Abstract: Provided is an apparatus for preparing silanes of the general formula HnSiCU n where n=1, 2, 3 and/or 4 by dismutation of a chlorinated silane in the presence of a catalyst, wherein the apparatus includes: a distillation column having a column bottom, a column top, at least one feed inlet, a plurality of product offtakes, and a chimney tray; and a side reactor containing a catalyst bed having an upper edge, the side reactor being connected to the distillation column via at least three pipes including a first pipe, a second pipe, and a third pipe.

Abstract: The invention relates to a device and a method for producing mono-, oligo- and/or polyborosilazanes that contain carbon. According to said method (i) a one-component precursor compound is reacted with ammonia or an organic amino in an aminolysis step, (ii) a reaction mixture is extracted at least once from the aminolysis in a continuous extraction step using an organic solvent, (iii) ammonia or a phase containing organoamine that accumulates during the extraction process is discarded, recovered or at least partly recirculated and (iv) mono-, oligo- and/or polyborosilazanes containing carbon are obtained from the extraction phase containing the solvent.

Abstract: The invention relates to an apparatus, for preparing silanes of the general formula HnSiCl4-n where n=1, 2, 3 and/or 4 by dismutation of at least one relatively highly chlorinated silane in the presence of a catalyst, which is based on at least one distillation column (1) having a column bottom (1.1) and a column top (1.2), at least one side reactor (2) with catalyst bed (3), at least one feed inlet (1.3), a product offtake (1.4) and at least one further product offtake (1.5 or 1.8), where the distillation column (1) is provided with at least one chimney tray (4) and at least one side reactor (2) is connected to the distillation column (1) via at least three pipes (5, 6, 7) in such a way that the connection point of the line (5) to the distillation column (1) for the discharge of the condensate from the chimney tray (4, 4.1) is at a higher level than the upper edge of the catalyst bed (3, 3.1 or 3.2), the line (6) for the discharge of the liquid phase from the side reactor (2) opens (6.

Abstract: Hydrogen chloride gas contaminated with foreign hydrogen halides may be purified by a process comprising selectively absorbing the foreign hydrogen halide in an absorption medium, preferably water or an aqueous hydrogen chloride solution. To minimize the mass flow of the foreign hydrogen halide loaded absorption medium which is discharged from the process, the absorption medium is preferably conveyed countercurrent to the gas in at least two coupled circuits in the absorber.

Abstract: Hydrogen halides in the gas phase are separated by a process, comprising contacting a gas comprising at least two hydrogen halides with an adsorbent, whereby the adsorbent selectively adsorbs and retains at least one of the hydrogen halides.

Abstract: A process for the removal of ethers and/or PAH's from water, such as contaminated groundwater, is provided that proceeds by initially separating off solid constituents and then adsorbing ethers and polycyclic aromatic hydrocarbons to an adsorber resin, then, as needed, desorbing the adsorbed compounds with steam and regenerating the adsorber resin with an acid, to provide purification of highly polluted groundwater to such a substantial extent that the groundwater can be added to flowing surface waters without problem, and, if desired, used as cooling water or, after further biological purification, as drinking water.

Abstract: Conventional regenerative adsorptive methods for the purification of waters of organic constituents are limited in their application, when owing to a low content of organic water constituents the loading of the adsorbers is so low that the condensed water vapor desorbate no longer has a tendency to form two phases, or when the organic components are readily water-soluble and thus, following desorption with water vapor, can be separated only with difficulty out of the condensed desorbate. The process of the invention improves the tendency toward phase separation by cycling back the aqueous phase of the desorbate onto a loaded adsorber prior to its desorption in order to increase the loading and reduce, through additional supply of external heat, the required amount of water vapor for desorption. The present process is particularly useful for purification of industrial process waters or ground water.

Abstract: Polluted groundwater is purified by separating off solids and adsorbing dissolved organic compounds to an adsorber resin. The adsorbed organic compounds are desorbed using steam and the adsorber resin is regenerated using an acid and an oxygen-containing gas. The process makes it possible to separate aromatic and halogenated hydrocarbons off of heavily polluted groundwater to the extent that the groundwater can be added to flowing surface water without reservation. The purified water can, if appropriate, be used as cooling water, or after further biological purification, as drinking water.

Abstract: C.sub.8-18 alkylpolyglycosides are prepared by reacting a C.sub.1-6 alkyl glycoside with a C.sub.8-18 alcohol in a reaction column.

Abstract: Alkyl glycosides and alkyl oligoglycosides of low iodine color number can be preparedby acid-catalyzed condensation of saccharides in an aqueous solution with short-chain alcohols at elevated temperature in a counter-current reaction column.

Abstract: Alcohols and acids are esterified by means of liquid-phase equilibrium reactions on ion exchangers in an apparatus comprising a prereactor and a rectifying column with external reactors. The process is characterized by the fact that a portion of one of the starting compounds is fed directly to the external reactors.