Abstract: A process can be used for preparing sodium and potassium alkoxides. The process is characterized by two simultaneously implemented but spatially separated reactions of an alcohol ROH with NaOH, and ROH with KOH, to give sodium alkoxide and potassium alkoxide, respectively. The vapours formed in this case contain the alcohol used and water. The vapours are combined, and the resulting mixed vapour is fed to a common distillation with recovery of the alcohol.

Abstract: A process produces sodium and/or potassium alkoxides in countercurrent by reactive rectification. Alcohol is reacted in countercurrent with the respective alkali metal hydroxide. The vapours containing alcohol and water are separated into at least two serially arranged rectification columns. The energy of the vapour obtained in the first rectification is utilized for operating the second rectification. This specific energy integration coupled with establishing a certain pressure difference in the two rectification stages makes it possible to cover a particularly large proportion of the energy required for the rectification through electricity and to save heating steam.

Abstract: A method can be used for producing alkali metal alcoholates in counter flow by reactive rectification. The alkali metal is selected from sodium and potassium. In a first part of the method, the alcohol is converted in counter flow with the respective alkali metal hydroxide. In a second part of the method, the mixture of alcohol and water obtained is separated in a rectification column, and the alcoholic vapour arising is condensed, as a result of which the temperature thereof increases. The energy dissipated during cooling of the condensed vapour is then used in the first part of the method. This permits an energy-efficient production of the alkali metal alcoholates concerned.

Abstract: A method can be used for producing alkali metal alcoholates in counter flow by reactive rectification. The alkali metal is selected from sodium and potassium. In a first part of the method, the alcohol is converted in counter flow with the respective alkali metal hydroxide. In a second part of the method, the mixture of alcohol and water obtained is separated in a rectification column, and the alcoholic vapour arising is condensed, as a result of which the temperature thereof increases. The energy dissipated during cooling of the condensed vapour is then used in the first part of the method. This permits an energy-efficient production of the alkali metal alcoholates concerned.

Abstract: A process can be used for preparing sodium and potassium alkoxides. The process is characterized by two simultaneously implemented but spatially separated reactions of an alcohol ROH with NaOH, and ROH with KOH, to give sodium alkoxide and potassium alkoxide, respectively. The vapours formed in this case contain the alcohol used and water. The vapours are combined, and the resulting mixed vapour is fed to a common distillation with recovery of the alcohol.

Abstract: A process produces sodium and/or potassium alkoxides in countercurrent by reactive rectification. Alcohol is reacted in countercurrent with the respective alkali metal hydroxide. The vapours containing alcohol and water are separated in at least two serially arranged rectification columns. The energy of the vapour obtained in the second rectification is utilized for operating the first rectification. This specific energy integration coupled with establishing a certain pressure difference in the two rectification stages makes it possible to cover a particularly large proportion of the energy required for the rectification through heating steam and minimizes the use of electricity.

Abstract: A process produces sodium and/or potassium alkoxides in countercurrent by reactive rectification. Alcohol is reacted in countercurrent with the respective alkali metal hydroxide. The vapours containing alcohol and water are separated into at least two serially arranged rectification columns. The energy of the vapour obtained in the first rectification is utilized for operating the second rectification. This specific energy integration coupled with establishing a certain pressure difference in the two rectification stages makes it possible to cover a particularly large proportion of the energy required for the rectification through electricity and to save heating steam.

Abstract: A process for preparing isobutene by dissociation of MTBE, including: a) reaction of isobutene-containing hydrocarbon mixtures, with methanol, present in one or more methanol-containing streams, over acidic ion exchangers to give a stream, containing MTBE and TBA; b) separation of a stream containing MTBE and TBA, from a stream by distillation; c) dissociation of a stream in the gas phase over a heterogeneous catalyst to give a stream containing at least isobutene, methanol, MTBE and water and possibly TBA, d) separation of a stream by distillation to give a stream containing in each case more than 50% by mass of the amounts of methanol, TBA and water present in another stream and a stream containing isobutene, e) separation of water from stream to below 1% by mass by distillation to give a stream, f) total or partial recirculation of the methanol-containing stream.

Abstract: The invention relates to a process for regenerating catalysts containing mixed oxides from the group of alkali metal and/or alkaline earth metal oxides, aluminium oxide and silicon oxide, characterized in that the regeneration comprises the following features: i) treatment of the catalyst in situ, ii) contacting of the catalyst with water, iii) treatment of the catalyst within a temperature range from 100 to 400° C., iv) treatment of the catalyst within a pressure range from 0.1 to 2 MPa, v) treatment of the catalyst over a period of 0.1 to 24 h, vi) treatment of the catalyst with a specific catalyst hourly space velocity of 0.1 to 100 h?1.

Abstract: The present invention relates to a process for efficient purification of MTBE-containing mixtures and for preparation of isobutene by cracking of MTBE-containing mixtures.

Abstract: The invention relates to a process for preparing substituted or unsubstituted 1,7-diolefins by hydrodimerizing non-cyclic olefins having at least two conjugated double bonds in the presence of a reducing agent and of a catalyst, wherein the catalyst used is a metal-carbene complex.

Abstract: A process for preparing isobutene including cleaving a mixture obtained from an MTBE-containing feedstock and/or an MTBE-containing stream, affording a stream of reaction products consisting of isobutene, methanol, MTBE and by-products, the latter consisting of a1) high boilers having a boiling range above 55° C. at a pressure of 0.1 MPa; a2) medium boilers having a boiling range of 12 to 55° C. at a pressure of 0.1 MPa; and a3) low boilers having a boiling range below 12° C. at a pressure of 0.1 MPa; distillatively separating into a stream which contains the isobutene product and low boilers, and a stream which contains MTBE, methanol, medium boilers and high boilers; distillatively separating to obtain an MTBE-containing stream and a methanol-containing high boiler stream; recycling an MTBE-containing stream in which the medium boilers being removed completely or partially before recycling.

Abstract: The present invention relates to a process for efficient purification of MTBE-containing mixtures and for preparation of isobutene by cracking of MTBE-containing mixtures.

Abstract: The invention relates to a process for preparing ETBE from technical mixtures which comprise at least 1-butene, isobutene, n-butane and 2-butenes, by reacting the isobutene present, distillatively removing a fraction comprising 1-butene and isobutene and again reacting the isobutene present therein to give ETBE.

Abstract: The invention relates to a process for regenerating catalysts containing mixed oxides from the group of alkali metal and/or alkaline earth metal oxides, aluminium oxide and silicon oxide, characterized in that the regeneration comprises the following features: i) treatment of the catalyst in situ, ii) contacting of the catalyst with water, iii) treatment of the catalyst within a temperature range from 100 to 400° C., iv) treatment of the catalyst within a pressure range from 0.1 to 2 MPa, v) treatment of the catalyst over a period of 0.1 to 24 h, vi) treatment of the catalyst with a specific catalyst hourly space velocity of 0.1 to 100 h?1.

Abstract: The invention relates to a method for producing isobutene by cracking MTBE, wherein the following steps are carried out: a) MTBE synthesis; reacting isobutene-containing hydrocarbon mixtures (II) with methanol (III), contained in one or more methanol-containing streams (VIII, IX), on acidic ion exchangers obtaining a stream (IV) containing MTBE and TBA, b) MTBE separation; separating a stream (V) containing MTBE and TBA from stream (IV) by means of distillation, c) MTBE cracking; cracking the stream (V) on a heterogenic catalyst in the gas phase, thus obtaining a stream (VI) which contains at least isobutene, methanol, MTBE, water, and optionally TBA, d) isobutene separation; separating the stream (VI) by means of distillation, thus obtaining a stream (VII) containing more than 50 mass % of the amounts of methanol, TBA, and water contained in stream (VI), and a stream (XVII) containing isobutene, e) water separation; separating, water from the stream (VII) to below 1 mass % by means of distillation, thus obta

Abstract: Process for telomerizing noncyclic olefins having at least two conjugated double bonds with at least one nucleophile using a catalyst containing a metal of group 8, 9 or 10 of the Periodic Table of the Elements, wherein the overall telomerization process has a process step of catalyst recycling, in which hydrogen is added via a hydrogen source to the mixture present in this process step.

Abstract: A process for preparing isobutene from MTBE-containing mixtures, including: a) in a reactor, cleaving a mixture obtained from an MTBE-containing feedstock and/or an MTBE-containing stream, affording a stream of reaction products including isobutene, methanol, MTBE, and by-products, which are a1) high boilers having a boiling range above 55° C. at a pressure of 0.1 MPa, a2) medium boilers having a boiling range of 12 to 55° C. at a pressure of 0.1 MPa, and a3) low boilers having a boiling range below 12° C. at a pressure of 0.1 MPa; b) distillatively separating stream into a stream which contains the isobutene product and low boilers, and a stream which contains MTBE, methanol, medium boilers and high boilers; c) distillatively separating stream to obtain an MTBE-containing stream and a methanol-containing high boiler stream; and d) recycling an MTBE-containing stream into a) of the process, the medium boilers being removed completely or partially before d) from the streams rich in medium boilers.

Abstract: The invention relates to a process for preparing 1-butene from technical mixtures which comprise at least 1-butene, isobutene, n-butane and 2-butenes by partial conversion of the isobutene present, distillative removal of a fraction comprising 1-butene and isobutene, and conversion of the isobutene present therein to tert-butyl ethers.

Abstract: The invention relates to a process for preparing metal complexes containing carbene ligands by reacting metal compounds with ligand precursors II and/or III and to the use of the thus obtained metal complexes as catalysts.