Embodiments of the present invention are directed to processes to improve rhodium accountability in continuous liquid recycle hydroformylation processes. In some embodiments, a process comprises contacting in a reaction zone reactants comprising mixed C8 olefins or mixed C9 olefins, hydrogen, and carbon monoxide in the presence of a catalyst comprising rhodium and an organomonophosphite ligand to form a reaction fluid, wherein the reaction fluid is introduced to a strip gas vaporizer to produce a product stream and a vaporizer tails stream, and wherein the vaporizer tails stream comprises at least 1.2 percent by weight C8 internal olefins or at least 1.3 percent by weight C9 internal olefins.

A method for preparing an aldehyde including forming a reaction product including an aldehyde by reacting an olefin-based compound with a synthetic gas in a hydroformylation reactor in the presence of a hydroformylation catalyst; introducing the reaction product including the aldehyde to a vaporizer; separating low-boiling point components of the reaction product from an upper part of a vaporizer catch pot included in the vaporizer; separating high-boiling point components of the reaction product from a lower part of the vaporizer catch pot; and recirculating at least a portion of the low-boiling point components separated from an upper part of the vaporizer catch pot back to the vaporizer.

Provided are a chromium catalyst precursor, an ethylene oligomerization catalyst including the same, and a method of preparing an ethylene oligomer using the same. More particularly, a chromium catalyst precursor which may oligomerize ethylene with high activity and high selectivity in spite of not using methylaluminoxane (MAO) or modified-methylaluminoxane (MMAO), an oligomerization catalyst including the same, and a method of preparing an ethylene oligomer using the same are provided.

Catalyst systems suitable for tetramerizing ethylene to form 1-octene may include a catalyst having a structure according to Formula (VI) or Formula (VII). In Formulas (VI) and (VII), X is a halogen, a (C.sub.2-C.sub.30) carboxylate, acetylacetonate, or a (C.sub.1-C.sub.30) hydrocarbyl; L.sub.1 is a neutral coordinating ligand; n is an integer from 0 to 6; Y is a (C.sub.6-C.sub.20)fluorine-substituted aryl, a (C.sub.6-C.sub.20)fluorine-substituted aryloxy, or a (C.sub.1-C.sub.20)fluorine-substituted alkoxy; and L∩L is a bidentate chelating ligand. The catalyst system may also include an aluminum containing agent which includes a reaction product of an organoaluminum compound and an antifouling compound. The antifouling compound may include one or more quaternary salts.

The invention describes single-site metal catalysts such as Pt single-site centers on powdered oxide supports with a 1,10-phenanthroline-5,6-dione (PDO) or bis-pyrimidyltetrazine (BMTZ) ligand on powdered MgO, Al.sub.2O.sub.3, or CeO.sub.2.

The present invention provides a method for efficiently manufacturing a phosphonate ester by phosphonylating an alcohol under mild conditions, and a method for manufacturing a phosphate ester. In the method for manufacturing a phosphonate ester of the present invention, a compound represented by the formula (1) is reacted with a compound represented by the formula (2) in the presence of a zinc catalyst to obtain a compound represented by the formula (3).

##STR00001##

X represents an organic group. R.sup.1 represents an alkyl group. R.sup.2 represents an organic group.

Described herein is a hydroformylation catalyst system and method useful for producing aldehydes from olefin substrates, without using carbon monoxide gas. The hydroformylation catalyst system includes a hydroformylation catalyst complex including a Group 9 metal complexed with a phosphine-based ligand; a syngas surrogate including formic acid and an anhydride compound, which forms carbon monoxide in situ; and hydrogen, which may derive from the syngas surrogate or not derived from the syngas surrogate. The method involves reacting the olefin substrate with a syngas surrogate in the presence of a hydroformylation catalyst complex, wherein the syngas surrogate forms carbon monoxide, and optionally hydrogen, in situ, and then isolating the aldehyde compound from a reaction mixture.

Provided are a tricyclodecane dimethanol composition, in which a ratio of structural isomers is controlled, and a preparation method thereof.

The invention concerns a process for the preparation of a catalyst for carrying out hydrogenation reactions in hydrotreatment and hydrocracking processes. Said catalyst is prepared from at least one mononuclear precursor based on molybdenum (Mo), in its monomeric or dimeric form, having at least one Mo═O or Mo—OR bond or at least one Mo═S or Mo—SR bond where [R=C.sub.xH.sub.y where x≧1 and (x−1)≦y≦(2x+1) or R=Si(OR′).sub.3 or R=Si(R′).sub.3 where R′=C.sub.x′H.sub.y′ where x′≧1 and (x′−1)≦y′≦(2x′+1)], and optionally from at least one promoter element from group VIII. Said precursors are deposited onto an oxide support which is suitable for the process in which it is used, said catalyst being dried at a temperature of less than 200° C. then advantageously being sulphurized before being deployed in said process.

The present disclosure relates to a method of using homogenous rhodium-BIPHEPHOS catalysts comprising for the hydroformylation of an allyl alcohol. In some aspects, the methods provided herein relate to the hydroformylation of allyl alcohol to produce 4-hydroxybutyraldehyde in a continuous process.