Abstract: Disclosed is a method for the catalytic hydrogenation of methylol alkanals of general formula (I), where R1 and R2 independently represent an additional methylol group or an alkyl group having with 1 to 22 carbon atoms, or an alkyl group with 1 to 22 C atoms, or an aryl group or aralkyl group with 6 to 33 carbon atoms, in the liquid phase on a hydrogenation catalyst. The inventive method is characterized in that a pH value ranging between 6.3 and 7.

Abstract: The invention relates to a method for increasing yield in the production of polyvalent alcohols, especially trimethylolpropane, obtained by condensing formaldehyde with a higher aldehyde. According to the inventive method, acid treatment is carried out on a mixture (high-boiling fraction) that is obtained by reprocessing, contains derivatives of said alcohols and has a higher boiling point than the respective alcohol, and the polyvalent alcohol is recovered from the acid-treated high-boiling fraction. The inventive method is characterised in that the water content of the high-boiling fraction amounts to between 20 and 90 wt. % in relation to the entire mixture of the high-boiling fraction and water.

Abstract: A process for removing trialkylammonium formate from methylolalkanes which have been obtained by condensation of formaldehyde with a higher aldehyde comprises decomposing trialkylammonium formate at elevated temperature in the presence of a hydrogen-containing gas over a catalyst comprising ruthenium supported on titanium dioxide. The process makes it possible to separate off the trialkylammonium formate from methylolalkanes prepared by the organic Cannizzaro process or by the hydrogenation process.

Abstract: The invention provides a process for preparing polyester polyols of polyhydric alcohols by mono- or polyesterification of at least one carboxylic acid having at least two acid groups and/or at least one derivative of a dicarboxylic acid with polyhydric alcohols, optionally with the addition of a catalyst, while removing the water of reaction, wherein the polyhydric alcohol used has a formaldehyde acetal content of less than 500 ppm.

Abstract: Trimethylolpropane is isolated from a reaction mixture which has been obtained by reaction of n-butyraldehyde with formaldehyde in the presence of a base and, if appropriate, hydrogenation of the resulting mixture by distilling the mixture by means of a dividing wall column or a distillation column with a precolumn or a distillation column with an after-column. The process has low capital costs and a low energy consumption and gives reduced formation of high-boiling by-products.

Abstract: Process for the catalytic hydrogenation of methylolalkanals of the formula where R1 and R2 are each, independently of one another, 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, wherein the pH of the hydrogenation feed is set to from 6.3 to 7.8 by addition of at least one tertiary amine.

Abstract: In a process for the catalytic hydrogenation of a polymethylolalkanal or a monomethylolalkanal of the formula (I) where R may be identical or different and are each a substituted or unsubstituted aliphatic hydrocarbon having from 1 to 22 carbon atoms, an aryl or arylalkyl group having from 6 to 22 carbon atoms or a methylol group, in the presence of a copper-containing catalyst, the hydrogenation feed comprising the polymethylolalkanal or monomethylolalkanal has a total content of metal ions of groups 3 to 14 of the Periodic Table of the Element of up to 5 ppm.

Abstract: A process is provided for improving the color number of polyhydric alcohols, especially trimethylolpropane, by catalytic hydrogenation, the polyhydric alcohol used in the hydrogenation having been purified by distillation following its preparation, wherein the hydrogenation is carried out in the presence of a macroporous supported heterogeneous catalyst containing, as the active metal, at least one metal of subgroups VII to X of the Periodic Table.

Abstract: The invention relates to a method for increasing yield in the production of polyvalent alcohols, especially trimethylolpropane, obtained by condensing formaldehyde with a higher aldehyde. According to the inventive method, acid treatment is carried out on a mixture (high-boiling fraction) that is obtained by reprocessing, contains derivatives of said alcohols and has a higher boiling point than the respective alcohol, and the polyvalent alcohol is recovered from the acid-treated high-boiling fraction. The inventive method is characterised in that the water content of the high-boiling fraction amounts to between 20 and 90 wt. % in relation to the entire mixture of the high-boiling fraction and water.

Abstract: The invention provides a process for preparing polyester polyols of polyhydric alcohols by mono- or polyesterification of at least one carboxylic acid having at least two acid groups and/or at least one derivative of a dicarboxylic acid with polyhydric alcohols, optionally with the addition of a catalyst, while removing the water of reaction, wherein the polyhydric alcohol used has a formaldehyde acetal content of less than 500 ppm.

Abstract: The invention provides a process for preparing polyetherols of polyhydric alcohols by reacting an alkylene oxide with the appropriate polyhydric alcohol in the presence of a base and in the presence or absence of a solvent, wherein the polyhydric alcohol used has a formaldehyde acetal content of less than 500 ppm.

Abstract: A method for removing trialkyl ammonium formate from a methylol alkanes obtained by condensation of formaldehyde with a higher aldehyde. The invention is characterized in that trialkyl ammonium formate is decomposed at a high temperature using catalysts containing at least one metal from groups 8-12 of the classification of elements in the presence of gas containing hydrogen. The method makes it possible to separate trialkyl ammonium formate according to the organic Cannizzaro method and according to the hydrogenation method.

Abstract: (Meth)acrylates of polyhydric alcohols are prepared by reacting (meth)acrylic acid and the corresponding polyhydric alcohol in the presence of at least one acidic catalyst and, if required, at least one polymerization inhibitor and in the presence or absence of a solvent, by a process in which the polyhydric alcohol used contains less than 500 ppm of bound formaldehyde.

Abstract: Trimethylolpropane is isolated from a reaction mixture which has been obtained by reaction of n-butyraldehyde with formaldehyde in the presence of a base and, if appropriate, hydrogenation of the resulting mixture by distilling the mixture by means of a dividing wall column or a distillation column with a precolumn or a distillation column with an after-column. The process has low capital costs and a low energy consumption and gives reduced formation of high-boiling by-products.

Abstract: The invention relates to a method for producing polymethylol compounds of formula (I), in which R represents a further methylol group or an alkyl group with between 1 and 22 C atoms or an aryl or alkyl aryl group with between 6 and 22 C atoms, by condensating aldehydes with between 2 and 24 C atoms with formaldehyde, using tertiary amines as catalysts, with a view to obtaining compounds of formula (II), in which R has the meaning assigned to it above. The invention further relates to a process for hydrogenating polymethylol compounds by condensation in stages.

Abstract: Formaldehyde is removed by distillation from reaction solutions containing a methlolated alkanal which was obtained from the reaction of formaldehyde with an alkanal which has at least one acidic hydrogen atom &agr; to the carbonyl function or from the reaction of a 2-alkylacrolein or acrolein with water and formaldehyde, by a process in which this reaction was carried out in the presence of catalytic amounts of organic amine. The process permits the improved removal of formaldehyde from the reaction mixture and furthermore facilitates the hydrogenation of the alkanals thus obtained to give polyols.

Abstract: In a process for the catalytic hydrogenation of a carbonyl compound or a mixture of two or more carbonyl compounds in the presence of catalyst tablets which comprise an inorganic, TiO2-containing support and, as active component, copper or a mixture of copper with at least one metal selected from the group consisting of zinc, aluminum, cerium, nobel metals and metals of transition group VIII and whose copper surface area is not more than 10 m2/g, the diameter d and/or the height h of the tablets is less than 3 mm.

Abstract: In a process for the catalytic hydrogenation of a carbonyl compound or a mixture of two or more carbonyl compounds in the presence of catalyst tablets which comprise an inorganic, TiO2-containing support and, as active component, copper or a mixture of copper with at least one metal selected from the group consisting of zinc, aluminum, cerium, nobel metals and metals of transition group VIII and whose copper surface area is not more than 10 m2/g, the diameter d and/or the height h of the tablets is less than 3 mm.

Abstract: The invention relates to a method for catalytically hydrating a poly- or monomethylol alkanal of the general formula (I), wherein R is the same or different and may represent a substituted or unsubstituted aliphatic hydrocarbon with 6 to 22 carbon atoms, an aryl or arylalkyl group with 6 to 22 carbon atoms or a methylol group, in the presence of a copper-containing catalyst. The inventive method is characterized in that the poly- or monomethylol alkanal containing batch to be hydrated has a total content of up to 5 ppm of metal ions of the groups 3 to 14 of the periodic system.

Abstract: Polymethylolalkanoic or monomethylolalkanoic acids of the formula (I) 1