REGENERATION OF ION EXCHANGE RESIN

PURPOSE:To enhance regeneration efficiency, in the regeneration of a basic anion exchange resin used in the purification of methacrylic acid, by substituting a resin bed with an org. solvent for extracting methacrylic acid and subsequently substituting the same with a hydrophilic solvent to wash the resin. CONSTITUTION:A methacrylic acid-containing extractant held at predetermined temp. is allowed to pass through a column packed with a basic anion exchange resin at a constant flow speed to obtain methacrylic acid containing no maleic acid and citraconic acid of a limit of detection. When the anion exchange resin reaches a breakpoint, the passage of the extractant is stopped and the residual liquid in the column is washed an substituted with an org. solvent for extracting methacrylic acid and subsequently substituted and washed with a hydrophilic solvent such as acetone or methanol and further sufficiently washed with water. Thereafter, when alkali regeneration treatment is performed using an about 5wt% aqueous caustic soda solution, the alkali regeneration efficiency of the anion exchange resin is markedly enhanced.