Abstract: An aqueous solution of acrylamide obtained by catalytic hydration of acrylonitrile in the presence of a copper-based catalyst is purified by the steps, in sequence, of (a) removal of the unreacted acrylonitrile, (b) removal of copper, (c) treatment under basic conditions, (d) cation exchanging treatment and (e) weakly basic anion exchanging treatment. The acrylamide obtained by this process has good storage stability. An acrylamide polymer produced from this monomer is useful as a flocculant having a reduced content of the unreacted monomer, a high molecular weight and excellent solubility in water.

Abstract: An improved process is disclosed for the purification of an aqueous solution of acrylamide. It comprises bringing a crude aqueous solution of acrylamide into contact with oxygen or an oxygen-containing gas and thereafter subjecting the solution to a dual treatment with a strongly acidic cation exchange resin followed by a weakly basic anion exchange resin. If necessary, the aqueous solution of acrylamide is treated, while maintaining its oxygen content at least at 4ppm and then subjected to the treatment with the ion exchange resins.