Abstract: A method of deactivate a catalyst system is described. The method may include contacting a reactor effluent comprising a catalyst system, an oligomerized olefin, and diluent with a kill agent to at least partially deactivate the catalyst system, separating the reactor effluent into one or more first streams comprising oligomerized olefin and diluent, the one or more first streams being substantially devoid of the at least partially deactivated catalyst, and a second stream comprising the deactivated catalyst; and contacting the second stream with a quench agent.

Abstract: The present invention relates to an in-line method for generating comonomer, from monomer, such as ethylene. The comonomer generated is stored prior to transporting to a polyethylene polymerization reactor. The in-line method includes the steps of providing an in-line comonomer synthesis reactor and a downstream gas/liquid phase separator prior to the polymerization reactor; feeding ethylene monomer and a catalyst in a solvent and/or diluent to the comonomer synthesis reactor; reacting the ethylene monomer and the catalyst in solvent and/or diluent under reaction conditions to produce an effluent stream including ethylene monomer and comonomer; passing the effluent stream from the comonomer synthesis reactor to the downstream gas/liquid phase separator to separate a gas stream from a bottom stream, wherein the gas stream is a mixture of ethylene monomer and comonomer; and passing the gas stream to the polymerization reactor to provide the necessary comonomer input.

Abstract: This invention relates to processes to produce liquid poly-alpha-olefins (PAOs) having a kinematic viscosity at 100° C. of more than 20 cSt in the presence of a metallocene catalyst with a non-coordinating anion activator and hydrogen.

Abstract: The invention provides transition metal complex compounds, high-activity olefin oligomerization catalysts containing the compounds, and olefin oligomerization processes using the catalysts. A transition metal complex compound [A] according to the invention is represented by Formula (I) or Formula (I?) below. An olefin oligomerization catalyst includes the transition metal complex compound [A]. In an olefin oligomerization process of the invention, an olefin is oligomerized in the presence of the catalyst.

Abstract: A process for dimerizing alpha olefins comprising contacting (i) an alpha olefin having at least 3 carbon atoms, (ii) a hexadentate bimetallic catalyst, and (iii) a cocatalyst, and dimerizing the alpha olefin in a reaction zone at conditions effective to dimerize an alpha olefin to form a reaction zone effluent comprising alpha olefin oligomers including alpha olefin dimers. A process for dimerizing olefins comprising contacting (i) an alpha olefin having at least 3 carbon atoms, (ii) a hexadentate bimetallic complex comprising a cobalt compound, and (iii) a cocatalyst, and dimerizing the alpha olefin in a reaction zone at conditions effective to dimerize an alpha olefin to form a reaction zone effluent comprising oligomers including dimmers, wherein greater than 20 weight percent of the alpha olefin has been converted to oligomers, greater than 30 weight percent of the oligomers are dimers, and greater than 85 mole percent of the dimers are linear.

Abstract: The present invention relates to a method and a reactor system, for the oligomerization of ethylene, comprising oligomerizing ethylene in a reactor in the presence of a solvent and a catalyst composition to produce a liquid product stream comprising linear alpha-olefins, solvent and catalyst composition, and deactivating and extracting the catalyst composition in said liquid product stream by mixing it with a polar phase in a dynamic mixing device having rotor and stator elements comprising concentric tool rings.

Abstract: The invention is directed to polyalphaolefins (PAOs) and processes for forming PAOs. In one embodiment, the invention is to a process for forming a PAO comprising polymerizing C8-C12 ?-olefin monomers in the presence of hydrogen, a C8-C12 saturated hydrocarbon, e.g., a C8-C12 saturated straight-chain hydrocarbon, and a catalyst system in a reaction vessel, wherein the C8-C12 saturated straight-chain hydrocarbon has about the same number of carbon atoms as the C8-C12 ?-olefin monomers. The C8-C12 saturated straight-chain hydrocarbon optionally is derived from a crude PAO product formed by the process of the invention. The invention is also directed to reaction systems for performing the processes of the invention, to processes for controlling PAO viscosity based on residence time, and to the removal of spent catalyst using a solid adsorbent particles.

Abstract: The present invention relates to a method for preparing linear alpha olefin comonomers, such as 1-butene, 1-hexene or 1-octene, from ethylene monomer. The comonomer generated is stored on site for use in a subsequent process, such as a polyethylene polymerization reactor. The method includes the steps of feeding an ethylene monomer, and a catalyst in a solvent to one or more comonomer synthesis reactors; reacting the ethylene monomer and the catalyst in solvent under reaction conditions to produce an effluent stream comprising unreacted ethylene monomer, a catalyst in a solvent, and comonomer; passing the effluent stream to one or more downstream gas/liquid phase separators to form a gas stream of unreacted ethylene monomer, and a liquid stream of comonomer, and catalyst in a solvent; recycling to the one or more comonomer synthesis reactors the unreacted ethylene monomer and a portion of the liquid stream; and storing a remaining portion of said liquid stream for subsequent processing of the comonomer.

Abstract: This disclosure provides for alpha olefin oligomers and polyalphaolefins (or PAOs) and methods of making the alpha olefin oligomers and PAOs. This disclosure encompasses metallocene-based alpha olefin oligomerization catalyst systems, including those that include at least one metallocene and an activator comprising a solid oxide chemically-treated with an electron withdrawing anion. The alpha olefin oligomers and PAOs prepared with these catalyst systems can have a high viscosity index combined with a low pour point, making them particularly useful in lubricant compositions and as viscosity modifiers.

Abstract: According to the present invention there is provided a process for producing an oligomeric product by the oligomerisation of at least one olefinic compound including: A) providing an activated oligomerisation catalyst comprising the combination of: i) a source of a transition metal; ii) a ligating compound of the formula (R1)mX1(Y)X2(R2)n iii) a metal containing activator; and (iv) at least one olefinic compound; B) diluting the activated oligomerisation catalyst of A with an introduced liquid medium; and C) contacting the at least one olefinic compound to be oligomerised with the diluted activated catalyst of B to produce an oligomeric product.

Abstract: The present invention relates to a method for the preparation of linear alpha-olefins by oligomerization of ethylene in a reactor in the presence of a catalyst and solvent, wherein an outlet stream from the reactor comprising the solvent, catalyst and linear alpha-olefins is heated by at least one heating means to a temperature at which all or substantially all of the linear alpha-olefins are dissolved and/or melted in the outlet stream; and a reactor system therefor.

Abstract: A process is provided to stabilize and/or reactivate an olefin production catalyst system which comprises contacting an olefin production catalyst system, either before or after use, with an aromatic compound.

Abstract: The present invention relates to a process for the preparation of linear low molecular weight alpha-olefins having 4 to 24 carbon atoms, comprising oligomerizing ethylene in an inert solvent in the presence of a catalyst system comprising: (i) zirconium carboxylate of the formula (R1COO)mZrCl4-m, wherein R1 is saturated or unsaturated aliphatic C1-C10 hydrocarbon or aromatic C6-C14 hydrocarbon and m fulfills 1?m?4, (ii) at least one aluminum compound selected from organoaluminum compounds of the formula R2nAlX3-n, wherein R2 is C1-C20 alkyl, X is chlorine, bromine or iodine, and n fulfills 1?n?2, and/or aluminoxanes, and (iii) at least two different additives selected from the group consisting of hydrogen, esters, ketones, ethers, amines, anhydrides, phosphines and sulfur compounds; as well as to a catalyst used therein.

Abstract: A process for producing an olefin oligomer, which comprises the steps of (1) contacting a transition metal compound with a compound represented by the formula, R1R2A—G—AR3R4, to produce a contact product (i), (2) contacting an alumoxane compound with an organoaluminum compound to produce a contact product (ii), and (3) contacting the contact product (i), the contact product (ii), and an olefin with one another, wherein A is a nitrogen atom, a phosphorus atom, an arsenic atom or an antimony atom; G is a divalent group; and R1, R2, R3 and R4 are independently of one another a hydrocarbyl group, a halogenated hydrocarbyl group, an oxygen-containing hydrocarbyl group, a sulfur-containing hydrocarbyl group, a selenium-containing hydrocarbyl group, or a tellurium-containing hydrocarbyl group.

Abstract: The present invention relates to a process for the gas-phase (co-)polymerisation of olefins in a fluidised bed reactor using a Ziegler-Natta type catalyst characterised in that the polymerisation is performed in the presence of a monohalogenated hydrocarbon compound.

Abstract: This invention relates to the field of olefin polymerization catalyst compositions, and methods for the polymerization and copolymerization of olefins, typically using a supported catalyst composition. In one aspect, this invention encompasses precontacting a metallocene with a borinic acid or boronic acid prior to contacting this mixture with the acidic activator-support and an organoaluminum compound.

Abstract: A process for preparing ?-olefins from ethylene wherein the ?-olefins are substantially free of olefins having greater than 12 carbon atoms comprises contacting ethylene under oligomerization conditions with a 2,6-bis(phenylimino) pyridyl metal halide catalyst in which the metal is Fe, Ni, Co or Pd.

Abstract: A process for producing an olefin oligomer, which comprises the steps of (1) contacting an olefin with an organoaluminum compound to produce a contact product (i), (2) contacting a transition metal compound with a compound represented by the formula, R1R2A-G-AR3R4, to produce a contact product (ii), and (3) contacting the contact product (i), the contact product (ii), an alumoxane compound, and optionally an olefin with one another, wherein A is a nitrogen atom, a phosphorus atom, an arsenic atom or an antimony atom, and As are the same as or different from each other; G is a divalent group; and R1, R2, R3 and R4 are independently of one another a hydrocarbyl group, a halogenated hydrocarbyl group, an oxygen-containing hydrocarbyl group, a sulfur-containing hydrocarbyl group, a selenium-containing hydrocarbyl group, or a tellurium-containing hydrocarbyl group.

Abstract: The present invention relates to a process for the production of highly reactive polyisobutenes with a content of terminal vinylidene groupings of greater than 80 mol % and an average molecular weight of 500 to 10,000 Dalton by cationic polymerization of isobutene or of isobutene and monomers copolymerizable with isobutene in the presence of solvent-stabilized transition metal complexes with weakly coordinated anions.

Abstract: The use of a phosphorus containing Ligand as a Ligand for a metathesis catalyst in a catalysed metathesis reaction wherein the phosphorus containing Ligand is a heterocyclic organic compound with a ligating phosphorus atom as an atom in the heterocyclic ring structure of the heterocyclic organic compound. The invention also relates to a metathesis catalyst such a phosphorus containing Ligand and to a metathesis reaction using the catalyst.

Abstract: Olefins are oligomerized by contacting an olefin with a catalyst system that is comprised of a) at least one transition metal complex that is complexed with a polydentate complexing ligand and b) an alkylaluminoxane, each component being present in such amounts that the molar ratio of aluminum transition metal is greater than 10, wherein at least part of the amount of the transition metal complex is added continuously or in portions during the oligomerization.

Abstract: A catalyst for the oligomerization of olefins, especially ethylene contains: at least one nickel complex e.g. Li2 Ni X2 that results from bringing into contact a nickel salt e.g. a nickel carboxylate with a bidentate chelating ligand containing a nitrogen-containing heterocyclic compound with an alcohol e.g. Ha-C(OH)RR?; and at least one hydrocarbylaluminum compound from tris(hydrocarbyl)aluminum compounds, chlorinated or brominated hydrocarbylaluminum compounds or at least one aluminoxane.

Abstract: A process is described for obtaining from an “FCC” initial C5 fraction which is enriched with isoprene and purified and usable for the selective polymerization of isoprene. A process is also described for obtaining an isoprene homopolymer from a polymerization medium comprising isoprene and at least one methyl butene, such as said “FCC” C5 fraction which is enriched with isoprene and purified. The process of obtaining the final fraction from the initial C5 fraction includes: a catalytic hydrogenation reaction of said initial C5 fraction by a palladium-based catalyst, which produces an intermediate C5 fraction comprising n-pentenes in a mass ratio which is less than 0.

Abstract: A process is provided to stabilize and/or reactivate an olefin production catalyst system which comprises contacting an olefin production catalyst system, either before or after use, with an aromatic compound.

Abstract: Disclosed is a method for the oligomerization of olefins, wherein an olefin is brought into contact with a catalyst system that is obtained from a chromium source, a cycloalkylalkyl-substituted triazacyclohexane, especially a 1,3,5-tris-(cycloalkylalkyl)-1,3,5-triazacyclohexane and an activator such as an alkyl aluminum compound or an alkylalumoxane.

Abstract: ?-Olefins are made in a modified plug flow reactor system by the oligomerization of ethylene using an iron complex of a selected diimine of a 2,6-pyridinecarboxaldehyde(bisimine) or 2,6-diacylpyridine(bisimine) as the oligomerization catalyst. The reactor is modified to add the iron complex at two or more points along the length of the plug flow reactor, the distance between addition points being dependent on the half-life of the active ethylene oligomerization catalyst.

Abstract: This invention relates generally to synthetic procedures that include the step of ring-opening metathesis of cyclic olefins and reaction with an acyclic diene co-reactant to produce regularly repeating A,B-alternating olefin polymers. The A,B-alternating polymers are produced by varying reaction conditions and/or reactant proportions and using only two types of olefin metathesis (ring-opening and cross) to provide regularly repeating ABAB . . . etc. polymers via ring-opening metathesis polymerization (ROMP). More particularly, the invention pertains to synthesis of A,B-alternating olefin polymers via olefin metathesis reactions using a Group 8 transition metal complex as the metathesis catalyst. Polymers provided herein have utility in a variety of fields, including not only polymer chemistry per se, but also in the pharmaceutical, biomedical, and packaging industries where the structure and properties of polymers need to be tightly controlled.

Abstract: A process for the preparation of low molecular weight linear alpha olefins is disclosed. The process comprises oligomerising ethylene in an inert aliphatic or aromatic solvent in the presence of a catalyst comprising of a first component selected from zirconium alkoxide and zirconium aryloxide and a second component selected from alkyl aluminum halide and/or alkyl aluminum.

Abstract: A liquid polyalphaolefin homo- or copolymer, preferably 1-decene, which is substantially amorphous is obtained by a polymerization process employing hydrogen and a particular type of metallocene catalyst. Additionally, liquid polyalphaolefin homo- or copolymer containing from 2 to about 12 carbon atoms possess a unique combination of properties, i.e., low molecular weight (Mw), low polydispersity index (Mw/Mn controllable kinematic viscosity (Kv100), low Iodine Number (I2) and low glass transition temperature (Tg) and are substantially amorphous. The liquid polyalphaolefin homo- or copolymers provided herein are useful for manufacturing a variety of products including lubricating oils in which the polyalphaolefin functions as a viscosity modifier.

Abstract: The present invention is related to a method for oligomerizing olefinic monomers under oligomerization conditions to form higher olefins. The novel method comprises contacting a feed comprising the olefinic monomers with a catalyst composition comprising the reaction product of: (a) a compound having a formula selected from the group consisting of M[S2C2(RaRb)]2 and M[S2C6(R1R2R3R4)]2, wherein M is a late transition metal, Ra, Rb, R1, R2, R3 and R4 are independently selected and may be the same or different and are selected from hydrogen, electron-withdrawing groups and unsubstituted and substituted hydrocarbyl groups; and (b) an activating cocatalyst. The improved method advantageously relates to oligomerizing olefinic monomers from feed streams having contaminants, especially sulfur-containing contaminants.

Abstract: The invention is a method and catalyst for selectively and efficiently producing short chain linear &agr;-olefins. The method includes contacting olefinic monomers under oligomerization conditions with the catalyst composition which comprises a composition prepared in situ by reacting a nickel compound selected from the group consisting of halides, hydrides, triflates, acetates, borates, C1, through C12 alkyl, C1 through C12 alkoxy, C3 through C12 cycloalkyl, C3 through C12 cycloalkoxy, aryl, thiolates, carbon monoxide, cyanate, olefins including diolefins and cycloolefins, and any other moiety into which a monomer can insert and mixtures thereof, with an amine ligand wherein said ligand is a nitrogen-containing ligand having one or more nitrogen atoms.

Abstract: A process for the production of an oligomer oil by the polymerization of a feedstock containing one or more C3 to C20 1-olefins in the presence of a solid unsupported metallocene- and activator-containing catalyst system which is formed by removing the solvent from a solution of the soluble metallocene- and activator-containing catalyst system.

Abstract: The invention pertains to a process of removing phosphorous-containing impurities and preferably also dienes, from an olefin stream using a sorbent selected from the group consisting of an acidic ion exchange resin, an acidic zeolite, an acidic alumina, a neutral alumina, and an activated carbon. The olefin stream preferably comprises primarily olefins having at least 6 carbon atoms.

Abstract: A process is described for carrying out olefin oligomerisation in two catalysis steps of different types, using an organic feed containing at least one olefin. The cut to be treated, containing at least one olefin (Cn), is introduced into a first reaction zone where, in a first step, it undergoes catalytic oligomerisation either of the homogeneous liquid phase type, or of the heterogeneous type with a solid support. The effluent produced is generally sent to a heat exchanger traversed by a cold liquid, the effluent thus being cooled before being sent to a second reaction zone where it undergoes catalytic oligomerisation in a liquid—liquid two-phase medium, the invention being characterized in that at least an ethylenic hydrocarbon containing 3 to 5 carbon atoms per molecule is added to the inlet to the second reaction zone.

Abstract: A process for producing a linear &agr;-olefin which comprises: reacting a stoichiometric excess of a terminal Cn olefin with ethylene in the presence of an organometallic catalyst to produce a Cn+2 linear &agr;-olefin, wherein the catalyst is capable of producing a Schulz-Flory distribution of the linear &agr;-olefin with a Schulz-Flory constant of less than about 0.8 and wherein n is an integer between about 3 to 20.

Abstract: A catalytic composition for oligomerizing ethylene, in particular to 1-hexene, is obtained by mixing at least one chromium carboxylate characterized in that it also contains a free carboxylic acid in a set proportion, with at least one aryloxy compound of an element M selected from the group formed by magnesium, calcium, strontium and barium, with general formula M(RO)2-nXn in which RO is an aryloxy radical containing 6 to 80 carbon atoms, X is a halogen atom or a hydrocarbyl radical containing 1 to 30 carbon atoms and n is a whole number that can take the values 0 or 1, and with at least one hydrocarbylaluminum compound selected from the group formed by tris(hydrocarbyl)-aluminum compounds, chlorinated or brominated hydrocarbylaluminum compounds and aluminoxanes.

Abstract: There is disclosed a process for producing an ethylenic oligomer which comprises subjecting ethylene to oligomerization reaction in an organic solvent in the presence of a Ziegler based catalyst, and recyclingly using for the oligomerization reaction, the organic solvent separated by distilling the resultant oligomerization reaction product, wherein the water concentration in the oligomerization reaction system is at most 8 ppm by weight, or the concentration of olefins which have at least 3 carbon atoms and which are contained in the organic solvent to be recycled in the oligomerization reaction system is at most 2% by weight. The process of the present invention can maintain the catalytic activity of the catalyst at a high level.

Abstract: The present invention is related to a method for oligomerizing olefinic monomers under oligomerization conditions to form higher olefins. The novel method comprises contacting a feed comprising the olefinic monomers with a catalyst composition comprising the reaction product of: (a) a compound having a formula selected from the group consisting of M[S2C2(RaRb)]2 and M[S2C6(R1R2R3R4)]2, wherein M is a late transition metal, Ra, Rb, R1, R2, R3 and R4 are independently selected and may be the same or different and are selected from hydrogen, electron-withdrawing groups and unsubstituted and substituted hydrocarbyl groups; and (b) an activating cocatalyst. The improved method advantageously relates to oligomerizing olefinic monomers from feed streams having contaminants, especially sulfur-containing contaminants.

Abstract: A multistep process for the selective production of an oligomer oil having predetermined properties in which the first step involves the polymerization of a feedstock containing one or more C3 to C20 1-olefins in the presence of a catalyst comprising a bulky ligand transition metal catalyst and in which a subsequent step involves the olgiomerization of at least a preselected fraction of the product of the first step.

Abstract: A multistep process for the selective production of an oligomer oil having predetermined properties in which the first step involves the polymerization of a feedstock containing one or more C3 to C20 1-olefins in the presence of a catalyst comprising a bulky ligand transition metal catalyst and in which a subsequent step involves the olgiomerization of at least a preselected fraction of the product of the first step.

Abstract: This invention relates to a method to oligomerize ethylene comprising combining ethylene with a catalyst system comprising an activator and one or more phenoxide group metal compounds represented by the formula: wherein R3, R4, R5, R8, R9 and R10 may each independently be hydrogen, a halogen, a heteroatom containing group or a C1 to C100 group, provided that at least one of these groups has a Hammett &sgr;p value (Hansch, et al Chem. Rev. 1991, 91, 165) greater than 0.20; R2 and R7 may each independently be alkyl, aryl or silyl groups; R1 and R6 may each independently be an alkyl group, an aryl group, an alkoxy group, or an amino group; N is nitrogen; H is hydrogen; O is oxygen; M is a group 4 transition metal; and each X may each independently be an anionic ligand or a dianionic ligand.

Abstract: Ethylene and/or propylene are polymerized to form highly branched, liquid polymers by contacting ethylene and/or propylene monomer, in the presence of an inert reaction medium, with a catalyst system which comprises (1) an alkyl aluminum component, (2) an aluminum or gallium trihalide component, and, optionally, (3) a Group 4 metallocene dihalide component.

Abstract: The invention provides a hydrocarbon conversion process for converting olefins to longer chain hydrocarbons, the process using a catalyst system including a non-nickel transition metal derived catalyst and one or more ionic liquids at a reaction temperature of between 10° C. and 130° C. and a reaction pressure of up to 100 Bar. The hydrocarbon conversion process may be oligomerisation and trimerisation.

Abstract: A process for the production of dimers from an olefinic feedstock containing &agr;-olefins, by contacting the feedstock with a metallocene/aluminoxane catalyst, thereby selectively to dimerize &agr;-olefins in the feedstock by way of a metallocene-catalyzed dimerization reaction. The feedstock is in the form of a Fischer-Tropsch-derived definic feedstock involving a mixture of Fischer-Tropsch-derived hydrocarbons made up of at most 90% by mass of &agr;-olefins, at least 5% by mass of olefins, other than &agr;-olefins, selected from linear internal olefins, branched internal olefins, cyclic olefins, dienes, trienes and mixtures thereof, at least 5% by mass of constituents, other than olefins, selected from paraffins, oxygenated hydrocarbons, aromatic hydrocarbons and mixtures thereof. The metallocene-catalyzed dimerization reaction takes place while the olefins which are dimerized form part of the mixture constituted by the feedstock.

Abstract: A process for the preparation of low molecular weight linear alpha olefins is disclosed. The process comprises oligomerising ethylene in an inert aliphatic or aromatic solvent in the presence of a catalyst comprising of a first component selected from zirconium alkoxide and zirconium aryloxide and a second component selected from alkyl aluminum halide and/or alkyl aluminum.

Abstract: The present invention intends to provide an ethylene/&agr;-olefin copolymer of specific structure, exhibiting excellent performance as a lubricant oil additive, capable of having various functional groups in high ratio, and serviceable as raw material for various solubilizing agents. The ethylene/&agr;-olefin copolymer of the present invention is composed of ethylene and an &agr;-olefin having 3 to 10 carbon atoms, and characterized by specific characteristics.

Abstract: A process for oligomerising olefins in an organic feed containing at least one olefin comprises two steps with different types of catalysis. The cut to be treated containing at least one olefin (Cn) is introduced via line 1 into a reaction zone R1 where in a first step it undergoes catalytic oligomerisation, either of a liquid phase homogeneous type, or heterogeneous with a solid support. The effluent produced is sent via line 2 to a heat exchanger E1 traversed by a cold liquid. The effluent is thus cooled before being sent via line 3 to a second reaction zone R2 where it undergoes catalytic oligomerisation in a liquid-liquid two-phase medium. After reaction, the effluent is fed via line 4 to a zone L1 where it is washed. After washing, the hydrocarbon fraction is sent via line 5 to separator S1.

Abstract: A method for the cross-metathesis of terminal olefins is disclosed. The method describes making disubstituted internal olefin products by contacting a first terminal olefin with another first terminal olefin to form a dimer and then contacting the dimer with a second terminal olefin in the presence of a catalyst having the formula where M may be Os or Ru, R and R1 may be the same or different and may be hydrogen or a substitutent group selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20alkynyl, aryl, C1C20 carboxylate, C1-C20 alkoxy, C2-C20 alkenyloxy, C2-C20 alkynyloxy, aryloxy, C2-C20 alkoxycarbonyl, C1-C20 alkylthio, C1-C20 alkylsulfonyl, and C1-C20 alkylsulfinyl. X and X1 may be the same or different and may be any anionic ligand. L and L1 may be the same or different and may be any neutral electron donor.

Abstract: The invention is a method and catalyst for selectively and efficiently producing short chain linear &agr;-olefins. The method includes contacting olefinic monomers under oligomerization conditions with the catalyst composition which comprises a composition prepared in situ by reacting a nickel compound selected from the group consisting of halides, hydrides, triflates, acetates, borates, C1, through C12 alkyl, C1 through C12 alkoxy, C3 through C12 cycloalkyl, C3 through C12 cycloalkoxy, aryl, thiolates, carbon monoxide, cyanate, olefins including diolefins and cycloolefins, and any other moiety into which a monomer can insert and mixtures thereof, with an amine ligand wherein said ligand is a nitrogen-containing ligand having one or more nitrogen atoms.

Abstract: The present invention relates to a process for dimerizing lower olefins characterized by the use of a catalyst comprising the following three components: (1) at least one salt or complex of a transition metal belonging to the platinum group of the periodic table, (2) at least one organoaluminum compound and (3) at least one inorganic metallic compound.