An exhaust gas-purifying catalyst includes a support and a catalytic metal supported thereby. The support includes a composite oxide represented by AO.xB.sub.2-C.sub.O.sub.3, wherein A represents at least one of an element having a valence of 1 and an element having a valence of 2, B represents an element having a valence of 3, C represents one or more elements selected from iridium, ruthenium, tantalum, niobium, molybdenum, and tungsten, x represents a numerical value of 1 to 6, and a represents a numerical value greater than 0 and less than 2. The catalytic metal includes one or more precious metals selected from rhodium, palladium, and platinum.

The ammonia synthesis catalyst of the present invention, comprises: a powder of a perovskite oxyhydride having hydride (H.sup.) incorporated therein as a support; and a metal or a metal compound exhibiting a catalytic activity for ammonia synthesis, supported on the support, and the perovskite oxyhydride is represented by ATiO.sub.3-xH.sub.x (wherein A represents Ca, Sr, or Ba, and 0.1x0.6).

The ammonia synthesis catalyst of the present invention, comprises: a powder of a perovskite oxyhydride having hydride (H.sup.) incorporated therein as a support; and a metal or a metal compound exhibiting a catalytic activity for ammonia synthesis, supported on the support, and the perovskite oxyhydride is represented by ATiO.sub.3-xH.sub.x (wherein A represents Ca, Sr, or Ba, and 0.1x0.6).

The effects of different perovskite catalysts, catalytic active materials with a crystal structure of ABO.sub.3, on matrix stabilized combustion in a porous ceramic media are explored. Highly porous silicon carbide ceramics are used as a porous media for a catalytically enhanced matrix stabilized combustion of a lean mixture of methane and air. A stainless steel combustion chamber was designed incorporating a window for direct observation of the flame within the porous media. Perovskite catalytic enhancement of SiC porous matrix with La0.75Sr0.25Fe0.6Cr0.35Ru0.05O3; La0.75Sr0.25Fe0.6Cr0.4O3; La0.75Sr0.25Fe0.95Ru0.05O3; La0.75Sr0.25Cr0.95Ru0.05O3; and LaFe0.95Ru0.05O3, for example, were used to enhance combustion. The flammability limits of the combustion of methane and air were explored using both inert and catalytically enhanced surfaces of the porous ceramic media. By coating the SiC porous media with perovskite catalysts it was possible to lower the minimum stable equivalence ratio.

The effects of different perovskite catalysts, catalytic active materials with a crystal structure of ABO.sub.3, on matrix stabilized combustion in a porous ceramic media are explored. Highly porous silicon carbide ceramics are used as a porous media for a catalytically enhanced matrix stabilized combustion of a lean mixture of methane and air. A stainless steel combustion chamber was designed incorporating a window for direct observation of the flame within the porous media. Perovskite catalytic enhancement of SiC porous matrix with La0.75Sr0.25Fe0.6Cr0.35Ru0.05O3; La0.75Sr0.25Fe0.6Cr0.4O3; La0.75Sr0.25Fe0.95Ru0.05O3; La0.75Sr0.25Cr0.95Ru0.05O3; and LaFe0.95Ru0.05O3, for example, were used to enhance combustion. The flammability limits of the combustion of methane and air were explored using both inert and catalytically enhanced surfaces of the porous ceramic media. By coating the SiC porous media with perovskite catalysts it was possible to lower the minimum stable equivalence ratio.

Captured carbon dioxide is converted into ultra-high purity hydrocarbons, particularly methane. A gas stream containing carbon dioxide is fed to a reactor containing both sorbent and catalyst, until the sorbent portions are substantially saturated with carbon dioxide; non-sorbed species are removed from the first reactor via vacuum and/or purge cycles with high-purity gas; hydrogen gas is introduced to the first reactor to a pressure above ambient; reactor temperature is raised to facilitate desorption of carbon dioxide; and the carbon dioxide is catalytically transformed with the hydrogen gas into methane by recirculating the gas through the reactor. Carbon dioxide adsorption and desorption occur within the sorbent portions, while methanation takes place on the catalytic portions assisted by the sorbent at a temperature substantially consistent with the desorption. Downstream upgrading steps may remove or reduce impurities to produce ultra-high purity methane for chemical vapor deposition or other processes.

Captured carbon dioxide is converted into ultra-high purity hydrocarbons, particularly methane. A gas stream containing carbon dioxide is fed to a reactor containing both sorbent and catalyst, until the sorbent portions are substantially saturated with carbon dioxide; non-sorbed species are removed from the first reactor via vacuum and/or purge cycles with high-purity gas; hydrogen gas is introduced to the first reactor to a pressure above ambient; reactor temperature is raised to facilitate desorption of carbon dioxide; and the carbon dioxide is catalytically transformed with the hydrogen gas into methane by recirculating the gas through the reactor. Carbon dioxide adsorption and desorption occur within the sorbent portions, while methanation takes place on the catalytic portions assisted by the sorbent at a temperature substantially consistent with the desorption. Downstream upgrading steps may remove or reduce impurities to produce ultra-high purity methane for chemical vapor deposition or other processes.

The present disclosure provides a multi-metallic catalyst system comprising at least one support, and at least one promoter component and an active component comprising at least two metals uniformly dispersed on the support. The present disclosure also provides a process for preparing the multi-metallic catalyst system. Further, the present disclosure provides a process for preparing upgraded fuel from biomass. The process is carried out in two steps. In the first step, a biomass slurry is prepared and is heated in the presence of hydrogen and a multi-metallic catalyst that comprises at least one support, at least one promoter component, and an active component comprising at least two metals to obtain crude biofuel as an intermediate product. The intermediate product obtained in the first step is then cooled and filtered to obtain a filtered intermediate product. In the second step, the filtered intermediate product is hydrogenated in the presence of the multi-metallic catalyst to obtain the upgraded fuel. The fuel obtained from the process of the present disclosure is devoid of heteroatoms such as oxygen, nitrogen and sulfur.

The present disclosure provides a multi-metallic catalyst system comprising at least one support, and at least one promoter component and an active component comprising at least two metals uniformly dispersed on the support. The present disclosure also provides a process for preparing the multi-metallic catalyst system. Further, the present disclosure provides a process for preparing upgraded fuel from biomass. The process is carried out in two steps. In the first step, a biomass slurry is prepared and is heated in the presence of hydrogen and a multi-metallic catalyst that comprises at least one support, at least one promoter component, and an active component comprising at least two metals to obtain crude biofuel as an intermediate product. The intermediate product obtained in the first step is then cooled and filtered to obtain a filtered intermediate product. In the second step, the filtered intermediate product is hydrogenated in the presence of the multi-metallic catalyst to obtain the upgraded fuel. The fuel obtained from the process of the present disclosure is devoid of heteroatoms such as oxygen, nitrogen and sulfur.

A process is disclosed for producing ethanol, comprising contacting acetic acid and hydrogen in a reactor in the presence of a catalyst comprising a binder, a mixed oxide, and at least two promoter metals comprising ruthenium and bismuth. The mixed oxide preferably also comprises cobalt and tin.