摘要:
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.
摘要:
The present invention provides a process for variably preparing mixtures of optionally alkyl-substituted BDO, GBL and THF by two-stage hydrogenation in the gas phase of C4 dicarboxylic acids and/or derivatives thereof, which comprises a) in a first step in the gas phase, hydrogenating a gas stream of C4 dicarboxylic acids and/or derivatives thereof over a catalyst at a pressure of from 2 to 100 bar and a temperature of from 200° C. to 300° C. in a first reactor in the presence of a catalyst in the form of shaped catalyst bodies having a volume of less than 20 mm3, said catalyst from 5 to 95% by weight of oxide of copper and from 5 to 95% by weight of an oxide having acidic sites, to give a stream mainly containing of optionally alkyl-substituted GBL and THF, b) removing any succinic anhydride formed by partial condensation, c) converting the products remaining predominantly in the gas phase in the partial condensation, THF, water and GBL, under the same pressure or under a pressure reduced by the pressure drops in the hydrogenation circuit and at a temperature of from 150 to 240° C., in a second reactor over a catalyst which ≦95% by weight of CuO and from 5 to 95% by weight of one or more oxides selected from the group of ZnO, Al2O3, SiO2, TiO2, ZrO2, CeO2, MgO, CaO, SrO, BaO, La2O3 and Mn2O3 to give a stream comprising a mixture of BDO, GBL and THF, d) removing the hydrogen from the products and recycling it into the hydrogenation, e) distillatively separating the products, THF, BDO, GBL and water, if appropriate recycling a GBL-rich stream into the second reactor or if appropriate discharging it, and working up BDO, THF and GBL distillatively, and setting the ratio of the products, THF, GBL and BDO, relative to one another within the range from 10 to 100% by weight of THF, from 0 to 90% by weight of GBL and from 0 to 90% by weight of BDO only by varying the temperatures in the two hydrogenation zones and also if appropriate the GBL recycle stream.
摘要:
The invention relates to a process for the continuous preparation of THF by reaction of a 1,4-butanediol-containing reaction mixture over a heteropolyacid catalyst which has not been predried, wherein the reaction mixture comprises 2-(4-hydroxybutoxy)tetrahydrofuran.
摘要:
The present invention provides a process for one-stage preparation of polyoxyalkylene glycols by copolymerizing tetrahydrofuran and alpha,omega-diols in the presence of a heteropolyacid and of a hydrocarbon, which comprises distilling water in a mixture with this hydrocarbon out of the copolymerization.
摘要:
The invention relates to a process for the continuous preparation of THF by reaction of a 1,4-butanediol-containing reaction mixture over a heteropolyacid catalyst which has not been predried, wherein the reaction mixture comprises 2-(4-hydroxybutoxy)tetrahydrofuran.
摘要:
The present invention relates to a process for preparing unsubstituted or C1-C4-alkyl-substituted gamma-butyrolactone by catalytic hydrogenation of maleic acid and/or its derivatives in the presence of chromium-free catalyst comprising from 10 to 80% by weight of copper oxide and from 10 to 90% by weight of at least one catalyst support selected from the group consisting of silicon dioxide, titanium dioxide, hafnium dioxide, magnesium silicate, activated carbon, silicon carbide, zirconium dioxide and alpha-aluminum oxide.
摘要:
In a process for the preparation of alcohols by catalytic hydrogenation of carbonyl compounds, the catalyst used is 0.01 to 50% by weight of rhenium and 0 to 20% by weight, in each case based on the total weight of the catalyst, of at least one further metal chosen from Zn, Cu, Ag, Au, Ni, Fe, Cr, V on oxidatively pretreated activated carbon as support.
摘要:
The invention provides an N-alkenyllactam having at least a 6-membered lactam ring, stabilized by phenothiazine and/or derivatives thereof, and a process for the stabilization of N-alkenyllactams.
摘要:
A process which isolates tetrahydrofuran from a stream of tetrahydrofuran, alkanol and high boilers, by: (a) separating off a first stream of tetrahydrofuran and alkanol as azeotrope in a first distillation stage; (b) feeding part of the first stream into a reactor for esterifying maleic anhydride, giving a second stream of tetrahydrofuran and monoalkyl maleate; (c) separating the second stream into a third stream of monoalkyl maleate and a fourth stream of tetrahydrofuran in a second distillation stage; (d) feeding the fourth stream of tetrahydrofuran from the second distillation stage and the part of the first stream from (a) which is not fed to the reactor into a third distillation stage to obtain a product stream of tetrahydrofuran and a sixth stream of tetrahydrofuran and alkanol; (e) recirculating the sixth stream from the third distillation stage into the first distillation stage or the reactor in (b).
摘要:
The present invention relates to a process for hydrogenating oligo- and/or polyesters obtainable by esterifying a DCS with a diol or diol mixture, said hydrogenation being performed in the presence of a catalyst whose catalyst precursor comprises copper oxide, aluminum oxide and at least one oxide of lanthanum, of iron, of tungsten, of molybdenum, of titanium or of zirconium, and to a process for preparing 1,6-hexanediol by catalytically hydrogenating ester mixtures which comprise, as main components, oligo- and polyesters of adipic acid and 6-hydroxycaproic acid, and are obtained by esterifying DCS with diols, especially 1,6-hexanediol or diol mixtures.