Abstract: The present invention relates to a process for preparing quaternary phosphonium salts by reacting a ternary phosphine with an optionally substituted, saturated or monounsaturated or polyunsaturated electrophile having from 3 to 25 carbon atoms in ternary solvent mixtures.

Abstract: The present invention relates to a process for preparing vitamin A acetate by reacting ?-vinylionol with triphenylphosphine in the presence of sulfuric acid in a solvent mixture consisting of 60 to 80% by weight methanol, 10 to 20% by weight water and 10 to 20% by weight aliphatic, cyclic or aromatic hydrocarbons having 5 to 8 carbon atoms to give ?-ionylideneethyltriphenylphosphonium salts and subsequent Wittig reaction with 4-acetoxy-2-methylbut-2-enal.

Abstract: A process for postcrosslinking a water-absorbing polymer comprises said polymer being treated with a postcrosslinker and, during or after said treating, being postcrosslinked and dried by temperature elevation, said postcrosslinker being a compound of the formula I where R1, R2, R3, R4, R5, R6, R7, R8 and R9 are each independently hydrogen, C1-C12-alkyl, C2-C12-alkenyl or C6-C12-aryl, wherein C1-C12-alkyl, C2-C12-alkenyl or C6-C12-aryl may be halogen substituted. The liquid-absorbing polymers are useful in hygiene articles and packaging materials.

Abstract: The invention relates to the reduction of the content of MEHQ (methoxyhydroquinone) of acrylic acid or its salts by means of continuous adsorption on activated carbon. In particular, MEHQ is removed from partly or fully neutralized acrylic acid.

Abstract: Disclosed is a method for jointly producing (i) formic acid (III); (ii) a carboxylic acid comprising at least two carbon atoms (II) and/or the derivatives thereof; and (iii) a carboxylic acid anhydride (VII). According to said method, (a) a formic acid ester (I) is transesterfied to formic acid (III) and the corresponding carboxylic acid ester (IV) by means of a carboxylic acid comprising at least two carbon atoms (II); (b) at least one portion of the carboxylic acid ester (IV) formed in step (a) is carbonylated in order to obtain the carboxylic acid anhydride (V); and (c) at least one portion of the carboxylic acid anhydride (V) formed in step (b) is further dehydrated by means of a carboxylic acid (VI) so as to form a carboxylic acid anhydride (VII) and the carboxylic acid (II).