Abstract: An electrolyte solution for a lithium secondary battery comprises a nonaqueous solvent and a fluorine-containing electrolyte capable of dissociating into lithium ions, wherein the content of HF in the electrolyte solution is less than 30 ppm.

Abstract: A process for preparing a high purity H.sub.2 O.sub.2 aqueous solution, which comprises the steps of: (a) feeding a crude H.sub.2 O.sub.2 aqueous solution containing H.sub.2 O.sub.2, organic carbon impurities and inorganic impurities into a distillation column having an inner wall at least the surface of which is made of a fluorine resin and internals and packings at least the surface of which are made of a fluorine resin being provided internally of the distillation column, from a bottom portion of the distillation column; (b) subjecting the crude hydrogen peroxide aqueous solution to distillation under reduced pressure and under heating the bottom portion; (c) taking out a distillate containing an extremely low concentration of H.sub.2 O.sub.

Abstract: This invention relates to a process for purifying a hydrogen peroxide aqueous solution, which comprises bringing a high concentration hydrogen peroxide aqueous solution containing a large amount of phosphoric acid obtained by extracting with water a reaction mixture prepared by a method of forming hydrogen peroxide by an oxidation-reduction process of anthraquinones, into contact with specific active alumina particles at a temperature of 0.degree. to 50.degree. C. for 6 to 500 minutes to remove a phosphoric acid component from the above high concentration hydrogen peroxide aqueous solution at a high rate substantially without causing decomposition of hydrogen peroxide.

Abstract: Disclosed is a process for preparing .epsilon.-caprolactone comprising using a percarboxylic acid solution obtained by oxidizing organic carboxylic acid in an organic solvent in the presence of hydrogen peroxide and a boric acid catalyst, and cyclohexanone, supplying 1 to 1.5 mole of percarboxylic acid, 0.012 mole or less of hydrogen peroxide and 0.04 mole or less of the boric acid catalyst per mole of cyclohexanone in a reaction system, and reacting said cyclohexanone with said percarboxylic acid to form .epsilon.-caprolactone.

Abstract: A process for preparing perpropionic acid solution comprising reacting propionic acid with hydrogen peroxide in the presence of a boric acid catalyst wherein the reaction is carried out by using an ethyl propionate as a reaction solvent, and water in the reaction solution is removed continuously by azeotropic distillation with the reaction solvent. Since the reaction is carried out while the concentration of the peroxide in an aqueous phase separated from the distillate by the azeotropic distillation is maintained at not more than 0.1% by weight, a perpropionic acid solution containing almost no unreacted hydrogen peroxide can be prepared.