A method of hydrogenating unsaturated compound with multi-carboxylic acid groups is provided, which includes introducing hydrogen to an unsaturated compound with multi-carboxylic acid groups in the presence of a catalyst to hydrogenate the alkene or alkyne group of the unsaturated compound with multi-carboxylic acid groups without hydrogenating the carboxylic acid groups of the unsaturated compound with multi-carboxylic acid groups. The catalyst includes a support, and palladium and metal oxide loaded on the support.

Provided is a method of preparing an intermetallic catalyst which includes applying ultrasonic wave to a precursor mixture solution including a noble metal precursor, a transition metal precursor, and a carbon support having an average pore size of about 6 nm to about 15 nm and a specific surface area of about 200 m.sup.2/g to about 2000 m.sup.2/g to form alloy particles in pores of the carbon support, and annealing the alloy particles in the pores of the carbon support to form intermetallic alloy particles.

The present invention relates to diesel oxidation catalyst compositions and catalyst articles, wherein the compositions and articles include a plurality of platinum group nanoparticles substantially in fully reduced form, wherein the nanoparticles have an average particle size of about 1 to about 10 nm and at least about 90% of the nanoparticles have a particle size of +/− about 2 nm of the average particle size. Such compositions can further include a refractory metal oxide material, wherein the nanoparticles and refractory metal oxide material can be combined within the same coating on a substrate or can be applied sequentially on a substrate. The nanoparticles can advantageously be substantially free of halides, alkali metals, alkaline earth metals, sulfur compounds, and boron compounds. Methods of preparing and using such compositions and catalyst articles (e.g., for the treatment of diesel exhaust gas streams) are also provided herein.

Direct conversion of syngas to light olefins is carried out in a fixed bed or a moving bed reactor with a composite catalyst A+B. The active ingredient of catalyst A is active metal oxide; and catalyst B is one or more than one of zeolite of CHA and AEI structures or metal modified CHA and/or AEI zeolite. A spacing between geometric centers of the active metal oxide of the catalyst A and the particle of the catalyst B is 5 m-40 mm. A spacing between axes of the particles is preferably 100 m-5 mm, and more preferably 200 m-4 mm. A weight ratio of the active ingredients in the catalyst A and the catalyst B is within a range of 0.1-20 times, and preferably 0.3-5.

Direct conversion of syngas to light olefins is carried out in a fixed bed or a moving bed reactor with a composite catalyst A+B. The active ingredient of catalyst A is active metal oxide; and catalyst B is one or more than one of zeolite of CHA and AEI structures or metal modified CHA and/or AEI zeolite. A spacing between geometric centers of the active metal oxide of the catalyst A and the particle of the catalyst B is 5 m-40 mm. A spacing between axes of the particles is preferably 100 m-5 mm, and more preferably 200 m-4 mm. A weight ratio of the active ingredients in the catalyst A and the catalyst B is within a range of 0.1-20 times, and preferably 0.3-5.

Metal oxide catalysts comprising various dopants are provided. The catalysts are useful as heterogenous catalysts in a variety of catalytic reactions, for example, the oxidative coupling of methane to C2 hydrocarbons such as ethane and ethylene. Related methods for use and manufacture of the same are also disclosed.

Metal oxide catalysts comprising various dopants are provided. The catalysts are useful as heterogenous catalysts in a variety of catalytic reactions, for example, the oxidative coupling of methane to C2 hydrocarbons such as ethane and ethylene. Related methods for use and manufacture of the same are also disclosed.

Metal oxide catalysts comprising various dopants are provided. The catalysts are useful as heterogenous catalysts in a variety of catalytic reactions, for example, the oxidative coupling of methane to C2 hydrocarbons such as ethane and ethylene. Related methods for use and manufacture of the same are also disclosed.

Metal oxide catalysts comprising various dopants are provided. The catalysts are useful as heterogenous catalysts in a variety of catalytic reactions, for example, the oxidative coupling of methane to C2 hydrocarbons such as ethane and ethylene. Related methods for use and manufacture of the same are also disclosed.

Water electrolyzer comprising a membrane having first and second opposed major surfaces, a thickness extending between the first and second major surfaces, and first, second, and third regions equally spaced across the thickness, wherein the first region is the closest region to the first major surface, wherein the second region is the closest region to the second major surface, wherein the third region is located between the first and second regions, wherein the first and third regions are each essentially free of both metallic Pt and Pt oxide, and wherein the second region comprises at least one of metallic Pt or Pt oxide; a cathode comprising a first catalyst on the first major surface of the membrane; and an anode comprising a second catalyst on the second major surface of the membrane.