Abstract: A process for preparing toluene derivatives of the formula I, where R1, R2 and R3 independently of one another are hydrogen, halogen, C1–C6-alkyl, hydroxyl or C1–C6-alkoxy, by hydrogenating benzaldehydes and/or benzyl alcohols of the formula II, with hydrogen in the presence of a catalyst, which is described in more detail in the description.

Abstract: Formic acid is at least partly removed from an aqueous solution comprising formic acid, cyclohexanone and cyclohexanol by decomposition over certain decomposition catalysts. The method is preferably used for processing reaction products from the oxidation of cyclohexane and comprises: (i) extracting a product gas mixture obtained in the oxidation of cyclohexane with an aqueous scrubbing liquid, (ii) separating the aqueous solution obtained in (i) by distillation into an aqueous solution comprising formic acid, cyclohexanone and cyclohexanol together with further minor organic components and a carboxylic acid mixture (iii) removing the formic acid at least partially from the aqueous solution obtained in (ii) by decomposition, and (iv) further processing the aqueous solution obtained in (iii) to give epsilon-caprolactam, or using the aqueous solution obtained in (iii) as scrubbing liquid in (i).

Abstract: In a process for preparing alcohols by catalytic hydrogenation of carbonyl compounds over a catalyst comprising rhenium on activated carbon, the catalyst used comprises rhenium (calculated as metal) in a weight ratio to the activated carbon of from 0.0001 to 0.5, platinum (calculated as metal) in a weight ratio to the activated carbon of from 0.0001 to 0.5 and, if appropriate, at least one further metal selected from among Zn, Cu, Ag, Au, Ni, Fe, Ru, Mn, Cr, Mo, W and V in a weight ratio to the activated carbon of from 0 to 0.25, and the activated carbon has been nonoxidatively pretreated. It is also possible to prepare ethers and lactones if the hydrogen pressure is not more than 25 bar. In this case, the activated carbon in the catalyst may also have been nonoxidatively pretreated.

Abstract: In a process for preparing alcohols by catalytic hydrogenation of carbonyl compounds over a catalyst comprising rhenium on activated carbon, the catalyst used comprises rhenium (calculated as metal) in a weight ratio to the activated carbon of from 0.0001 to 0.5, platinum (calculated as metal) in a weight ratio to the activated carbon of from 0.0001 to 0.5 and, if appropriate, at least one further metal selected from among Zn, Cu, Ag, Au, Ni, Fe, Ru, Mn, Cr, Mo, W and V in a weight ratio to the activated carbon of from 0 to 0.25, and the activated carbon has been nonoxidatively pretreated It is also possible to prepare ethers and lactones if the hydrogen pressure is not more than 25 bar. In this case, the activated carbon in the catalyst may also have been nonoxidatively pretreated.

Abstract: A process for preparing 1,6-hexanediol from a carboxylic acid mixture comprising adipic acid, 6-hydroxycaproic acid and small amounts of 1,4-cyclohexanediols which is obtained as by-product in the oxidation of cyclohexane to cyclohexanone/cyclohexanol after water extraction of the reaction mixture followed by extraction with aqueous sodium hydroxide solution, by esterification of the acids and hydrogenation comprises a) liberating the carboxylic acids from the alkaline extract by addition of a mineral acid, b) fractionating the organic phase comprising carboxylic acids to give a distillate comprising the low molecular weight monocarboxylic acids and a residue comprising adipic acid and 6-hydroxycaproic acid, c) reacting the monocarboxylic an dicarboxylic acids present in the aqueous dicarboxylic acid mixture with a low molecular weight alcohol to give the corresponding carboxylic esters, d) freeing the esterification mixture obtained of excess alcohol and low boilers in a first distillation step, e) frac