The present disclosure relates to a catalyst system comprising i) (a) an N.sup.2-phosphinyl bicyclic amidine chromium salt or (b) a chromium salt and an N.sup.2-phosphinyl bicyclic amidine and ii) an organoaluminum compound. The present disclosure also relate to a process comprising: a) contacting i) ethylene; ii) a catalyst system comprising (a) an N.sup.2-phosphinyl bicyclic amidine chromium salt complex or (b) a chromium salt and an N.sup.2-phosphinyl bicyclic amidine; ii) an organoaluminum compound, and iii) optionally an organic reaction medium; and b) forming an oligomer product in a reaction zone.

The present disclosure relates to a catalyst system comprising i) (a) a bicyclic 2-[(phosphinyl)aminyl] cyclic imine chromium salt or (b) a chromium salt and a bicyclic 2-[(phosphinyl)aminyl] cyclic imine and ii) an organoaluminum compound. The present disclosure also relates to a process comprising: a) contacting i) ethylene; ii) a catalyst system comprising (a) a 2-[(phosphinyl)aminyl] cyclic imine chromium salt complex or (b) a chromium salt and a bicyclic 2-[(phosphinyl)aminyl] cyclic imine; ii) an organoaluminum compound, and iii) optionally an organic reaction medium; and b) forming an oligomer product in a reaction zone.

Catalyst systems for tetramerizing ethylene to form 1-octene may include a catalyst which may include a chromium compound coordinated with a ligand and a co-catalyst which may include an organoaluminum compound. The ligand may have a chemical structure according to Chemical Structure (I), wherein R.sub.5 is a (C.sub.1-C.sub.15) alkyl group, a (C.sub.3-C.sub.15) cyclohydrocarbyl group, a (C.sub.3-C.sub.15) cycloheterohydrocarbyl group, or a (C.sub.1-C.sub.15) aryl group, and R.sub.A, R.sub.B, R.sub.C, R.sub.D, R.sub.E, R.sub.F, R.sub.G, R.sub.H, R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.6, R.sub.7, R.sub.8, and R.sub.9 are independently chosen from a hydrogen atom, a (C.sub.1-C.sub.50) hydrocarbyl group, or a (C.sub.1-C.sub.50) heterohydrocarbyl group.

Methods of preparing oligomers of an olefin are provided. The methods can include providing an alkylaluminum compound and irradiating the alkylaluminum compound with microwave radiation to provide an irradiated alkylaluminum compound. The methods can further include mixing the irradiated alkylaluminum compound with a chromium compound, a pyrrole compound, and a zinc compound to provide a catalyst composition. The methods can further include contacting an olefin with the composition to form oligomers of the olefin. The olefin can include ethylene, and the oligomers of the olefin can include 1-hexene.

The present disclosure relates to a ligand compound, a catalyst system for oligomerization, and a method for olefin oligomerization using the same. The catalyst system for oligomerization using the ligand compound according to the present disclosure has excellent catalytic activity, exhibits high selectivity to 1-hexene and 1-octene, and greatly reduces the production of the by-products, thereby enabling efficient preparation of alpha-olefin.

The present disclosure relates to a catalyst system comprising i) (a) an N.sup.2-phosphinyl bicyclic amidine chromium salt or (b) a chromium salt and an N.sup.2-phosphinyl bicyclic amidine and ii) an organoaluminum compound. The present disclosure also relate to a process comprising: a) contacting i) ethylene; ii) a catalyst system comprising (a) an N.sup.2-phosphinyl bicyclic amidine chromium salt complex or (b) a chromium salt and an N.sup.2-phosphinyl bicyclic amidine; ii) an organoaluminum compound, and iii) optionally an organic reaction medium; and b) forming an oligomer product in a reaction zone.

Methods of preparing oligomers of an olefin are provided. The methods can include providing a composition that includes an alkylaluminum compound, a chromium compound, and a hydrocarbon solvent. The hydrocarbon solvent can include n-undecane, a C8-C11 alkane compound having one branch, or a mixture thereof. The methods can further include contacting an olefin with the composition to form oligomers of the olefin. The olefin can include ethylene, and the oligomers of the olefin can include 1-hexene.

A process for making a poly alpha-olefin (PAO) having a relatively high vinylidene content (or combined vinylidene and tri-substituted vinylene content) and a relatively low vinyl and/or di-substituted vinylene content, as well as a relatively low molecular weight. The process includes: contacting a feed containing a C.sub.2-C.sub.32 alpha-olefin with a catalyst system comprising activator and a bis-cyclopentadienyl metallocene compound, typically a cyclopentadienyl-benzindenyl group 4 transition metal compound.

A three step method for the conversion of ethanol into fuels that can be utilized as full-performance military jet or diesel fuels. Embodiments of the invention further describe methods for the selective conversion of ethanol to full performance saturated hydrocarbon fuels that are suitable for both jet and diesel propulsion.

The present invention concerns a method for depolymerizing oxygenated polymer materials and the use of said method in the recycling of plastic materials and the preparation of aromatic compounds that can be used as fuel, synthesis intermediates and raw materials in the construction sectors and in the petrochemical, electrical, electronic, textile, aeronautical, pharmaceutical, cosmetics and agrochemical industries. The present invention also concerns the use of aromatic compounds obtained by the method for depolymerizing oxygenated polymer materials according to the invention, in the production of fuels, electronic components, plastic polymers, rubber, drugs, vitamins, cosmetic products, perfumes, food products, synthetic threads and fibres, synthetic leathers, glues, pesticides and fertilizers.