Abstract: The disclosure involves a process for preparing butadiene from n-butane. In the process, n-butane is first dehydrogenated autothermally under nonoxidative conditions to form a gas stream. The gas stream is then oxidatively dehydrogenated to form a second gas stream. From the second gas stream, a third gas stream containing n-butane, 2-butene and butadiene is obtained. From the third gas stream, a butadiene/butaine product stream is obtained and remaining n-butane and 2-butene is recycled into the first dehydrogenation zone.

Abstract: The disclosure involves a process for the preparation of butadiene and 1-butene. The process includes at least a first catalytic dehydrogenation of n-butane to obtain a gas stream which is followed by at least a second oxidative dehydrogenation to form a second gas stream. The second gas stream is then subjected to distillation and isomeration steps to obtain butadiene and 1-butene.

Abstract: A process for preparing 1-butene, which includes nonoxidatively, catalytically dehydrogenating n-butane to obtain a product gas stream of n-butane, 1-butene, 2-butene, butadiene, hydrogen, and secondary constituents; removing hydrogen and the secondary constituents to obtain a C4 product gas stream; separating the C4 product stream into a recycle stream of n-butane and a stream of 1-butene, 2-butene and butadiene by extractive distillation, and recirculating the recycle stream to the dehydrogenation zone; introducing the 1 -butene, 2-butene and butadiene stream into a selective hydrogenation zone and selective hydrogenation of butadiene to 1-butene and/or 2-butene to obtain a stream of 1-butene and 2-butene; introducing the 1-butene and 2-butene stream, and a circulating stream of 1-butene and 2-butene into a distillation zone and isolation of a product stream; and introducing the 2-butene-containing stream into an isomerization zone to obtain a circulating stream of 1-butene and 2-butene, and recirculating t

Abstract: The disclosure relates to a process for preparing butadiene. The process involves nonoxidatively catalytically dehydrogenating butane to obtain a product gas stream containing butane, 1-butene, 2-butene, butadiene, hydrogen and secondary constituents. The 1-butene and 2-butene of the product gas stream is then oxidatively dehydrogenated to give a second gas stream containing butane,2-butene, butadiene, hydrogen, steam and secondary constituents. Next, the butane,2-butene and butadiene are separated from the second gas stream and the butane and 2-butene are then separated from the butadiene product. The butane and 2-butene are then recycled into the nonoxidative catalytic dehydrogenating zone.

Abstract: A process is described for hydrocyanating 1,3-butadiene over at least one nickel(0) complex having phosphorus ligands as a catalyst, wherein the 1,3-butadiene is used in a mixture with n-butane and the mixture contains from 60 to 90% by volume of 1,3-butadiene and from 40 to 10% by volume of n-butane.

Abstract: The present invention provides a process for preparing a supported catalyst (catalyst C) having a support (support S) selected from among oxides, phosphates, silicates, carbides, borides and nitrides of main group elements and elements of transition groups VI and II and mixtures of the abovementioned compounds and an active component (activator A) comprising one or more compounds containing one or more elements of transition groups V, VI and VII customary for the catalysis of metathesis reactions.

Abstract: A C4-olefin mixture having a 1,3-butadiene content of from 100 to 500 ppm and a content of 1,2-dienes of less than 10 ppm is described. The present invention further provides a process for preparing this C4-olefin mixture and provides for its use in a metathesis reaction for preparing 2-pentene and/or 3-hexene.

Abstract: Process for preparing a compound having a nonaromatic C—C double or triple bond (compound A) from another compound or a mixture of other compounds having a nonaromatic C—C double or triple bond (compound B), which comprises bringing the compound (B) into contact with a heterogeneous catalyst comprising carbides or oxycarbides of a transition element at from 50 to 500° C.

Abstract: Process for producing a supported catalyst which comprises at least 75% by weight of Al2O3, whose proportion of Al2O3 in the delta or theta modification is, based on the proportion of Al2O3, at least 1% and which comprises a rhenium compound and, if appropriate, a promoter as active component (A), which comprises a) converting a customary support (S) which comprises at least 75% by weight of Al2O3 and to which a promoter may, if appropriate, have been applied is converted into a modified support (S) whose proportion of Al2O3 in the delta or theta modification is, based on the proportion of Al2O3, at least 1% by calcining the customary support (S) at a temperature of from 750 to 1100°C., b) producing a supported catalyst precursor from the modified support (S) by applying the active component (A) comprising the rhenium compound to the modified support (S) and c) calcining the supported catalyst precursor at a temperature of from 500 to 750° C.

Abstract: Supported catalyst comprising a support (S) in which Al2O3 is present in a proportion of at least 75% by weight and rhenium compounds as active component (A), wherein the maximum of the distribution function of the pore diameters in the mesopore range is at from 0.008 to 0.050 ?m.

Abstract: The invention relates to a process for preparing butadiene from n-butane having the steps of A) providing a feed gas stream a comprising n-butane; B) feeding the feed gas stream a comprising n-butane into at least one first dehydrogenation zone and nonoxidatively catalytically dehydrogenating n-butane to obtain a product gas stream b comprising n-butane, 1-butene, 2-butene, butadiene, hydrogen, low-boiling secondary constituents and in some cases steam; C) feeding the product gas stream b of the nonoxidative catalytic dehydrogenation and an oxygenous gas into at least one second dehydrogenation zone and oxidatively dehydrogenating 1-butene and 2-butene to obtain a product gas stream c comprising n-butane, 2-butene, butadiene, hydrogen, low-boiling secondary constituents and steam, said product gas stream c having a higher content of butadiene than the product gas stream b; D) removing hydrogen, the low-boiling secondary constituents and steam to obtain a C4 product gas stream d substantially consisting of n-

Abstract: The invention relates to a process for preparing butadiene from n-butane having the steps of A) providing a feed gas stream a comprising n-butane; B) feeding the feed gas stream a comprising n-butane into at least one first dehydrogenation zone and nonoxidatively catalytically dehydrogenating n-butane to obtain a product gas stream b comprising n-butane, 1-butene, 2-butene, butadiene, hydrogen, low-boiling secondary constituents and in some cases steam; C) feeding the product gas stream b of the nonoxidative catalytic dehydrogenation and an oxygenous gas into at least one second dehydrogenation zone and oxidatively dehydrogenating 1-butene and 2-butene to obtain a product gas stream c comprising n-butane, 2-butene, butadiene, hydrogen, low-boiling secondary constituents and steam, said product gas stream c having a higher content of butadiene than the product gas stream b; D) removing hydrogen, the low-boiling secondary constituents and steam to obtain a C4 product gas stream d substantially consisting of

Abstract: A) Provision of an n-butane-containing feed gas stream a; B) introduction of the n-butane-containing feed gas stream a into at least one dehydrogenation zone and nonoxidative catalytic dehydrogenation of n-butane to give a product gas stream b comprising n-butane, 1-butene, 2-butene, butadiene, low-boiling secondary constituents, hydrogen and possibly water vapor, C) removal of hydrogen, the low-boiling secondary constituents and, if appropriate, water vapor to give a C4 product gas stream c consisting essentially of n-butane, 1-butene, 2-butene and butadiene; D) introduction of the C4 product gas stream c consisting essentially of n-butane, 1-butene, 2-butene and butadiene into a selective hydrogenation zone and selective hydrogenation of butadiene to 1- and/or 2-butene to give a stream d consisting essentially of n-butane, 1-butene and 2-butene; E) separation of the stream d into a desired product stream e1 consisting essentially of 1-butene and a recycle stream e2 consisting essentially of 2-butene and n

Abstract: The invention relates to a process for preparing butadiene from n-butane having the steps of A) providing a feed gas stream a comprising n-butane; B) feeding the feed gas stream a comprising n-butane into at least one first dehydrogenation zone and nonoxidatively catalytically dehydrogenating n-butane to obtain a product gas stream b comprising n-butane, 1-butene, 2-butene, butadiene, hydrogen, low-boiling secondary constituents and in some cases steam; C) feeding the product gas stream b of the nonoxidative catalytic dehydrogenation and an oxygenous gas into at least one second dehydrogenation zone and oxidatively dehydrogenating n-butane, 1-butene and 2-butene to obtain a product gas stream c comprising n-butane, 2-butene, butadiene, low-boiling secondary constituents and steam, said product gas stream c having a higher content of butadiene than the product gas stream b; D) removing the low-boiling secondary constituents and steam to obtain a C4 product gas stream d substantially consisting of n-butane, 2-

Abstract: A) Provision of an n-butane-containing feed gas stream a; B) introduction of the n-butane-containing feed gas stream a into at least one dehydrogenation zone and nonoxidative catalytic dehydrogenation of n-butane to give a product gas stream b comprising n-butane, 1-butene, 2-butene, butadiene, hydrogen, low-boiling secondary constituents and possibly water vapor; C) removal of hydrogen, the low-boiling secondary constituents and, if appropriate, water vapor to give a C4 product gas stream c consisting essentially of n-butane, 1-butene, 2-butene and butadiene; D) separation of the C4 product gas stream c into a recycle stream d1 consisting essentially of n-butane and a stream d2 comprising 1-butene, 2-butene and butadiene by extractive distillation and recirculation of the recycle stream d1 consisting essentially of n-butane to the dehydrogenation zone; E) introduction of the stream d2 comprising 1-butene, 2-butene and butadiene into a selective hydrogenation zone and selective hydrogenation of butadiene to

Abstract: The invention relates to a process for preparing polyisocyanates by reacting organic amines with phosgene, wherein the reaction is carried out in at least three stages, with the first stage being carried out in a mixing apparatus, the second stage in at least one residence apparatus and the third stage in at least one separation apparatus and the pressure in each successive stage being lower than that in the previous stage.

Abstract: The invention relates to a process for preparing polyisocyanates by reacting primary amines with phosgene, which comprises the steps a) mixing the amine with the phosgene, b) reacting the amine with the phosgene in a residence reactor and, if desired, c) transferring the output from the reactor of step b) into a distillation column, wherein the residence reactor in step b) is configured as a tube reactor.

Abstract: The present invention relates to a continuous process for preparing isocyanates by reacting primary amines with phosgene, wherein the reaction is carried out in a cascade of at least two tube reactors and the gas phase formed in the reaction is separated off in a phase separator after each reactor and only the liquid phase is passed to the next reactor or to product purification and the reaction volume of the first tube reactor is only a fraction of the total reaction volume.

Abstract: A continuous process for preparation of a polyether polyol in a reactor includes introducing an initial starter/catalyst mixture into the reactor. The initial starter/catalyst mixture comprises an initial starter and a catalyst with the catalyst selected from aluminum phosphate catalysts and/or aluminum phosphonate catalysts and/or residues of these catalysts. In this continuous process, one or more alkylene oxide is continuously introduced into the reactor. Additional amounts of the catalyst and a continuous starter are also continuously introduced into the reactor. The polyether polyol prepared herein is continuously withdrawn from the reactor.

Abstract: The present invention relates to a continuous process for preparing isocyanates by reacting primary amines with phosgene, wherein the reaction is carried out in a cascade of at least two tube reactors and the gas phase formed in the reaction is separated off in a phase separator after each reactor and only the liquid phase is passed to the next reactor or to product purification and the reaction volume of the first tube reactor is only a fraction of the total reaction volume.