Abstract: A reflection column which contains liquid distributors having at least 500 drip points/m2, which are arranged at an angle of about 90° C. to cloth layers of packing elements located immediately therebelow; and a combination of insulation and protective heating. The column is advantageously used for the rectification of mixtures of high-boiling air- or temperature-sensitive substances requiring effective separation efficiency.

Abstract: Process for isolating pure substances from of mixtures of high-boiling air- and/or temperature-sensitive substances which require a high separation efficiency, by rectification under medium vacuum in columns containing metal cloth packings with ordered structure using channel liquid distributors with 500 or more drip points/m.sup.2, which are arranged at an angle of 90.degree. to the cloth layers of the packing elements located immediately below the distributors, in which two or more of the packing elements underneath the liquid distributors have only a very small height, which ensure virtual exclusion of air and are designed so that no heat exchange through the column wall can take place during the rectification. The patent also relates to packed columns which can be used for this process and to the use of this process and these columns for the final purification of vitamin E acetate by distillation.

Abstract: Packing elements with a low pressure drop for mass transfer column internals of the internal diameter of the column and of a height of from 40 to 300 mm made of dimensionally stable layers, which have an ordered structure and are in mutual contact, of cloth material or cloth-like material with a specific surface area of from 100 to 2000 m.sup.2 /m.sup.3, whereina) the shaped layers of cloth material or cloth-like material, preferably made of metal cloth, which are in mutual contact are arranged so that they form a multiplicity of narrow flow channels, preferably virtually triangular, virtually rectangular or else virtually equilateral hexagonal flow channels, in which the angle of inclination of the serration of the individual cloth layers of the packing to the column axis is only 0 to 25.degree., preferably 3 to 14.degree.

Abstract: A process for preparing .alpha.-tocopherol or tocopheryl acetate by cyclocondensation of trimethylhydroquinone with phytol or isophytol in the presence of an acid catalyst and of a solvent and, where appropriate, subsequent acetylation, which comprises carrying out the cyclocondensation and, where appropriate, the subsequent acetylation in liquid or supercritical carbon dioxide as solvent.

Abstract: A process for preparing dl-.alpha.-tocopherol or dl-.alpha.-tocopheryl acetate by acid-catalyzed reaction of 2,3,5-trimethylhydroquinone (TMH) with phytol or isophytol in a solvent at elevated temperature, with or without subsequent esterification of the resulting tocopherol with acetic anhydride, entails the reaction being carried out in the presence of a mixture of ortho-boric acid and certain aliphatic di- or tricarboxylic acids, preferably in the presence of a mixture of ortho-boric acid and oxalic acid.

Abstract: Pulverulent products composed of a water-insoluble core substance and of a protective covering, are obtainable bydispersing the core substance in an aqueous solution of amylose or a starch with an amylose content of more than 40% by weight as film-forming polymer for the protective covering,spraying this dispersion using hydrophobic silica as auxiliary andsubsequently drying the sprayed particles.

Abstract: Palladium catalysts can be obtained by vapor depositing metallic palladium on a carrier, treating the palladium coating with a metallic inhibitor by vapor deposition, and heating the product at from 300.degree. to 800.degree. C., and can be used for the partial hydrogenation of triple bonds to olefinic double bonds.

Abstract: 2,3,5-Trimethyl-p-benzoquinone is prepared by oxidation of trimethylphenol with oxygen or an oxygen-containing gas in the presence of a catalyst containing a copper(II) halide in a two-phase reaction medium consisting of water and an aliphatic alcohol at elevated temperatures by a process in which the reaction is carried out in a mixture of water and a saturated aliphatic alcohol of 12 to 18 carbon atoms, having a flashpoint greater than 120.degree. C., such as 1-dodecanol, 1-tetradecanol, 1-hexadecanol or 1-octadecanol, in particular 1-dodecanol, and at from 60.degree. to 100.degree. C.Particularly good yields of TMQ are obtained if the reaction is carried out in the presence of a copper(II) halide, such as CuCl.sub.2 or CuBr.sub.2, and of an alkaline earth metal halide, in particular CaCl.sub.2 or MgCl.sub.2, or of an alkali metal halide, in particular LiCl or NaCl, as the catalyst system.

Abstract: A process for pulverizing substances which are sensitive to oxidation, in particular oily substances, by dispersing oil-soluble substances, e.g. vitamins, carotinoids, pharmaceutically active compounds or aromas, in an aqueous solution of a film-forming colloid, which constitutes the continuous phase of the dispersion, with the addition of one or more substances from the group comprising the mono-, di- and polysaccharides, atomizing the dispersion, in a spray tower, in the presence of a spraying assistant and collecting the resulting particles in a fluidized bed, wherein, as the spraying auxiliary, a hydrophobic silica or a metal salt of a higher fatty acid is introduced above the fluidized bed and distributed uniformly in the spraying space, at a temperature at which the colloid of the atomized particles has not yet solidified, and the assistant-laden particles, colloid material of which essentially has not yet gelatinized, is collected in a fluidized bed, and dried therein in a conventional manner.

Abstract: A process for treating residues which result from the Wittig synthesis of olefins and which consist principally of methanol, triphenylphosphine oxide, salts and organic by-products, by steam-stripping the volatile constituents, with partial condensation of the steam, and separating the resulting aqueous-organic mixture at 80.degree.-100.degree. C. into a saline aqueous phase and an organic phase containing principally triphenylphosphine oxide. Using this process provides a simple method of freeing, from triphenylphosphine oxide and other organic impurities, the effluent from syntheses which result in the formation of triphenylphosphine oxide, and thereby on the one hand substantially facilitates the purification of the effluent and on the other hand provides a simple method of recovering the triphenylphosphine oxide.

Abstract: In the manufacture of tocopherol (vitamin E) by reaction of isophytol with trimethylhydroquinone in the presence of zinc chloride and acid in a hydrocarbon solvent one of the starting compounds, isophytol, is pretreated with small amounts of ammonia or an amine.Tocopherol is obtained in higher yield and purity.

Abstract: Aqueous solutions of polyenyltriarylphosphonium salts are prepared from solutions of the corresponding polyenyltriarylphosphonium salts in organic solvents by driving off the solvent with steam, part of the steam being allowed to condense. Some of the said triarylphosphonium salts may be used directly as pesticides while others are used as intermediates for organic syntheses, especially in the carotinoid field.