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 present invention relates to a catalyst system for olefin metathesis, the catalyst system comprising: a) a first system zone substantially comprising a layered double hydroxide; and b) a second system zone comprising a metathesis catalyst.

The present invention relates to a catalyst system for olefin metathesis, the catalyst system comprising: a) a first system zone substantially comprising a layered double hydroxide; and b) a second system zone comprising a metathesis catalyst.

This describes homogeneous catalysts that are recoverable from solution by being phase selective and through host-guest interactions. An example of a method includes separating a water soluble N-heterocyclic carbene homogeneous catalyst from a solution by: (a) forming a host-guest compound between the catalyst and an inclusion compound in the solution; and (b) isolating the host-guest compound from the solution.

This describes homogeneous catalysts that are recoverable from solution by being phase selective and through host-guest interactions. An example of a method includes separating a water soluble N-heterocyclic carbene homogeneous catalyst from a solution by: (a) forming a host-guest compound between the catalyst and an inclusion compound in the solution; and (b) isolating the host-guest compound from the solution.

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 an organic compound of formula (I)

##STR00001##

in which R1, R2, R3, R4 and R5 are selected from among a hydrogen atom, or a hydroxyl radical, or a hydrocarbon radical that comprises from 1 to 12 carbon atoms that can also comprise at least one oxygen atom, and R6 is selected from a hydrogen atom, a hydrocarbon radical that comprises from 1 to 12 carbon atoms that can also comprise at least one oxygen atom, a methacryloyl radical, an acryloyl radical or an acetyl radical. The invention also relates to the method for preparation of said catalyst and its use in a method for hydrotreatment and/or hydrocracking.

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 an organic compound of formula (I)

##STR00001##

in which R1, R2, R3, R4 and R5 are selected from among a hydrogen atom, or a hydroxyl radical, or a hydrocarbon radical that comprises from 1 to 12 carbon atoms that can also comprise at least one oxygen atom, and R6 is selected from a hydrogen atom, a hydrocarbon radical that comprises from 1 to 12 carbon atoms that can also comprise at least one oxygen atom, a methacryloyl radical, an acryloyl radical or an acetyl radical. The invention also relates to the method for preparation of said catalyst and its use in a method for hydrotreatment and/or hydrocracking.

Residual hydrogenation catalyst produced from reduction of nitrile rubber is recovered by a chelation step using a chelating agent and a series of extraction using semi-coagulation with polar solvents and an optional washing steps for the separation of catalyst-chelating agent complex from hydrogenated nitrile rubber solution. The chelating agent is selected from xanthate, dithiocarbamate, and trithiocarbonate compounds.

Residual hydrogenation catalyst produced from reduction of nitrile rubber is recovered by a chelation step using a chelating agent and a series of extraction using semi-coagulation with polar solvents and an optional washing steps for the separation of catalyst-chelating agent complex from hydrogenated nitrile rubber solution. The chelating agent is selected from xanthate, dithiocarbamate, and trithiocarbonate compounds.