Nissan Motor Company Limited

Renault S.a.s.

Kazuyuki Shiratori

Masanori Nakamura

Katsuo Suga

Hironori Wakamatsu

Hirofumi Yasuda

Hiroto Kikuchi

Toru Sekiba

Jun Ikezawa

Tetsuro Naito

Toshiharu Miyamura

Yoshiaki Hiramoto

Makoto Aoyama

Hideaki Morisaka

Haruhiko Shibayama

Kenji Uesugi

Masanori Nakamaura

Naito Tetsuro

An exhaust gas purifying catalyst comprises: a plurality of catalyst units which contain anchor particles that support noble metal particles; and an enclosure material that internally contains the plurality of catalyst units and separates the catalyst units from each other. Both the anchor particles and the enclosure material contain an alkali element and/or an alkaline earth element. Due to this configuration, this exhaust gas purifying catalyst is capable of maintaining the exhaust gas purification performance by suppressing agglomeration of the noble metal particles even in cases where the ambient temperature is high.

Exhaust gas purifying catalyst and method for producing same

An object is to maintain an effect of enhancing activity of noble metal particles by transition metal without increasing production cost and an environmental load. An exhaust gas purifying catalystis composed of: noble metal particles; first compoundswhich contact the noble metal particlesand suppress movement of the noble metal particles; and second compoundswhich contain the noble metal particlesand the first compounds, suppress the movement of the noble metal particles, and suppress coagulation of the first compoundsfollowing mutual contact of the first compounds, wherein the first compoundssupport the noble metal particles, and simplexes or aggregates of the first compoundssupporting the noble metal particlesare included in section partitioned by the second compounds

Exhaust gas purifying catalyst and production method thereof

An exhaust gas purifying catalyst includes: a catalyst particle unit having at least noble metal with a catalytic function, first oxides on which the catalyst noble metal is supported, and second oxides covering the first oxides on which the noble metal is supported. In catalyst powder formed of an aggregate of plural pieces of the catalyst particle units, at least one type of compounds selected from the group consisting of a transition element, an alkali earth metal element, an alkali metal element, and a rare earth element, which is a promoter component, are contained.

Exhaust gas purifying catalyst and producing method thereof

An exhaust gas purifying catalyst is constituted by: noble metal particles (); first compounds () which support the noble metal particles (); second compounds () different in type from the first compounds (); and oxides () which surround the noble metal particles (), the first compounds () and the second compounds (). A median diameter of the first compounds () and a median diameter of the second compounds () satisfy a relationship of a following inequality:median diameter of first compounds&#x3c;median diameter of second compounds.

Exhaust gas purifying catalyst

An exhaust gas purifying catalyst () according to the present invention includes noble metal particles (), a first compound () supporting the noble metal particles (), and a second compound () disposed not in contact with the noble metal particles () and having an oxygen storage capacity. An average distance between the first compound () and the second compound () is between 5 nm and 300 nm.

Exhaust gas purifying catalyst and method for manufacturing the same

An exhaust gas purifying catalyst () is composed of: a noble metal (); a first compound (); and a second compound (). The noble metal () is supported on the first compound (). The exhaust gas purifying catalyst () includes units having a structure in which the first compound () supporting the noble metal () is surrounded by the second compound (), and the first compound () supporting the noble metal () is isolated from one another by the second compound (). The noble metal () is one or more selected from [Pt, Pd and Rh], the first compound () contains Ti as a main component, and the second compound () contains, as a main component, one or more selected from [Al and Si].

Exhaust gas purifying catalyst and method for producing the same

Disclosed is an exhaust gas purifying catalyst exhibiting excellent purification performance for a long period of time by suppressing coagulation of a noble metal. A catalyst powder comprises a noble metal and first and second compounds. In the catalyst powder, the first compound carries the noble metal and is separated from another first compound carrying a noble metal by the second compound. At least one catalyst layer comprising the catalyst powder is formed on an inner surface of a substrate. The catalyst layer has fine pores. A fine pore volume of fine pores having a fine pore diameter of greater than 0.1 &#x3bc;m to less than or equal to 1 &#x3bc;m is 10% to 60% of the fine pore volume of fine pores having a pore diameter of 1.0 &#x3bc;m or less.

Exhaust gas purifying catalyst and method of producing the same

An exhaust gas purifying catalyst including: a plurality of first compoundswhich have precious metal particlessupported thereon and are formed into a particle shape; and second compoundswhich are arranged among the plurality of first compoundsand separate the first compoundsfrom one another, wherein pore volumes of the precious metal particles, the first compoundsand the second compoundsare 0.24 to 0.8 cm/g.

An exhaust gas purifying catalyst including: rhodium particles having catalytic activity; compound particles which are formed on peripheries of the rhodium particles and support the rhodium particles; and oxides which are formed on peripheries of the compound particles and suppress coagulation of the compounds.

A catalyst producing method comprises preparing reverse micellar solution including an aqueous solution containing at least a noble metal element as a catalytic active component, and carrying the catalytic active component by a substrate to establish them into a catalyst precursor; and spraying the emulsion solution containing the catalyst precursor in an inert gas atmosphere to obtain a dried catalyst precursor, and firing the obtained dried catalyst precursor in an air atmosphere. A catalyst is obtained by the catalyst producing method.

Catalyst and producing method thereof

A method of producing catalyst powder of the present invention has a step of precipitating a transition metal particle and a base-metal compound in a reversed micelle substantially simultaneously, and a step of precipitating a noble metal particle in the reversed micelle. By this method, it is possible to obtain catalyst powder which restricts an aggregation of noble metal particles even at the high temperature and is excellent in the catalytic activity.

Catalyst powder, exhaust gas purifying catalyst, and method of producing the catalyst powder

A method of producing catalyst powder of the present invention has a step of precipitating a carrier in a reversed micelle, and a step of precipitating at least one of a noble metal particle and a transition metal particle in the reversed micelle in which the carrier is precipitated. By this method, it is possible to obtain catalyst powder excellent in heat resistance and high in the catalytic activity.

Catalyst powder, method of producing the catalyst powder, and exhaust gas purifying catalyst

A catalyst which suppresses aggregation of metal particles and which has superior heat resistance. In the catalyst, metal particles are supported by a surface of a carrier while being partially embedded therein.

Catalyst, exhaust gas purification catalyst, and method for manufacturing same

A method of producing catalyst powder of the present invention has a step of precipitating any one of a noble metal particle () and a transition metal particle () in a reversed micelle (); a step of precipitating, in the reversed micelle () in which any one of the noble metal particle () and the transition metal particle () is precipitated, a porous support material () which supports the noble metal particle () and the transition metal particle (); and a step of precipitating the other of the noble metal particle () and the transition metal particle () in the reversed micelle () in which any one of the noble metal particle ().

Growing community of inventors

Yokohama, Japan

Kazuyuki Shiratori