Pechiney Recherche

Centre National De La Recherche Scientifique

Rhone-poulenc Chimie

Marie Prin

Bernard Grindatto

Alex Jourdan

Olivier Touret

Marc-Jacques Ledoux

Jean-Louis Guille

Lionel Bonneau

Benoist Ollivier

Michele Pijolat

Pascal Hervieu

Gerard Baluais

Benoit Ollivier

Michel Soustelle

Cuong Pham Huu

Hugh Dunlop

Geard Baluais

Airy Pierre Lamaze

A catalyst carrier including a surface layer of oxygen-donating oxide, particularly cerine, is disclosed. A catalytic phase deposited on said carrier generally includes platinum and rhodium, thus forming a catalytic system for exhaust pipes, said catalytic phase being readily recoverable by simple leaching.

Metal oxide-coated SiC foam carriers for catalysts, and catalytic systems therefor

Silicon carbide foam useful as a catalyst support has a BET specific surface area of at least 5 m,/g, and a compression strength exceeding 0.2 MPa. The foam is prepared by impreganting an organic foam with a suspension of silicon in a resin containing a cross-linking agent, incompletely cross-linking the resin, carbonizing the foam and resin, and carburizing the silicon.

Silicon carbide foam with high specific surface area and improved mechanical properties

Process for the preparation of metal carbides having a large specific surface from activated carbon foams

SiC foam-based catalyst carrier in the form of a moulded part having walls reinforced with a SiC skin having mechanical characteristics higher than those of the foam, this skin allowing the carrier to be handled and used without damage.

SiC foam catalyst carrier with a reinforced skin and corresponding

A catalyst for chemical and petrochemical reactions and a process for its production. The catalyst comprises an oxide of one of the transition metals, rare earth elements, or actinide elements, e.g., molybdenum, having on its surface carbides and oxycarbides, the core being the metal or the metal oxide. In the process for catalyst production, the reaction gas mixture containing carbon products is passed onto the oxide, leading to a progressive carburization of the surface of the oxide and to a progressive increase in the efficiency of the catalyst.

Preparation of a catalyst from metal oxides by reduction and partial

The invention concerns a process for preparing a silicon carbide foam consisting of attacking a polyurethane foam with an alkaline solution, impregnating it, after rinsing and drying, with a suspension of silicon powder in an organic resin, heating progressively to polymerise the resin, carbonising the polyurethane foam and resin, and finally carburising the silicon contained in the resin suspension by means of the carbon originating from the carbonisation of the foam and resin. The foams obtained are characterised by a high microporosity and a mesoporosity which is variable according to the carburising temperature. The invention finds an application in the manufacture of catalyst carriers for exhaust chambers and filters for diesel engines.

Manufacture of silicon carbide foam from a polyurethane foam impregnated

A process for preparing a silicon carbide foam by impregnating a polyurethane foam with a suspension of silicon powder in an organic resin, heating progressively to polymerize the resin, heating further to carbonize the polyurethane foam and resin, and finally further heating to carburize the silicon contained in the resin suspension by means of carbon obtained from the carbonization of the foam and resin. The foam obtained is characterized by high macroporosity and a mesoporosity which is variable according to the carburizing temperature.

A process for the production of a metal carbide having a BET specific surface area of 10 to 200 m.sup.2 /g, in which a reaction mixture including carbon having a specific surface area of at least 200 m.sup.2 /g and a compound of the metal to be reacted with the carbon which is volatile at 900.degree. C. to 1400.degree. C. is introduced into a reactor, the reactor is scavenged by a flow of inert gas and the reaction mixture is heated under the flow of inert gas at 900.degree. to 1400.degree. C. for a time sufficient to volatilize the metal, reduce the volatilized metal compound to the metal with and carburize the metal by reaction with carbon, forming the metal carbide. The metal carbide formed is cooled under the flow of inert gas.

Process for the production of metal carbides having a large specific

Thermally stable ceric oxide-based compositions, well suited as catalysts/catalyst supports for a wide variety of reactions, notably for the catalytic conversion of exhaust gases emanating from internal combustion engines, comprise particulates of immixture of a major amount of ceric oxide with at least one other metal oxide of magnesium, gallium, boron, scandium, or mixture thereof, and having a specific surface greater than 10 m.sup.2 /g after calcination at 800.degree. C.

Growing community of inventors

Moirans, France

Marie Prin