The present invention relates to a method for preparing, activating and regenerating a metal supported catalyst, comprising: treating a M.sub.a-M.sub.b-M.sub.c metal supported catalyst at 10-700? C. by using an ammonia or nitrogen-containing organic matter, wherein the M.sub.a metal is an active metal selected from one or more of a noble metal atom or a transition metal, the support is a common industrial porous catalyst, and the M.sub.a metal is dispersed on the support in a state of single atomic site. According to the M.sub.d-M.sub.b-M.sub.c metal supported noble metal/zinc catalyst treated by the method of the present invention, the direct dehydrogenation conversion rate and selectivity of catalyzing light alkanes are remarkably improved; the method for preparing the catalyst is simple in process, the catalytic activity after regeneration is still kept, and the catalyst can be industrially produced on a large scale.

The present invention relates to a method for preparing, activating and regenerating a metal supported catalyst, comprising: treating a M.sub.a-M.sub.b-M.sub.c metal supported catalyst at 10-700? C. by using an ammonia or nitrogen-containing organic matter, wherein the M.sub.a metal is an active metal selected from one or more of a noble metal atom or a transition metal, the support is a common industrial porous catalyst, and the M.sub.a metal is dispersed on the support in a state of single atomic site. According to the M.sub.d-M.sub.b-M.sub.c metal supported noble metal/zinc catalyst treated by the method of the present invention, the direct dehydrogenation conversion rate and selectivity of catalyzing light alkanes are remarkably improved; the method for preparing the catalyst is simple in process, the catalytic activity after regeneration is still kept, and the catalyst can be industrially produced on a large scale.

The invention provides a method of reducing the amount of nitrogen oxide components in a process gas stream comprising: a) contacting a deNO.sub.X catalyst with the process gas in the presence of ammonia which results in the conversion of nitrogen oxide components as well as a decline in the NO.sub.X conversion over the deNO.sub.X catalyst; and b) regenerating the deNO.sub.X catalyst to improve the NO.sub.X conversion by contacting the deNO.sub.X catalyst at a temperature in the range of from 250 to 390 C. with a flow of ammonia that is reduced relative to the flow of ammonia in step a) and process gas, air or a mixture thereof.

The invention provides a method of reducing the amount of nitrogen oxide components in a process gas stream comprising: a) contacting a deNO.sub.X catalyst with the process gas in the presence of ammonia which results in the conversion of nitrogen oxide components as well as a decline in the NO.sub.X conversion over the deNO.sub.X catalyst; and b) regenerating the deNO.sub.X catalyst to improve the NO.sub.X conversion by contacting the deNO.sub.X catalyst at a temperature in the range of from 250 to 390 C. with a flow of ammonia that is reduced relative to the flow of ammonia in step a) and process gas, air or a mixture thereof.

A hydroconversion catalyst obtained by the process described, comprising a mesoporized zeolite with healed zeolitic structure, containing at least one network of micropores and at least one network of mesopores, having an atomic Si/Al ratio within the zeolite framework of greater than or equal to 2.3 and showing reduced amount of extra-framework aluminium with regard to that of a mesoporized zeolite with no healed zeolitic structure.

A hydroconversion catalyst obtained by the process described, comprising a mesoporized zeolite with healed zeolitic structure, containing at least one network of micropores and at least one network of mesopores, having an atomic Si/Al ratio within the zeolite framework of greater than or equal to 2.3 and showing reduced amount of extra-framework aluminium with regard to that of a mesoporized zeolite with no healed zeolitic structure.

The invention relates to a process for preparing a catalyst comprising a mesoporized zeolite, comprising the steps of: preparation of a protonic mesoporized zeolite, which contains at least one network of micropores and at least one network of mesopores, and treatment in a gas or liquid phase containing ammonia or ammonium ions. The invention also related to the obtained catalyst and the use of this catalyst in hydroconversion processes.

The invention relates to a process for preparing a catalyst comprising a mesoporized zeolite, comprising the steps of: preparation of a protonic mesoporized zeolite, which contains at least one network of micropores and at least one network of mesopores, and treatment in a gas or liquid phase containing ammonia or ammonium ions. The invention also related to the obtained catalyst and the use of this catalyst in hydroconversion processes.

The present invention provides methods for low temperature desulfating sulfur-poisoned SCR catalysts, and emission control systems adapted to apply such desulfating methods, in order to regenerate catalytic NOx conversion activity. The methods are adapted for treating an SCR catalyst to desorb sulfur from the surface of the SCR catalyst and increase NOx conversion activity of the SCR catalyst, the treating step including treating the SCR catalyst with a gaseous stream comprising a reductant for a first treatment time period and at a first treatment temperature, wherein the first treatment temperature is about 350 C. or less, followed by a second treatment time period and a second treatment temperature higher than the first treatment temperature, wherein the molar ratio of reductant to NOx during the treating step is about 1.05:1 or higher.

The present invention provides methods for low temperature desulfating sulfur-poisoned SCR catalysts, and emission control systems adapted to apply such desulfating methods, in order to regenerate catalytic NOx conversion activity. The methods are adapted for treating an SCR catalyst to desorb sulfur from the surface of the SCR catalyst and increase NOx conversion activity of the SCR catalyst, the treating step including treating the SCR catalyst with a gaseous stream comprising a reductant for a first treatment time period and at a first treatment temperature, wherein the first treatment temperature is about 350 C. or less, followed by a second treatment time period and a second treatment temperature higher than the first treatment temperature, wherein the molar ratio of reductant to NOx during the treating step is about 1.05:1 or higher.