Process for purifying acrylamides
AssigneeNitto Kagaku Kogyo Kabushiki Kaisha
InventorsIwao Ohshima, Seiichi Chiba, Kenzo Ariyama, Yasuo Ogawa, Masahide Ozaki
Life of this patent
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Abstract
Process for purifying an acrylamide including the steps of (1) adding an inorganic base (excluding ammonia) to an aqueous solution containing 15 to 60% by weight of the acrylamide at a temperature of up to 60.degree.C in an amount of 0.1 to 1.5 wt. % based on the acrylamide and (2) blowing a gas, inert to the acrylamide, into the resulting mixture at a hydrogen ion concentration of a pH of 12 to 13.7 and if necessary, (3) subjecting the so treated acrylamide solution to an active carbon adsorption treatment.
Claims15
A process for purifying an acrylamide containing cross-linking impurities which comprises adding an inorganic base (excluding ammonia) to an aqueous solution containing 15 to 60% by weight of the acrylamide at a temperature of up to 60.degree.C, in a quantity of 0.1 to 1.5% based on the acrylamide;
- and blowing a gas inert to the acrylamide into the resulting mixture at a hydrogen ion concentration of pH of 12 to 13.7 thereby carrying off, by the gas, ammonia which is a hydrolysis product of said cross-linking impurities from the aqueous solution in which the acrylamide remains substantially intact.
A process for purifying an acrylamide containing cross-linking impurities which comprises adding an inorganic base (excluding ammonia) to an aqueous solution containing 15 to 60% by weight of the acrylamide at a temperature of up to 60.degree.C, in a quantity of 0.1 to 1.5% based on the acrylamide, blowing a gas inert to the acrylamide into the resulting mixture at a hydrogen ion concentration of pH of 12 to 13.7 thereby carrying off by the gas, ammonia which is a hydrolysis product of said cross-linking impurities from the aqueous solution in which the acrylamide remain substantially intact, and subjecting the acrylamide solution, thus treated, to an activated carbon absorption treatment.
Dependencies are inferred from the claim text.