Abstract: The present invention provides a process for preparing 1,6-hexanediol by hydrogenating dialkyl adipates, alkyl 6-hydroxycaproates, 1,4-cyclohexanedione and 4-hydroxycyclohexan-1-one as ester mixtures comprising impurities, by a) freeing resulting the esterification mixture of excess alcohol and low boilers in a first distillation stage (alcohol removal), b) carrying out a separation of the bottom product in a second distillation stage into an ester fraction substantially free of 1,4-cyclohexanediols and a fraction comprising at least the majority of the 1,4-cyclohexanediols, c) catalytically hydrogenating the ester fraction substantially free of 1,4-cyclohexanediols (ester hydrogenation) and d) in a purifying distillation stage, obtaining 1,6-hexanediol from the hydrogenation effluent in a manner known per se, which comprises selectively hydrogenating the ester mixture before stage a) and/or before stage b) (purifying hydrogenation).

Abstract: Process for recovering cyclododecatriene (CDT) from a solution comprising CDT and high boilers such as deactivated catalyst and polymers, which comprises feeding the solution into a preheater and heating it, subsequently depressurizing it through a downstream pressure maintenance device and feeding the resulting two-phase mixture into a helical tube evaporator and there reducing the CDT content of the liquid phase by partial evaporation and discharging a gaseous product stream having an increased concentration of CDT.

Abstract: A biodiesel fuel mixture having a cetane number of >40, comprising a) from 1 to 100% by weight of biodiesel, b) from 0 to 98.9% by weight of diesel oil of fossil origin, c) from 0.1 to 20% by weight of polyoxyalkylene dialkyl ether of the formula RO(CH2O)nR ?in which R is an alkyl group having from 1 to 10 carbon atoms and n=from 2 to 10, and d) from 0 to 5% by weight of further additives.

Abstract: The present invention provides a process for preparing 1,6-hexanediol by hydrogenating dialkyl adipates, alkyl 6-hydroxycaproates, 1,4-cyclohexanedione and 4-hydroxycyclohexan-1-one as ester mixtures comprising impurities, by a) freeing resulting the esterification mixture of excess alcohol and low boilers in a first distillation stage (alcohol removal), b) carrying out a separation of the bottom product in a second distillation stage into an ester fraction substantially free of 1,4-cyclohexanediols and a fraction comprising at least the majority of the 1,4-cyclohexanediols, c) catalytically hydrogenating the ester fraction substantially free of 1,4-cyclohexanediols (ester hydrogenation) and d) in a purifying distillation stage, obtaining 1,6-hexanediol from the hydrogenation effluent in a manner known per se, which comprises selectively hydrogenating the ester mixture before stage a) and/or before stage b) (purifying hydrogenation).

Abstract: A process for the hydrogenation of an organic compound containing at least one carbonyl group comprises bringing the organic compound in the presence of hydrogen into contact with a shaped body which can be produced by a process in which (i) an oxidic material comprising copper oxide, aluminum oxide and aluminum oxide is made available (ii) pulverulent metallic copper, copper flakes, pulverulent cement, graphite or a mixture thereof is added to the oxidic material, and (iii) the mixture resulting from (ii) is shaped to form a shaped body.

Abstract: A process for hydrogenating an organic compound which has at least one carbonyl group, in which the organic compound is brought into contact in the presence of hydrogen with a shaped article which can be produced in a process in which (i) an oxidic material comprising copper oxide, aluminum oxide and at least one of the oxides of lanthanum, tungsten, molybdenum, titanium or zirconium is prepared, (ii) powdered metallic copper, copper flakes, powdered cement, graphite or a mixture thereof is added to the oxidic material, and (iii) the mixture resulting from (ii) is shaped to a shaped article.

Abstract: A process for preparing polyoxymethylene dimethyl ether of the formula H3CO(CH2O)nCH3 where n=2-10, in which methylal and trioxane are fed into a reactor and reacted in the presence of an acidic catalyst, wherein the amount of water introduced into the reaction mixture by methylal, trioxane and/or the catalyst is <1% by weight based on the reaction mixture. Preferably, a fraction comprising polyoxymethylene dimethyl ether where n=3 and 4 is obtained by distillation from the reaction mixture, and methylal, trioxane and polyoxymethylene dimethyl ether where n<3 and optionally n>4 are recycled into the reaction.

Abstract: The present invention relates to a process for preparing optically active hydroxy-, alkoxy-, amino-, alkyl-, aryl- or chlorine-substituted alcohols or hydroxy carboxylic acids having from 3 to 25 carbon atoms or their acid derivatives or cyclization products by hydrogenating the correspondingly substituted optically active mono- or dicarboxylic acids or their acid derivatives in the presence of a catalyst whose active component comprises a noble metal selected from the group of the metals Pt, Pd, Rh, Ir, Ag, Au and at least one further element selected from the group of the elements: Sn, Ge, Mo, W, Ti, Zr, V, Mn, Fe, Co, Ni, Cu, Zn, Ga, In, Pb, Bi, Cr, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu.

Abstract: The present invention relates to a process for preparing optically active hydroxy-, alkoxy-, amino-, alkyl-, aryl- or chlorine-substituted alcohols or hydroxy carboxylic acids having from 3 to 25 carbon atoms or their acid derivatives or cyclization products by hydrogenating the correspondingly substituted optically active mono- or dicarboxylic acids or their acid derivatives in the presence of a catalyst whose active component consists of rhenium or of rhenium and comprises at least one further element having an atomic number of from 22 to 83, with the provisos that a. the at least one further element having an atomic number of from 22 to 83 is not ruthenium and b.

Abstract: A process for hydrogenating an organic compound which has at least one carbonyl group, in which the organic compound is brought into contact in the presence of hydrogen with a shaped article which can be produced in a process in which (i) an oxidic material comprising copper oxide, aluminum oxide and at least one of the oxides of lanthanum, tungsten, molybdenum, titanium or zirconium is prepared, (ii) powdered metallic copper, copper flakes, powdered cement, graphite or a mixture thereof is added to the oxidic material, and (iii) the mixture resulting from (ii) is shaped to a shaped article.

Abstract: The present invention provides a process for preparing 1,6-hexanediol having a purity of ?99.5% by weight by catalytically dimerizing acrylic esters and catalytically hydrogenating the hexenedioic diesters obtained in this way to 1,6-hexanediol by a) dimerizing C1- to C8-acrylic esters in the presence of at least one rhodium compound to give mixtures of predominantly 2- and 3-hexenedioic diesters, b) hydrogenating the resulting dimerizing effluent in the presence of chromium-free catalysts comprising predominantly copper as the hydrogenation component and c) purifying the crude 1,6-hexanediol obtained in this way by fractional distillation.

Abstract: The present invention provides a process for preparing 1,6-hexanediol having a purity of ?99.5% by weight by catalytically dimerizing acrylic esters and catalytically hydrogenating the hexenedioic diesters obtained in this way to 1,6-hexanediol by a) dimerizing C1- to C8-acrylic esters in the presence of at least one rhodium compound to give mixtures of predominantly 2- and 3-hexenedioic diesters, b) hydrogenating the resulting dimerizing effluent in the presence of chromium-free catalysts comprising predominantly copper as the hydrogenation component and c) purifying the crude 1,6-hexanediol obtained in this way by fractional distillation.

Abstract: The present invention provides a process for preparing 2-cyclopentenones of the general formula: where R1 to R4 are each hydrogen atoms or are alkyl or alkenyl radicals having from 1 to 12 carbon atoms, cycloalkyl or cycloalkenyl radicals having from 5 to 7 carbon atoms, aralkylene or aryl radicals, by converting hexenedioic acids and/or their esters of the general formulae where R1 to R4 are each as defined above and R5 and R6 are each hydrogen atoms or are alkyl radicals having from 1 to 12 carbon atoms, cycloalkyl radicals having 5 or 6 carbon atoms, aralkyl or aryl radicals, at temperatures of from 150 to 450° C., over solid, oxidic catalysts, wherein the catalysts on an oxidic support material comprise from 0.01 to 5% by weight of at least one alkali metal oxide.

Abstract: The present invention provides a process for preparing 2-cyclopentenones of the general formula: 1