Abstract:
A process for catalytically hydrogenating methylolalkanals of the general formula (I) in which R1 and R2 each signifies, independent of one another, a further methylol group or an alkyl group having from 1 to 22 C atoms, or an aryl or aralkyl group having from 6 to 33 C atoms, in the liquid phase with hydrogen over a hydrogenation catalyst, characterized by the use of the molar ratio of hydrogen to methylolalkanal of greater than 1.
Abstract:
The invention relates to a method for distilling an aqueous polymethylol mixture, comprising a polymethylol of formula (I), where R independently = a further methylol group, or 1 to 22 C alkyl, or a 6 to 22 C aryl or aralkyl group, a tertiary amine, water and the adduct of tertiary amine and formic acid, (amine formate), characterised in that the distillation is carried out in a distillation column connected to an evaporator at the kettle, wherein the kettle temperature is maintained above the boiling point of the mono-ester of formic acid and polymethylol (polymethylol formate) formed during the distillation. The invention further relates to a composition comprising polymethylol and 1 to 10,000 ppm by weight of polymethylol formate and the use thereof.
Abstract:
The invention relates to a catalyst provided in the form of an extrudate, which contains 5 to 85 % by weight of copper oxide and comprises, in the active material and as binders, the same oxidic carrier material. The invention also relates to the use of the catalyst for hydrogenating carbonyl compounds.
Abstract:
A process for catalytically hydrogenating methylolalkanals of the general formula (I) in which R1 and R2 are each independently a further methylol group or an alkyl group having from 1 to 22 carbon atoms or an aryl or aralkyl group having from 6 to 33 carbon atoms, in the liquid phase over a hydrogenation catalyst, which comprises setting a pH of from 7.0 to 9.0 in the hydrogenation effluent by adding at least one tertiary amine, an inorganic base or an inorganic or organic acid to the hydrogenation feed.
Abstract:
The invention relates to hydroxy pivalin aldehyde, which is produced by the aldolization of isobutyraldehyde with formaldehyde and subsequent processing of the reaction product by distillation, wherein the reaction product is fed to a distillation column, which is operated at a top pressure ranging between 0.5 and 1.5 bar and in which a two-stage condensation process is provided in the top region. In this process, the vapors are first fed to a partial condenser operated at a temperature ranging between 50 and 80ºC, the condensate of which is returned at least partially to the distillation column, and the vapors that are not condensed in the partial condenser are fed to a downstream condenser operated at a temperature ranging between -40º and +30ºC, the condensate of which is discharged at least partially.