including alumina;at least one element (A) that belongs to the group of rare earths;at least one element (B) that belongs to groups VIB, VIIB, VIII and IB of transition metals;at least one metal (C) that belongs to the group of precious metals of the platinum family, and optionallyat least one element (D) that belongs to group IIA of alkaline-earths;at least a portion of elements (A) is combined with alumina to form at the surface of the latter a microlayer of rare-earth aluminate.

Abstract: A production process for supported catalysts is described comprising:(a) preparing a coating suspension containing at least one refractory inorganic oxide and at least some of the elements intended to constitute catalytically active phase (A);(b) filling at least part of the open porosity of a support with this suspension;(c) drying the filled support by centrifuging;(d) a thermal treatment of the support to obtain a support coated by a wash coat;(e) optionally impregnating the coated support with a solution containing the rest of, or elements of, catalytically active phase (A); and(f) thermally activating the catalyst.This preparation process is of particular interest in the production of catalysts for treating exhaust gases of internal combustion engines, where the wash coat deposited on a support comprises in particular a refractory inorganic oxide, iron oxide and cerium oxide and, by way of a catalytically active element, at least one noble metal such as platinum, rhodium or palladium.

Abstract: A catalyst for the treatment of exhaust gases from an internal combustion engine comprises a support including a porous layer which latter includes at least one inorganic refractory oxide and an active phase containing at least cerium, iron and platinum, characterized in that said porous layer comprises at least the following percentages by weight0.3% to 4.4% of cerium;0.1% to 3.5% of iron; and0.0003% to 0.04% of platinum; andthe complement to 100% being constituted by at least one inorganic refractory oxide.The catalyst can be used in the treatment of exhaust gases from compression ignition engines, in particular from commercial vehicles with an unladen weight of 3.5 metric tons or more.