Disclosed is a catalyst which can be used in the process for producing hydrogen by decomposing ammonia, can generate heat efficiently in the interior of a reactor without requiring excessive heating the reactor externally, and can decompose ammonia efficiently and steadily by utilizing the heat to produce hydrogen. Also disclosed is a technique for producing hydrogen by decomposing ammonia efficiently utilizing the catalyst. Specifically disclosed is a catalyst for use in the production of hydrogen, which is characterized by comprising an ammonia-combusting catalytic component and an ammonia-decomposing catalytic component. Also specifically disclosed is a catalyst for use in the production of hydrogen, which is characterized by comprising at least one metal element selected from the group consisting of cobalt, iron, nickel and molybdenum.

An exhaust gas-purifying three-way catalyst containing: (i) base material particles of a Nd-solid dissolved zirconia-based complex oxide comprising Nd and Zr as constituent metal elements in the following mass proportions: TABLE-US-00001 ZrO.sub.2 50 to 75% by mass; and Nd.sub.2O.sub.3 25 to 50% by mass, in terms of oxides; and (ii) Pd catalyst particles supported on the base material particles, wherein the Nd-solid dissolved zirconia-based complex oxide further contains at least one or more rare earth elements selected from the group consisting of yttrium, scandium, lanthanum, and praseodymium, as a constituent metal element, in an amount of a total of more than 0% by mass to 20% by mass or less in terms of an oxide.

Catalyst compositions comprising a zeolite and a mesoporous support or binder are disclosed. The mesoporous support or binder comprises a mesoporous metal oxide having a particle diameter of greater than or equal to 20 m at 50% of the cumulative pore size distribution (d50). Also disclosed are processes for producing a mono-alkylated aromatic compound (e.g., ethylbenzene or cumene) which exhibit improved yield of the mono-alkylated aromatic compound using alkylation catalysts comprising one or more of these catalyst compositions.

A method for producing biodiesel using a sulfonated, carbonaceous catalyst produced from rice husk, Moringa seeds, or algae biomass, a method for producing the catalyst, and the catalyst itself.

A four-way conversion catalyst for treating a gasoline engine exhaust gas has a porous wall flow filter substrate with an inlet end, outlet end, substrate axial length extending between the inlet and outlet end, and passages defined by porous internal walls of the substrate, the passages having inlet passages with an open inlet and closed outlet, and outlet passages having a closed inlet and open outlet. The internal wall pores have a three-way conversion catalytic in-wall coating with an oxygen storage compound and a platinum group metal supported on a refractory metal oxide. On at least a portion of the internal wall surface defining the interface between the internal walls and the passages, the catalyst has a porous on-wall coating from the internal wall surface to the passage. The coating has porous oxidic compound and platinum group metal content of 0 to 0.001 wt. %, of the total coating weight.

High surface area metal catalysts, and methods of making and using the same, are described.

Provided are an oxovanadium phosphate catalyst, and a preparation method and an application therefor. The method includes: 1) mixing and reacting a vanadium source, a choline chloride-organic carboxylic acid eutectic solvent, and alcohol; 2) mixing the obtained reaction product with a phosphorus source, raising the temperature to a temperature higher than the melting point of the eutectic solvent, and continuing the reaction to obtain an oxovanadium phosphate precursor; and 3) calcining to obtain the oxovanadium phosphate catalyst. The alcohol is: benzyl alcohol or a mixture of C.sub.3-C.sub.8 monohydric alcohol and benzyl alcohol. The present method uses a green and inexpensive eutectic solvent to strengthen the preparation of oxovanadium phosphate catalyst, avoids the disadvantages of the prior art, and overcoming the problems of low yield and poor selectivity when used in a reaction to prepare maleic anhydride by catalytic n-butane selective oxidisation.

Disclosed herein are methods, systems, and compositions for providing catalysts for tail gas clean up in sulfur recovery operations. Aspects of the disclosure involve obtaining catalyst that was used in a first process, which is not a tailgas treating process and then using the so-obtained catalyst in a tailgas treating process. For example, the catalyst may originally be a hydroprocessing catalyst. A beneficial aspect of the disclosed methods and systems is that the re-use of spent hydroprocessing catalyst reduces hazardous waste generation by operators from spent catalyst disposal. Ultimately, this helps reduce the environmental impact of the catalyst life cycle. The disclosed methods and systems also provide an economically attractive source of high-performance catalyst for tailgas treatment, which benefits the spent catalyst generator, the catalyst provider, and the catalyst consumer.

A ferrite catalyst for oxidative dehydrogenation and a method of preparing the same. The ferrite catalyst is prepared using an epoxide-based sol-gel method, wherein a step of burning includes a first burning step, in which burning is performed at a temperature of 70 to 200 C.; and a second burning step, in which burning is performed after the temperature is raised from a temperature in the range of greater than 200 C. to 250 C. to a temperature in the range of 600 to 900 C.

The present invention concerns a process for the production of metal doped cerium compositions comprising a cerium oxide and a metal oxide by precipitation. The invention also concerns metal doped cerium compositions providing high crystallites size and exhibiting high thermal stabilities, which may be used as a catalytic support or for polishing applications.