A method to regenerate and reactivate catalysts used for a carbon and syngas production reaction including a DRM or CARGEN reaction is developed. Carbon dioxide (CO.sub.2) is used as the regeneration and activation media. This method of a single step regeneration and activation using CO.sub.2 is more effective than the existing conventional two-step process that includes separate reduction and oxidation steps. This method produces pure carbon monoxide (CO) as a byproduct from the regeneration process by utilizing CO.sub.2 and carbon.

A method to regenerate and reactivate catalysts used for a carbon and syngas production reaction including a DRM or CARGEN reaction is developed. Carbon dioxide (CO.sub.2) is used as the regeneration and activation media. This method of a single step regeneration and activation using CO.sub.2 is more effective than the existing conventional two-step process that includes separate reduction and oxidation steps. This method produces pure carbon monoxide (CO) as a byproduct from the regeneration process by utilizing CO.sub.2 and carbon.

Methods of treating hydroconversion catalysts used for cracking of hydrocarbons are described. A method can include mixing an inactive hydroconversion catalyst with a solid hydrocarbon containing material having a melting point of 50° C. or greater. The inactive hydroconversion catalyst/solid hydrocarbon containing material mixture can be contacted with a gaseous stream that includes hydrogen (H.sub.2) and a sulfur-containing compound under conditions sufficient to sulfide the catalyst and carbonize at least a portion of the hydrocarbon containing material on the sulfided catalyst to obtain a treated sulfided hydroconversion catalyst.

Methods of treating hydroconversion catalysts used for cracking of hydrocarbons are described. A method can include mixing an inactive hydroconversion catalyst with a solid hydrocarbon containing material having a melting point of 50° C. or greater. The inactive hydroconversion catalyst/solid hydrocarbon containing material mixture can be contacted with a gaseous stream that includes hydrogen (H.sub.2) and a sulfur-containing compound under conditions sufficient to sulfide the catalyst and carbonize at least a portion of the hydrocarbon containing material on the sulfided catalyst to obtain a treated sulfided hydroconversion catalyst.

A method is disclosed for rejuvenation a cobalt Fischer Tropsch catalyst used in a Fischer Tropsch process operating in recycle mode. The method permits the use of specific inert gases to adjust the mole weight of the gas so that the recycle compressor designed for normal steady state operation can also be used in the method. Hydrogen from a membrane permeate stream is added to the reactor loop at a temperature between 300 F and 400 F and the carbon oxides are reacted out to purify the hydrogen. This stream is continuously recycled and the temperature is raised to between 425 F and 500 F and held at the final temperature for between 4 hours and 48 hours. The cobalt Fischer Tropsch catalyst is effectively rejuvenated in-situ by the method.

Provided are catalysts for reduction of nitrogen oxides including an active site including lanthanum vanadate represented by at least one of Formula 1 and Formula 2 and a support carrying the active site.
LaVO.sub.4 (wherein LaVO.sub.4 is polymorphous and has a tetragonal or monoclinic crystal structure)  Formula 1
LaV.sub.3O.sub.9 (wherein LaV.sub.3O.sub.9 has a monoclinic crystal structure)  Formula 2.

The invention relates to a method of regenerating the catalytic activity of a spent catalyst comprising nickel on a refractory oxide support, said method comprising the steps of contacting the spent catalyst with a nitric acid solution, heat-treating the spent catalyst, calcining and reducing the catalyst.

The presently disclosed embodiments relate to the utilization of coal-derived fine mineral matter in chemical recycling of plastics or of solid mixed plastic waste. The instantly disclosed mineral based catalyst benefits the processes of catalytic cracking, gasification and steam reforming to maximize carbon utilization and production of plastics of original quality from recycled or renewable feedstocks while reducing the plastic pollution in the environment. The catalyst can be based on inorganic fine mineral matter, a natural ancient mineral mixture found in coal deposits and containing a plurality of transition metals, such as iron, copper, and manganese, as well as calcium, barium, magnesium, potassium, sodium, which can act as co-catalysts. Addition of the catalyst can convert plastic to syngas at a faction of the energy of conventional technologies.

This disclosure relates to red mud compositions. This disclosure also relates to methods of making red mud compositions. This disclosure additionally relates to methods of using red mud compositions.

A dehydrogenation catalyst for producing olefins from alkane gases, in which cobalt and zinc are supported on alumina. A method for preparing the dehydrogenation catalyst for producing olefins from alkane gases, includes: preparing a mixed solution by mixing cobalt and zinc precursors with water; preparing a supported catalyst by impregnating alumina with the mixed solution; drying the supported catalyst; and calcining the dried supported catalyst at 500° C. to 900° C.