The present disclosure relates to a catalyst composition for the oligomerization of ethylene comprising a zirconium-containing catalyst and an organoaluminum-containing co-catalyst. The disclosure also relates to a process for oligomerization of ethylene in the presence of the catalyst composition according to the disclosure. The disclosed process results in C.sub.4-C.sub.20 linear alpha olefins having improved linearity.

Provided is a method of preparing an acrylonitrile dimer including: supplying an acrylonitrile monomer, a phosphorus-based catalyst, and an alcohol solvent to a reactor to perform a dimerization reaction to produce dimerized reactants (S10); cooling the dimerized reactants to crystallize the phosphorus-based catalyst (S20); separating the crystallized phosphorus-based catalyst (S30); and supplying the dimerized reactants from which the phosphorus-based catalyst is separated to a distillation column to separate the acrylonitrile dimer (S40).

Catalyst systems suitable for tetramerizing ethylene to form 1-octene may include a catalyst having a structure according to Formula (VI) or Formula (VII). In Formulas (VI) and (VII), X is a halogen, a (C.sub.2-C.sub.30) carboxylate, acetylacetonate, or a (C.sub.1-C.sub.30) hydrocarbyl; L.sub.1 is a neutral coordinating ligand; n is an integer from 0 to 6; Y is a (C.sub.6-C20)fluorine-substituted aryl, a (C.sub.6-C.sub.20)fluorine-substituted aryloxy, or a (C.sub.1-C.sub.20)fluorine-substituted alkoxy; and L∩L is a bidentate chelating ligand. The catalyst system may also include an aluminum containing agent which includes a reaction product of an organoaluminum compound and an antifouling compound. The antifouling compound may include one or more chlorinated hydrocarbons, chloro-aluminum alkyls, or combinations of these.

Catalyst systems suitable for tetramerizing ethylene to form 1-octene may include a catalyst having a structure according to Formula (VI) or Formula (VII). In Formulas (VI) and (VII), X is a halogen, a (C.sub.2-C.sub.30) carboxylate, acetylacetonate, or a (C.sub.1-C.sub.30) hydrocarbyl; L.sub.1 is a neutral coordinating ligand; n is an integer from 0 to 6; Y is a (C.sub.6-C.sub.20)fluorine-substituted aryl, a (C.sub.6-C.sub.20)fluorine-substituted aryloxy, or a (C.sub.1-C.sub.20)fluorine-substituted alkoxy; and L∩L is a bidentate chelating ligand. The catalyst system may also include an aluminum containing agent which includes a reaction product of an organoaluminum compound and an antifouling compound. The antifouling compound may include one or more polyether alcohols or one or more non-polymeric ethers.

Catalyst systems suitable for tetramerizing ethylene to form 1-octene may include a catalyst including a reaction product of a chromium compound and a ligand having the structure according to Formula (II). In Formula (II), A and C may be independently chosen from phosphorus, arsenic, antimony, bismuth, and nitrogen; B may be a linking group between A and C; and R.sub.1, R.sub.2, R.sub.3, and R.sub.4 may be independently chosen from a (C.sub.1-C.sub.50) hydrocarbyl or a (C.sub.1-C.sub.50) heterohydrocarbyl. The catalyst system may include a co-catalyst including a reaction product of an organoaluminum compound and an antifouling compound. The antifouling compound may include one or more quaternary salts; one or more organic acids, organic acid salts, esters, anhydrides, or combinations of these; one or more chlorinated hydrocarbons, chloro-aluminum alkyls, or combinations of these; one or more polyether alcohols; or one or more non-polymeric ethers.

A catalyst composition including: (a) a chromium compound; (b) a ligand of the general structure (A) R.sub.1R.sub.2P—N(R.sub.3)—P(R.sub.4)—NR.sub.5R.sub.6 or (B) R.sub.1R.sub.2P—N(R.sub.3)—P(XR.sub.7)R.sub.8 or R.sub.1R.sub.2P—N(R.sub.3)—P(XR.sub.7).sub.2, with X═O or S,
wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7 and R.sub.8 are independently C.sub.1-C.sub.10-alkyl, C.sub.6-C.sub.20-aryl, C.sub.3-C.sub.10-cycloalkyl, aralkyl, alkylaryl, or trialkylsilyl, or any cyclic derivatives of (A) and (B), wherein at least one of the P or N atoms of the PNPN-unit or PNP-unit is a member of the ring system, the ring system being formed from one or more constituent compounds of structures (A) or (B) by substitution; and (c) an activator or co-catalyst; and a process for tri- and/or tetramerization.

Catalyst compositions are prepared by contacting a palladium source and 1,3,5,7-tetramethyl-6-(2,4-dimethoxyphenyl)-2,4,8-trioxa-6-phosphaadamantane and a methoxyocta-diene compound, in a primary aliphatic alcohol, under suitable conditions including a ratio of equivalents of palladium to equivalents of 1,3,5,7-tetramethyl-6-(2,4-dimethoxyphenyl)-2,4,8-trioxa-6-phosphaadamantane ranging from greater than 1:1 to 1:1.3. The result is a complex of palladium, a 1,3,5,7-tetramethyl-6-(2,4-dimethoxyphenyl)-2,4,8-trioxa-6-phosphaada-mantane ligand, and a ligand selected from a methoxyoctadiene ligand, an octadienyl ligand, or a protonated octadienyl. Such complexes may, in solution, exhibit surprising solubility and storage stability and are useful in the telomerization of butadiene, which is a step in the production of 1-octene.

The disclosure provides a catalyst system and a method for ethylene oligomerization using this. The catalyst system contains: ligand a, containing carbene groups of imidazole ring type; transition metal compound b, that is one of IVB˜VIII group metal compounds; activator c, that is a compound containing III A group metals; the ligand a contains at least one group as shown in general formula I: ##STR00001##
in which, bridging group A contains a main chain including alkyl, alkenyl, aryl groups or the combination of them and the first heteratom; E is a linear or cyclic group containing the second heteroatom; R is a hydrocarbyl group. The catalyst system is especially used for trimerization and tetramerization of ethylene. The catalyst system has high selectivity for 1-hexene and 1-octene, low selectivity for 1-butene and 1-C.sub.10+, and the total percent content of C.sub.6˜C.sub.8 linear □α-olefin in the product is more than 90% by mass.

Catalyst systems suitable for tetramerizing ethylene to form 1-octene may include a catalyst including a chromium compound coordinated with a ligand and a co-catalyst including an organoaluminum compound. The ligand may have a chemical structure: (R.sub.1)(R.sub.2)A-X—C(R.sub.3)(R.sub.4). A and C may be phosphorus. X may be B(R.sub.5), Si(R.sub.5).sub.2, N(R.sub.5), wherein R.sub.5 is an aryl group substituted with a halogen, halogenated alkyl or a silyl group, and wherein B, or N, or Si is bound to A and C. R.sub.1, R.sub.2, R.sub.3, and R.sub.4 may be independently chosen hydrocarbyl groups or heterohydrocarbyl groups.

Metal-organic framework materials (MOFs) are highly porous entities comprising a multidentate organic ligand coordinated to multiple metal centers, typically as a coordination polymer. MOFs may comprise a plurality of metal centers, and a multidentate organic ligand coordinated via at least two binding sites to the plurality of metal centers to define an at least partially crystalline network structure having a plurality of internal pores, and in which the multidentate organic ligand comprises first and second binding sites bridged together with a third binding site comprising a diimine moiety. The multidentate organic ligand may comprise a reaction product of a vicinal dicarbonyl compound and an amine-substituted salicylic acid to define the first, second and third binding sites. Particular MOFs may comprise 5,59′-(((1E,2E)-ethane-1,2-diylidene)bis-(azaneylylidene))bis(2-hydroxybenzoic acid) as a multidentate organic ligand.