METHOD OF RECOVERING SORBIC ACID Russian patent published in 1997 - IPC

FIELD: waste water purification. SUBSTANCE: invention relates to cleaning waste water from sorbic acid production with simultaneously recovering sorbing acid with minimum material consumption. Method includes sorption on anionites, regeneration of anionites, precipitation of sorbic acid by way of neutralizing regeneration solution with hydrochloric acid followed by purifying low-grade sorbic acid. Method is distinguished with that thermal ionite recovery of sorbic acid from waste water is performed before ionite purification. Thermal ionite filters are used whose regeneration is carried out at temperatures below 100 C with sorbic acid solution, its concentration corresponding to sorbic acid concentration in waste water and solution flowing in countercurrent direction to waste water flow direction. In this case, precipitation of sorbic acid from regeneration solution is promoted by cooling regeneration solution to 4-10 C. Sorbic acid separated, mother liquor is recycled into regeneration cycle. EFFECT: reduced acid and alkali consumption and also volume of waste water to be disposed. 2 cl, 1 dwg