The present disclosure relates to a method for regenerating a waste organic zinc catalyst by performing surface modification using a dicarboxylic acid and a zinc compound. When using the method for regenerating an organic zinc catalyst according to the present disclosure, the organic zinc catalyst can be regenerated using a convenient method which modifies the dicarboxylic acid and the zinc compound in an alternately repeated manner.

A method for separating a homogeneous catalyst from a solution includes forming a host-guest compound between a first isomer of the catalyst and inclusion compound in the solution and isolating the host-guest compound from the solution. The catalyst may be released from the inclusion compound by converting the first isomer of the catalyst to a second isomer of the catalyst.

A method for separating a homogeneous catalyst from a solution includes forming a host-guest compound between a first isomer of the catalyst and inclusion compound in the solution and isolating the host-guest compound from the solution. The catalyst may be released from the inclusion compound by converting the first isomer of the catalyst to a second isomer of the catalyst.

The invention belongs to the field of nitrogen oxide control in environmental protection science and technology, and particularly relates to the field of regeneration and utilization of SCR denitration catalyst with calcium poisoning, that is a neutral complex cleaning liquid and a regeneration method for denitration catalyst with calcium poisoning. The present invention uses a neutral polyether surfactant as a regeneration and calcium removal reagent to achieve a poisoned catalyst regeneration method with high calcium removal rate, low loss rate of active components and excellent recovery of denitrification activity; wherein the content of the polyether surfactant is in the range of 0.1-1 wt %; by the regeneration method of the present invention, the loading of active components which is required in the conventional regeneration process can be omitted, while the corrosion of equipment and catalyst can be reduced, thus capable of regenerating the denitration catalyst with high efficiency.

The invention belongs to the field of nitrogen oxide control in environmental protection science and technology, and particularly relates to the field of regeneration and utilization of SCR denitration catalyst with calcium poisoning, that is a neutral complex cleaning liquid and a regeneration method for denitration catalyst with calcium poisoning. The present invention uses a neutral polyether surfactant as a regeneration and calcium removal reagent to achieve a poisoned catalyst regeneration method with high calcium removal rate, low loss rate of active components and excellent recovery of denitrification activity; wherein the content of the polyether surfactant is in the range of 0.1-1 wt %; by the regeneration method of the present invention, the loading of active components which is required in the conventional regeneration process can be omitted, while the corrosion of equipment and catalyst can be reduced, thus capable of regenerating the denitration catalyst with high efficiency.

A chemical reaction is catalyzed in an organic solvent using a water soluble N-heterocyclic carbene homogeneous catalyst to form a reaction mixture. An aqueous phase in the reaction mixture. A solvent in which the catalyst is insoluble is added to the reaction mixture, causing the catalyst to migrate to the aqueous phase to form a catalyst-laden aqueous phase. The catalyst is extracted from the catalyst-laden aqueous phase.

A chemical reaction is catalyzed in an organic solvent using a water soluble N-heterocyclic carbene homogeneous catalyst to form a reaction mixture. An aqueous phase in the reaction mixture. A solvent in which the catalyst is insoluble is added to the reaction mixture, causing the catalyst to migrate to the aqueous phase to form a catalyst-laden aqueous phase. The catalyst is extracted from the catalyst-laden aqueous phase.

The invention has as its object a catalyst that comprises a substrate based on alumina or silica or silica-alumina, at least one element from group VIII, at least one element from group VIB, and at least one additive that is selected from among 2-acetylbutyrolactone and/or its hydrolysis products, 2-(2-hydroxyethyl)-3-oxobutanoic acid, and 3-hydroxy-2-(2-hydroxyethyl)-2-butenoic acid. The invention also relates to the method for preparation of said catalyst and its use in a method for hydrotreatment and/or hydrocracking.

A process for rejuvenating an at least partially spent catalyst resulting from a hydrodesulfurization process of a sulfur-containing olefinic gasoline cut, where the at least partially spent catalyst result is from a fresh catalyst a metal from group VIII, a metal from group VIb, and an oxide support, where the process includes a) regenerating the at least partially spent catalyst in an oxygen-containing gas stream at a temperature between 350? C. and 550? C., b) the regenerated catalyst is brought into contact with an impregnation solution containing a compound containing a metal from group VIb, the molar ratio of the metal from group VIb added per metal from group VIb already present in the regenerated catalyst being between 0.15 and 2.5 mol/mol, c) a drying stage is carried out at a temperature of less than 200? C., and the use of the rejuvenated catalyst in a hydrodesulfurization process.

A process for rejuvenating an at least partially spent catalyst resulting from a hydrodesulfurization process of a sulfur-containing olefinic gasoline cut, where the at least partially spent catalyst result is from a fresh catalyst a metal from group VIII, a metal from group VIb, and an oxide support, where the process includes a) regenerating the at least partially spent catalyst in an oxygen-containing gas stream at a temperature between 350? C. and 550? C., b) the regenerated catalyst is brought into contact with an impregnation solution containing a compound containing a metal from group VIb, the molar ratio of the metal from group VIb added per metal from group VIb already present in the regenerated catalyst being between 0.15 and 2.5 mol/mol, c) a drying stage is carried out at a temperature of less than 200? C., and the use of the rejuvenated catalyst in a hydrodesulfurization process.