Abstract: Tertiary alcohols can be prepared by the hydration of tertiary olefins having the same number of carbon atoms on an acidic ion exchanger using special structured multi-purpose packings for heterogeneous reactive rectification. An excellent yield and purity of the alcohol and an extended service life of the catalyst are achieved.

Abstract: Cyclopentane and/or cyclopentene and, if desired, isopentane can be obtained by distillative separation from a pre-benzene fraction or a C5 fraction which has in each case being partially hydrogenated to remove acetylene compounds and diolefins, wherein a) in a first fractional distillation, low boilers are removed as first top product and, either b1) the first bottom product is fed to a second fractional distillation and there cyclopentene is taken off as second top product and cyclopentane and higher-boiling hydrocarbons are taken off as second bottom product and this second bottom product is separated into cyclopentene and higher boilers in a third fractional distillation, or b2) the first bottom product is subjected to a catalytic hydrogenation and subsequently, in a fractional distillation, separated into cyclopentane as top product and higher boilers as bottom product, or b3) the first bottom product is subjected to a fractional distillation to separate off the relatively high boilers as bottom prod

Abstract: The production of 1,2-butadiene in purities of at least 85% becomes possible by means of a process in which a polymerization-inhibitor-containing C4 hydrocarbon fraction is subjected to at least one fractional distillation.

Abstract: The present invention relates to silver-containing and optionally promoter-containing supported catalysts and catalyst intermediates, processes for their preparation and their use for preparing alkylene oxides by oxidation of alkenes with oxygen. The catalysts are prepared by treatment of a support with a lactic acid containing silver ions, nitrate ions and optionally promoter metal ions, drying, predecomposition in a virtually oxygen-free atmosphere and subsequent activation by heating in an oxygen-containing atmosphere while precisely controlling the temperature conditions and the feeding-in of oxygen. The catalyst intermediates obtainable by treatment, drying and only predecomposition can be activated in a temporally and physically separate process step to form the actual catalysts. Suitable promoters are alkaline earth metal compounds and/or alkali metal compounds. High activities and high selectivities are achieved when using the catalysts of the invention for preparing alkylene oxides.

Abstract: A catalytic agent for etherifying, hydrogenating and isomerizing crude C.sub.4 -C.sub.8 -- hydrocarbon mixtures having a sulfur content, comprising a macroporous or gel cation exchanger having SO.sub.3 H groups and being charged with a mixture of a metal selected from the group consisting of Pd, Ru, Rh and Pt with a metal selected from the group consisting of Fe, Co, Ni, Cu, Ag and W.

Abstract: C.sub.4 -C.sub.6 -alkenes having an internal double bond can be produced by hydroisomerization of C.sub.4 -C.sub.6 -alkenes having a terminal double bond in the presence of H.sub.2 on a catalyst having a content of a noble metal of group VIII of the Periodic Table of the Elements (Mendeleev), if C.sub.4 -C.sub.6 -alkenes having a terminal double bond are fed into a hydroisomerization reactor after preheating, as such or in a mixture with other hydrocarbons, and the reaction product is divided into a work-up stream and a recycle stream. The recycle stream is recycled to the inlet of the hydroisomerization reactor and is used there as feed together with the C.sub.4 -C.sub.6 -alkenes having a terminal double bond or with the hydrocarbon stream comprising the C.sub.4 -C.sub.6 -alkenes having a terminal double bond and with the H.sub.2.

Abstract: The i-butene present in a C.sub.4 raffinate I is subjected in a first step to a first hydroisomerization. The hydroisomerization product is subjected to fractional distillation, with essentially 2-butene and n-butane being obtained as bottom product and i-butene and i-butane being obtained as overhead product. The overhead product is condensed and the condensate is divided into two parts. One part is subjected to a second hydroisomerization and the second hydroisomerate is recycled to the upper third of the fractionation column. The other part of the condensed overhead product is fed to the oligomerization. The condensed overhead-product of the fractionation column is divided in such a manner that, based on 1 part by volume of condensate conducted to the oligomerization, 1-5 parts by volume are fed to the second hydroisomerization.

Abstract: Molybdenum/bismuth-based fluid-bed catalysts which are used for the ammoxidation of olefins can be reactivated by addition of a mixed oxide of formulaMo.sub.20 (P, Cr).sub.0.3-2.0 (Bi, Ni, Fe, Co).sub.1.33-4.0 O.sub.xwherein, besides Mo, one element from component group (P, Cr) and one or more metals from component group (Bi, Ni, Fe, Co) are present, andx results from the valency requirements,the mixed oxide being applied to SiO.sub.2 as support.

Abstract: High-octane, low-olefin motor fuels and motor fuel components having a content of alkyl tert.-alkyl ethers can be produced by reacting a crude hydrocarbon stream, which contains tertiary C.sub.5 -C.sub.8 -olefins in addition to saturated and olefinically, diolefinically and acetylenically unsaturated hydrocarbons in the same boiling range, simultaneously with one or more C.sub.1 -C.sub.4 -alkanols in a quantity from 0.5 to 5 mol per mol of the tertiary olefin(s) and with excess hydrogen relative to the total unsaturation under a pressure from 12 to 80 bar and at a temperature from 60.degree. to 180.degree. C. on a catalyst known per se or a mixture of catalysts known per se, which effect(s) both the etherification and the olefin hydrogenation.

Abstract: The ammonium sulphate contained in tar-rich waste streams from the production of (meth)acrylonitrile can be precipitated out by adding 1 to 30 times the amount by weight of methanol, relative to the water content of the waste stream, and additionally 0.05 to 10% the amount by weight of ammonia, relative to methanol, to such a waste stream at 10.degree.-60.degree. C. and separating off the ammonium sulphate which precipitates out. The waste stream remaining after separating off the ammonium sulphate can, for example, be disposed of as low-sulphur waste-fuel in a combustion chamber.

Abstract: Alkyl tert.-alkyl ethers can be cleaved into the underlying alkanols and tert.-olefins in the presence of strongly acidic substances in a column apparatus, the strongly acidic substance being made available at the foot of the column. A particularly advantageous process design results when a water stream is fed below the top column tray in countercurrent to the tert.-olefin flowing upwards and is taken off again from the column above the bottom circulation; in the case of using an insoluble, strongly acidic substance, the latter is located in a catalyst bed at the foot of the column, and the alkyl tert.-alkyl ether is preferably fed in between the catalyst bed and the bottom circulation evaporator.

Abstract: The effluent arising in the production of acrylonitrile can be purified by adjusting it to a pH value from 4 to 9 and then subjecting it to reverse osmosis at a membrane at a temperature from 10.degree. to 50.degree. C. and a differential pressure of 10 to 80 bar. The flow velocity at the membrane is adjusted to a value from 0.5 to 4 m/second. The concentrate is recycled into the acrylonitrile production process.

Abstract: Alkenes having a terminal double bond can be isomerized to give alkenes having an internal double bond if alkenes having a terminal double bond or hydrocarbon feedstock having a content of alkenes of this type having a terminal double bond are subjected to treatment, in the presence of hydrogen, over a macroporous or gel-like cation exchanger in the H.sup.+ form which contains 0.001 to 10 g of one or more metals of the VIth and/or VIIth and/or VIIIth sub-group of the periodic system of the elements in elementary form per liter of dry cation exchanger and which has a degree of crosslinking of 2 to 65% and a specific surface area of 5 to 750 m.sup.2 /g of dry exchange resin. The treatment is carried out in the liquid phase at a temperature from 0.degree. to 120.degree. C.

Abstract: Tert.-Amyl alcohol (TAA) can be prepared in an advantageous manner by hydrating of i-amylenes on an acid cation exchanger by carrying out the reaction in the vicinity of the boiling point of the i-amylenes under the appropriate reaction pressure. A higher content of TAA is thereby obtained in the reaction mixture.

Abstract: Olefinic hydrocarbons present in mixtures containing tert.-alkyl alkyl ethers and, if appropriate, other saturated aliphatic or aromatic hydrocarbons can be hydrogenated with substantial preservation of the ethers if the catalyst used has an active component for hydrogenation on a catalyst support having a specific surface area of more than 50 m.sup.2 /g and a pore diameter of, in the main, <1,000 nm.

Abstract: A paint resin for powder coating is described which consists of modified high-pressure polyethylene (LDPE) and is characterized by(a) a content from 0.1 to 1 mol %, based on the total number of moles of all monomers, of unsaturated carboxylic acids present as copolymerized units, and/or the equivalent content of carboxylic anhydrides,(b) a neutralization degree of the carboxyl groups, which can also originate from anhydride groups, from 0 to less than 50%,(c) a termonomer content from 0 to 5 mol %, based on the total number of moles of all monomers,(d) a melt flow index from 20 to 200 g/10 minutes (190.degree. C.; 2.16 kp) and(e) a particle size from 1 to 600 .mu.m,as well as the use thereof in a process for powder coating.

Abstract: The invention relates to a device for feeding gases, aerosols and/or mixtures of gases and solids into the combustion of a steam boiler or other combustion chambers using heat, and a process for diminishing pollutants, which are formed when burning gases, aerosols and/or mixtures of gases and solids in steam boilers or other combustion chambers using heat.

Abstract: Crosslinked organic resins, containing SiO.sub.2 and sulphonic acid groups, having an SiO.sub.2 content of 0.1-10% by weight, relative to the total weight of the SiO.sub.2 -containing resins, are prepared by steeping crosslinked organic resins, containing sulphonic acid groups, in the alkali form in aqueous alkali metal silicate solutions or (quaternary) alkylammonium silicate solutions, and subsequently precipitating the SiO.sub.2 using mineral acid, and simultaneously converting the resin into the H.sup.+ form. These resins can be used as acid catalysts in the cleavage of tert.-alkyl ethers into the basic tertiary olefins and the basic alkanols. This use has proven particularly advantageous when the tert.-alkyl alkyl ethers to be cleaved are employed together with water for the cleavage.

Abstract: Tertiary olefins are obtained in pure form by cleavage of the pertinent tert.alkyl ethers with simultaneous formation of the pertinent alcohols on strongly acidic cation exchangers in the H.sup.+ form. This cleavage is carried out at elevated temperature and atmospheric to superatmospheric pressure. The process is carried out in such a fashion that the ether to be cleaved is employed as a mixture with water. The water may be employed in an amount from 2-50% by weight, relative to the amount of the ether to be cleaved. Suitable ethers to be cleaved are those based on tertiary C.sub.4 -C.sub.7 -olefins and primary C.sub.1 -C.sub.4 -alkanols.

Abstract: A device for emission-free sampling of volatile liquids comprises a 4-way tap from which lead two lines, which can be connected together, from and to the container holding the liquid to be tested and two other lines, which can also be connected together, lead to a sample bottle which can be sealed and which can be connected to the device. The device further comprises a supply line for an inert flushing medium, which joins the line leading into the sample bottle in the region of the sample bottle, and a discharge line for the inert flushing medium, which leads from the line coming out of the sample bottle in the region of the sample bottle and proceeds to a disposal system.