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.

A process is developed for the hydroformylation of diisobutene, in which the diisobutene stream used is subjected to a distillation prior to the hydroformylation in order to enrich 2,4,4-trimethylpent-1-ene in the stream to be hydroformylated. The hydroformylation is carried out with synthesis gas in the presence of a homogeneous catalyst system that comprises at least Co or Rh and optionally a phosphorus-containing ligand.

A process isomerizes 2,4,4-trimethylpent-2-ene to 2,4,4-trimethylpent-1-ene over a heterogeneous catalyst based on a zeolite or an ion-exchange resin. The process includes providing an input stream containing 2,4,4-trimethylpent-2-ene and 2,4,4-trimethylpent-1-ene and performing the isomerization with the input stream using a heterogeneous catalyst based on a zeolite or an ion-exchange resin. A proportion of 2,4,4-trimethylpent-2-ene in the total stream is at least 25 mol % based on the total input stream.

A method for isomerizing methyltetrahydrophthalic anhydride includes the following processes. A liquid reactant is provided. Under a condition of injecting nitrogen gas, an alkaline catalyst is added into the liquid reactant for an isomerization reaction, so as to obtain an isomerization product. The liquid reactant includes 3-methyltetrahydrophthalic anhydride and 4-methyltetrahydrophthalic anhydride. Based on a total weight of the isomerization product being 100 wt %, an amount of a methyltetrahydrophthalic anhydride dimer is lower than 1.6 wt %.

A method of controlling a hydrocarbon conversion process is described. The method involves introducing a reactant into a reaction zone containing an ionic liquid catalyst. The reaction zone has at least two zones. The mass transfer resistance in the second zone is greater than the mass transfer resistance in the first zone.

A method for producing adamantane includes the steps of preparing a catalytic composition including an acidic ionic liquid and a co-catalyst and subjecting a tetrahydrodicyclopentadiene-containing component to isomerization in the presence of the catalytic composition to form adamantane. The acidic ionic liquid includes aluminum chloride and a quaternary onium compound selected from the group consisting of a quaternary ammonium halide, a quaternary phosphonium halide, and a combination thereof. The co-catalyst is an oxygen-containing reagent.

A method of controlling a hydrocarbon conversion process is described. The method involves introducing a reactant into a reaction zone containing an ionic liquid catalyst. The reaction zone has at least two zones. The mass transfer resistance in the second zone is greater than the mass transfer resistance in the first zone.

A catalyst comprising a NCN pincer ligand group VI complex is capable of being used as an olefin polymerization or isomerization catalyst that does not require an expensive cocatalyst. The complex has the NCN pincer ligand in a trianionic form with the group VI in the +3 oxidation state or the +4 oxidation state and complexed to an anionic hydrocarbon group, or the complex has the NCN pincer ligand in a dianionic form with the group VI in the +2 oxidation state. The complex is capable of initiating the polymerization of alkenes without an added activator. The presence of a water scavenger and activator or cocatalyst, such as triisobutylaluminum, increases the catalytic activity. The complex is capable of selectively isomerizing 1-alkenes to cis/trans 2-alkenes.

Isomerized olefin products are produced by contacting an olefin feed containing a C.sub.10 to C.sub.20 normal alpha olefin, a solid acid catalyst, and a C.sub.2 to C.sub.15 primary ester to form the isomerized olefin product. Typical primary esters used in the processes include formates and acetates. Linear olefin compositions are produced that contain at least 80 wt. % C.sub.10 to C.sub.20 linear internal olefins, less than 8 wt. % C.sub.10 to C.sub.20 normal alpha olefins, less than 8 wt. % dimers of C.sub.10 to C.sub.20 olefins, less than 15 wt. % C.sub.10 to C.sub.20 branched olefins, and at least 1 wt. % C.sub.2 to C.sub.15 primary ester and less than 8 wt. % secondary esters.

A multidentate phosphite ligand is used in the catalytic synthesis of adiponitrile. The ligand is represented by the following general formula (I). The method of catalytic synthesis of adiponitrile comprises primary hydrocyanation, isomerization, and secondary hydrocyanation reactions, wherein the catalyst adopted each comprises a phosphite ligand-nickel complex composed of a nickel precursor and a multidentate phosphite ligand. The ligand molecule has a higher electron cloud density, and the phosphorus content capable of participating in coordination in the ligand molecule per unit mass is higher, so that the catalytic activity of the catalyst is improved, and the amount of the catalyst is reduced. ##STR00001##