Abstract: Process for manufacturing .SIGMA.- caprolactone by oxidation of cyclohexanone by means of a crude C.sub.2 -C.sub.4 percarboxylic acid solution, resulting from the reaction of hydrogen peroxide on the corresponding carboxylic acid in the presence of a weak acid catalyst, with continuous elimination of water by azeotropic entrainment, characterized in that the molar ratio of cyclohexanone used to the percarboxylic acid is between about 0.50 to 0.99.

Abstract: This invention relates to a process for the preparation of stable solutions of .epsilon.-caprolactone by means of the oxidation of cyclohexanone by a percarboxylic acid containing 2 to 4 carbon atoms. According to the invention, the percarboxylic acid is in the form of a crude solution, such as that resulting from the reaction of hydrogen peroxide with the corresponding carboxylic acid in the presence of a boric acid catalyst with the continuous elimination of water by azeotropic entrainment.

Abstract: Process of preparing substantially anhydrous solutions of percarboxylic acids which comprises reacting hydrogen peroxide contained in an aqueous solution with a water miscible carboxylic acid in the presence of a catalyst and an azeotropic organic solvent, continuously removing the water added with the hydrogen peroxide and formed during the reaction by azeotropic distillation by way of a distillation column, and continuously injecting water into the top of the distillation column during at least the major portion of the reaction time, the quantity of the injected water being less than the quantity of the water removed by azeotrope distillation.

Abstract: Processes for treating the waste water, particularly waste water containing certain unsaturated compounds, from acrolein and acrylic acid production plants to reduce the chemical oxygen demand (COD), which processes comprise polymerizing the unsaturated compounds, desirably with peroxygen compounds; neutralizing the waste water with a reagent forming polyvalent metal ions to provide salts of the polymerized compounds; and separating the salts so formed.