A method for producing an ?-olefin oligomer composition includes: an oligomerization step A1 of oligomerizing an ?-olefin with a metallocene catalyst to obtain an oligomer (a); a distillation separation step A2 of distilling and separating the oligomer (a) to obtain a high molecular weight fraction (a1) and a low molecular weight fraction (a2); an oligomerization step B1 of oligomerizing an ?-olefin oligomer containing the low molecular weight fraction (a2) with an acid catalyst to obtain an oligomer (b); and a mixing step C of mixing a portion of the oligomer (a) or a hydrogenated product thereof and a portion or a whole of the oligomer (b), an isomer thereof, or a hydrogenated isomer thereof.

A catalyst composition including the compound of Formula I as an internal electron donor, ##STR00001## wherein: R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are independently selected from a group consisting of hydrogen, straight, branched and cyclic alkyl and aromatic substituted and unsubstituted hydrocarbyl having 1 to 20 carbon atoms; R.sub.7 is selected from a group consisting of straight, branched and cyclic alkyl and aromatic substituted and unsubstituted hydrocarbyl having 1 to 20 carbon atoms; and R.sub.8 is selected from a group consisting of aromatic substituted and unsubstituted hydrocarbyl having 6 to 20 carbon atoms. Also disclosed is a process for preparing said polymerization catalyst composition; a polymerization catalyst system comprising said catalyst composition, a co-catalyst and optionally an external electron donor; a polyolefin obtainable by the process; and use of the compound of Formula I as in internal electron donor in catalysts for polymerization of olefins.

As described herein, nickel treated with sulfur provides a surprisingly effective source of nickel atoms for generating nickel-phosphorus-containing ligand complexes useful as hydrocyanation catalysts.

A catalyst composition comprises an inert hydrocarbon solvent, having dissolved therein a titanate of the formula Ti(OR).sub.4 wherein each R is the same or different, and is a hydrocarbon residue, and an organic aluminum compound, wherein a molar ratio of the organic aluminum compound and any alkene present in the catalyst composition is greater than one.

In one embodiment, the present application discloses a catalyst composition comprising: a) a reaction solvent or a reaction medium; b) organometallic nanoparticles comprising: i) a nanoparticle (NP) catalyst, prepared by a reduction of an iron salt in an organic solvent, wherein the catalyst comprises at least one other metal selected from the group consisting of Pd, Pt, Au, Ni, Co, Cu, Mn, Rh, Ir, Ru and Os or mixtures thereof; c) a ligand; and d) a surfactant; wherein the metal or mixtures thereof is present in less than or equal to 50,000 ppm relative to the iron salt.

A catalyst composition comprises an inert hydrocarbon solvent, having dissolved therein a titanate of the formula Ti(OR).sub.4 wherein each R is the same or different, and is a hydrocarbon residue, and an organic aluminum compound, wherein a molar ratio of the organic aluminum compound and any alkene present in the catalyst composition is greater than one.

Process for increasingly producing D-Lactide and meso lactide by depolymerizing by back biting polylactide (PLA) said process which comprises: (i) Depolymerizing polylactide into its corresponding dimeric cyclic esters by heating the polylactide in the presence of a catalyst system comprising a catalyst and a co-catalyst in a reaction zone at temperature and pressure at which the polylactide is molten; (ii) Forming a vapor product stream from the reaction zone; (iii) Removing the vapor product stream and optionally condense it; (iv) Recovering, either together or separately meso-lactide, D-lactide and L-lactide.

The present invention relates to the treatment of a promoted strong acid ion exchange resin for use as an acid catalyst with an antioxidant to protect the resin from oxidative degradation and the use of said treated promoted ion exchange resin catalyst in chemical production processes.

A process for preparing cyclic dehydration products from sugar alcohols is described. The process involve using a mixed-acid catalyst reaction mixture containing a reducing acid, having a pKa of about 1.0-1.5, and at least a strong Brnsted acid or a Lewis acid, having a pKa0, or both acids in a solution to dehydrate and ring close said sugar alcohol. Synergistically, the mixed-acid catalysis can produce greater amounts of the desired product at similar levels of compositional accountability than either of the component acid catalysts acting alone.

A method of isolating and purifying 1,2,5,6 hexanetetrol (HTO) from a reaction mixture containing HTO and other byproducts of a hydrogenation reaction of a sugar alcohol and/or a mono- or di-dehydrative product of a sugar alcohol is described. The method involves contacting the mixture comprising HTO and other C1-C6 alcohols and polyols with a resin material adapted for chromatography under conditions where HTO preferentially associates with the resin relative to other components in the mixture, and eluting HTO from said resin with a solvent.