A hydroformylation process can be used for short-chain olefins, especially C2 to C5 olefins, wherein the catalyst system is heterogenized on a support that contains a porous ceramic material. Systems can also be used for carrying out said process.

A process for preparing C.sub.5 aldehydes involves hydroformylation of butenes with synthesis gas in the presence of a homogeneous catalyst system and a solvent. It is a feature of the process that the aldehyde concentration in the reaction mixture is limited.

A process for producing branched alcohols through isomerization, hydroformylation and hydrogenation.

The present disclosure provides a stannous salt complex catalyst and a method for producing L-lactide by using the same. The catalyst is obtained by reacting stannous salt and phosphite in a solvent, which can effectively inhibit the oxidation of divalent stannous ions to tetravalent tin ions, effectively reduce the conversion rate of meso-lactide, increase the yield of L-lactide, and obtain nearly white L-lactide. In the crude lactide produced after the depolymerization reaction, the content of L-lactide is more than or equal to 95 %; the content of meso-lactide is less than or equal to 3.8 %, while ensuring that the color of the residual liquid is close to milky white.

Mixture of bisphosphites having an open and a closed outer unit and the use thereof as a catalyst mixture in hydroformylation.

A process for producing branched alcohols through isomerization, hydroformylation and hydrogenation.

The invention discloses a mixed Ni(II) complex containing bisoxazoline-derived nitrogen heterocyclic carbene ligand and phosphite ligand and application thereof; the chemical formula of the mixed Ni(II) complex is Ni(NHC)[P(OR).sub.3]X.sub.2, wherein R is ethyl or isopropyl, X is bromine or chlorine, and NHC is a bisoxazoline-derived nitrogen heterocyclic carbene ligand. In the presence of magnesium shavings, the mixed Ni(II) complex containing bisoxazoline-derived nitrogen heterocyclic carbene ligand and phosphite ligand of the present invention can catalyze low-activity chlorinated aromatic hydrocarbons and fluorinated aromatic hydrocarbons with chlorinated benzyl compounds, respectively, reductive cross-coupling reaction at a single temperature, generating a diarylmethane compound in one step, providing a new method for the synthesis of diarylmethane compounds.

The present invention generally relates to processes for the recovery of rhodium from a catalyst purge stream from a C6 or higher olefin hydroformylation process. In one embodiment, the process comprises (a) treating a catalyst-containing liquid purge stream from the hydroformylation process, wherein the catalyst comprises a precious metal and an organophosphorous ligand, with an oxidant in the presence of a separate liquid aqueous phase comprising a halide-free acid at a sufficient temperature to effect oxidation of a majority of the contained organophosphorous ligand, wherein the halide-free acid is a C1-C6 organic acid or phosphorous acid; (b) recovering the aqueous phase; (c) contacting the aqueous phase with a separate organic phase by mixing the two phases under a syngas atmosphere, wherein the separate organic phase comprises water-insoluble, hydrolysable organophosphorous ligand and recycled olefin from a hydroformylation process; and (d) separating the organic phase to be recycled back to a hydroformylation process.

The present invention refers to the use of an epoxide in order to reduce the formation of heavy ends in a continuous hydroformylation process, where an olefin or olefin mixture is reacted with carbon monoxide and hydrogen in the presence of a rhodium complex catalyst, comprising at least one organobisphosphite ligand, in order to produce an aldehyde. Said epoxide is added to the reaction mixture in an amount of 0.01-1.5 wt %, reducing the formation of heavy ends by 10-80%.

Use of a method for reduction of heavy end formation and catalyst loss in a hydroformylation process, wherein the method comprises the steps; a) Reacting an olefin and syngas in a reactor assembly (1) utilizing at least one catalyst and at least one ligand, b) Separating an obtained aldehyde from a mixture of aldehyde, catalyst, ligand and early heavy ends in a distillation unit (2), c) Entering the mixture of catalyst, ligand, early heavy ends and rest aldehyde into a short residence time evaporator unit (3) having at least a first rest aldehyde stripper stage (3a) and at least one last early heavy ends stripper stage (3b). Said evaporator units (3) being of a falling film and/or wiped film type, d) That the catalyst/ligand mixture from a lower end (3b1) of the at least one last early heavy ends stripping stage (3b) is entered into a cooling unit (4) immediately after stripping of early heavy ends.