Abstract: A process for the preparation of a color stable C6-12 saturated aliphatic carboxylic acid in which (1) the corresponding aldehyde is oxidized with molecular oxygen to obtain the crude saturated aliphatic carboxylic acid in a liquid mixture, (2) molecular oxygen removed from the crude saturated aliphatic carboxylic acid mixture, and (3) the saturated aliphatic carboxylic acid separated from the molecular oxygen depleted mixture by distillation as a color stable product.

Abstract: The invention relates to crystals (C) consisting of at least 98% by weight of 4,4?-dichlorodiphenylsulfone, 0 to 2% by weight of impurities and 0 to 2% by weight of at least one solvent (c). Moreover, the present invention relates to a crystal composition (CC) comprising crystals (C) and a process for the production of the crystal composition (CC) and the crystals (C).

Abstract: The invention relates to a process for purifying crude 4,4?-dichlorodiphenyl sulfone comprising: (a) dissolving the crude 4,4?-dichlorodiphenyl sulfone which may contain water in an organic solvent in which 4,4?-dichlorodiphenyl sulfone has a solubility of 0.5 to 20% at 20° C. and optionally adding water to obtain a solution which comprises 4,4?-dichlorodiphenyl sulfone, the organic solvent and 1 to 30 wt % water based on the amount of 4,4?-dichlorodiphenyl sulfone and water; (b) cooling the solution to a temperature below the saturation point of 4,4?-dichlorodiphenyl sulfone to obtain a suspension comprising crystallized 4,4?-dichlorodiphenyl sulfone; (c) carrying out a solid-liquid separation to obtain residual moisture containing 4,4?-dichlorodiphenyl sulfone and a mother liquor; (d) washing the residual moisture containing 4,4?-dichlorodiphenyl sulfone with an organic solvent in which 4,4?-dichlorodiphenyl sulfone has a solubility of 0.5 to 20% at 20° C.

Abstract: The invention relates to a process for purifying 4,4?-dichlorodiphenyl sulfone comprising: (a) providing a suspension comprising particulate 4,4?-dichlorodiphenyl sulfone in carboxylic acid, (b) carrying out a solid-liquid separation of the suspension to obtain residual moisture containing 4,4?-dichlorodiphenyl sulfone and a carboxylic acid comprising filtrate, (c) washing the residual moisture containing 4,4?-dichlorodiphenyl sulfone with an aqueous base and then with water, (d) mixing the aqueous base after being used for washing with a strong acid, or mixing the aqueous base after being used for washing, the carboxylic acid comprising filtrate and a strong acid, (e) carrying out a phase separation in which an aqueous phase and an organic phase comprising the carboxylic acid are obtained.

Abstract: The invention relates to a process for producing 4,4?-dichlorodiphenyl sulfone, comprising: (a) reacting 4,4?-dichlorodiphenyl sulfoxide and an oxidizing agent in at least one carboxylic acid as solvent to obtain a reaction mixture comprising 4,4?-dichlorodiphenyl sulfone and carboxylic acid; (b) separating the reaction mixture into a first stream comprising 4,4?-dichlorodiphenyl sulfone and a second stream comprising carboxylic acid; (c) purifying the second stream comprising carboxylic acid by distilling a part of the second stream comprising carboxylic acid stripping low boilers from at least a part of the second stream comprising carboxylic acid (d) recycling the purified carboxylic acid into the reaction (a).

Abstract: The invention relates to a process for producing 4,4?-dichlorodiphenyl sulfone, comprising: (I) reacting thionyl chloride, chlorobenzene and aluminum chloride forming an intermediate reaction product and hydrogen chloride; (II) mixing aqueous hydrochloric acid and the intermediate reaction product to obtain an organic phase comprising 4,4?-dichlorodiphenyl sulfoxide and an aqueous phase; (III) cooling the organic phase to a temperature below the saturation point of 4,4?-dichlorodiphenyl sulfoxide to obtain a suspension; (IV) solid-liquid-separation of the suspension to obtain crystallized 4,4?-dichlorodiphenyl sulfoxide, and mother liquor; (V) washing the crystallized 4,4?-dichlorodiphenyl sulfoxide with a carboxylic acid to obtain carboxylic acid-wet 4,4?-dichlorodiphenyl sulfoxide; (VI) reacting the washed 4,4?-dichlorodiphenyl sulfoxide and an oxidizing agent in a carboxylic acid as solvent to obtain a reaction mixture comprising 4,4?-dichlorodiphenyl sulfone and carboxylic acid; (VII) separating the react

Abstract: A process for preparing polyaryl ethers in which a polycondensation of the monomer building blocks is carried out using microwave irradiation leads to thermoplastic molding compositions having improved color properties.

Abstract: A process for preparing polyaryl ethers in which a polycondensation of the monomer building blocks is carried out using microwave irradiation leads to thermoplastic molding compositions having improved color properties.

Abstract: A process for preparing polyaryl ethers in which a polycondensation of the monomer building blocks is carried out using microwave irradiation leads to thermoplastic molding compositions having improved color properties.

Abstract: The present invention relates to a novel method for purifying cyclohexadec-8-en-1-one, a method for preparing cyclohexadec-8-en-1-one and cyclopentadecenones, the substances and substance mixtures prepared therefrom and use thereof as aroma substances, particularly as fragrances, and also aroma substance compositions and agents comprising these mixtures.

Abstract: The present invention relates to new types of cyclic carbaldehydes, the preparation thereof and the use as aromachemical, in particular as fragrance, and to aroma substance compositions and products comprising these carbaldehydes.

Abstract: The present invention relates to novel mixtures of cyclopentadecenone isomers, preparation thereof and use thereof as aroma substances, particularly as fragrances, and also aroma substance compositions and agents comprising said mixtures.

Abstract: The present invention relates to the use of hexadeca-8,15-dienal or of a substance mixture which comprises this compound as aroma chemical, in particular as fragrance, or formulation auxiliary; and also to processes for its preparation, moreover aroma substance compositions and compositions comprising hexadeca-8,15-dienal.

Abstract: The present invention relates to new types of cyclic carbaldehydes, the preparation thereof and the use as aromachemical, in particular as fragrance, and to aroma substance compositions and products comprising these carbaldehydes.

Abstract: The present invention relates to the use of hexadeca-8,15-dienal or of a substance mixture which comprises this compound as aroma chemical, in particular as fragrance, or formulation auxiliary; and also to processes for its preparation, moreover aroma substance compositions and compositions comprising hexadeca-8,15-dienal.

Abstract: A process for preparing trisaziridinomethane (I) by reacting aziridine with chloroform, wherein the molar ratio of aziridine to chloroform is not more than 3:1.