Abstract: A process for preparing ethyl tert-butyl ether (ETBE) using low-water ethanol obtained by membrane dewatering at least two streams of relatively water-rich ethanol that have a different water content. by dewatering at membranes.

Abstract: A process for preparing low-water ethanol from at least two streams of relatively water-rich ethanol that have a different water content by dewatering at membranes. The low-water ethanol can be used to prepare ethyl tert-butyl ether (ETBE).

Abstract: The invention relates to a process for preparing 1-butenic fractions having less than 2000 ppm of isobutene in relation to 1-butene from technical mixtures of C4 hydrocarbons I which contain at least 1-butene and 2000 ppmw to 8% by mass of isobutene based on the 1-butene, with or without n-butane, isobutane and/or 2-butenes.

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: A process for preparing low-water ethanol from at least two streams of relatively water-rich ethanol that have a different water content by dewatering at membranes. The low-water ethanol can be used to prepare ethyl tert-butyl ether (ETBE).

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 the oligomerization of butenes, in which a stream which contains predominantly butenes and has been obtained by separation from a stream of hydrocarbons having a lower content of butenes, scrubbing and drying is fed to the oligomerization.

Abstract: The invention relates to a process by which C4- to C6-olefins or an essentially sulfur-free olefin cut comprising C4- to C6-olefins is isomerized over a catalyst comprising an element of the eighth transition group of the Periodic Table, in the presence of at least one added sulfur compound, and any polyunsaturated hydrocarbons contained therein are selectively hydrogenated and hydroisomerized, and also the sulfur compounds are separated from the product and optionally recycled, so that virtually sulfur-free products are obtained.

Abstract: The present invention provides a process, which includes: contacting at least one C4-hydrocarbon stream which includes isobutene with methanol over at least one acid catalyst and preparing methyl tert-butyl ether (MTBE) and a substantially isobutene-free C4-hydrocarbon mixture; wherein in a first stage in one or more first reactors, the isobutene reacts with the methanol over an acid catalyst to form an equilibrium mixture which includes MTBE, remaining isobutene and methanol; the equilibrium mixture is fed to a second stage which includes a reactive distillation column; and in the reactive distillation column, the remaining isobutene reacts with methanol over an acid ion exchange resin to form MTBE; wherein the reactive distillation column is operated at a pressure ranging from 3 to 15 bar abs., a reaction zone temperature ranging from 55° C. to 75° C., and a reflux ratio of less than 1.

Abstract: The present invention provides a process, which includes: