A renewable biofuel based on a highly efficient batch catalysis methodology for conversion of 1-butene to a new class of potential jet fuel blends. By tuning the catalyst and then using the dimer produced, the carbon use is about 95% or greater. This latter point will be particularly important in the future, where the source of raw materials (i.e., biomass/biofeedstock) is limited.

The present invention relates to a ligand compound, an organic chromium compound, a catalyst system for ethylene oligomerization, a preparation method thereof, and an ethylene oligomerization method using the same. The catalyst system for ethylene oligomerization according to the present invention is used to prepare a low-density polyethylene in one reactor by using a small amount of comonomers such as alpha-olefin or by using only ethylene without comonomers, because it maintains high catalytic activity and high alpha-olefin selectivity even though supported on a support.

A modified solid polyalkylaluminoxane is provided, which is capable of providing α-olefin suppressing adhesion of any polymer produced as a by-product onto the reactor wall and the stirrer, and which is capable of providing a highly active olefin oligomerization reaction catalyst. An olefin oligomerization reaction catalyst containing the modified solid polyalkylaluminoxane is also provided. The modified solid polyalkylaluminoxane for olefin oligomerization reactions contains structural units represented by general formula (a) and structural units represented by general formula (b), whose median diameter is equal to or larger than 0.1 μm and equal to or smaller than 50 μm,

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in which R′ in the general formula (a) represents an alkyl group having 1 to 20 carbon atoms, and R″ in the general formula (b) represents a halogenated alkoxy group having 1 to 20 carbon atoms or a halogenated aryloxy group having 6 to 20 carbon atoms.

Processes for producing an α,β-unsaturated carboxylic acid, such as acrylic acid, or a salt thereof, using treated solid oxides are disclosed. The treated solid oxides can be calcined solid oxides, metal-treated solid oxides, or metal-treated chemically-modified solid oxides, illustrative examples of which can include sodium-treated alumina, calcium-treated alumina, zinc-treated alumina, sodium-treated sulfated alumina, sodium-treated fluorided silica-coated alumina, and similar materials.

Disclosed herein are a chromium compound represented by Formula 1a or 1b and a catalyst system including the same, exhibiting superior catalytic activity in an olefin trimerization reaction:

[{CH.sub.3(CH.sub.2).sub.3CH(CH.sub.2CH.sub.3)CO.sub.2}.sub.2Cr(OH)]  [Formula 1a]

[{CH.sub.3CH.sub.2CH(CH.sub.2CH.sub.3)CO.sub.2}.sub.2Cr(OH)]  [Formula 1b].

The present invention relates to an oligomerization catalyst including a transition metal or transition metal precursor, a halogen-substituted organic ligand, and a heteroatom ligand, and to a method for selectively preparing 1-hexene or 1-octene from ethylene using the catalyst.

The present specification relates to an olefin oligomerization method and specifically to an olefin oligomerization method comprising the step of subjecting an olefin to a multimerization reaction by controlling a reaction temperature such that the weight ratio of 1-hexene to 1-octene within a product comprising 1-hexene and 1-octene has a predetermined value, in the presence of an oligomerization catalyst system comprising a ligand compound, a transition metal compound, and a cocatalyst, wherein the predetermined value for the weight ratio of 1-hexene to 1-octene within the product is selected in a range of 1:0.5 to 1:7. By the method, 1-hexene and 1-octene can be produced in a desired ratio.

The present disclosure provides a Lewis acid-base pair catalytic initiator and an application thereof. The Lewis acid-base pair catalytic initiator includes a Lewis acid and a Lewis base, the Lewis acid having a structural general formula as shown in formula (I) and the Lewis base having a structural general formula as shown in formula (II); wherein: the A is selected from element Baron or element Aluminum; the R.sub.1, R.sub.2, R.sub.3, R.sub.4 are independently selected from alkyl, alkoxy, aryl or halogen groups; the alkyl or alkoxy have a carbon number being equal to or greater than 1 to equal to or less than 16; the aryl contains substituents with the number being equal to or less than 5, the substituents being selected from methyl, methoxy or halogen; n is selected from an integer from 1 to 16.

Catalyst compositions and processes for the oligomerization of ethylene to 1-hexene are described. The catalyst composition includes a triamino bisphospino (NPNPN) ligand system with specific phosphorous and nitrogen ligands. The terminal nitrogen atoms include linear alkyl hydrocarbons that differ in the number of carbon atoms by 3.

The present invention discloses a continuous calcination vessel which can be used to prepare calcined chemically-treated solid oxides from solid oxides and chemically-treated solid oxides. A process for the continuous preparation of calcined chemically-treated solid oxides is also provided. Calcined chemically-treated solid oxides disclosed herein can be used in catalyst compositions for the polymerization of olefins.