Method for the purification of acrylamido-2-methyl-2-propanesulphonic acid

Abstract

The invention relates to a method for the purification of acrylamido-2-methyl-2-propanesulphonic acid comprising the following successive steps: 1) preparation of a suspension of acrylamido-2-methyl-2-propanesulphonic acid crystals by distillation of an aqueous solution of acrylamido-2-methyl-2-propanesulphonic acid in order to obtain a suspension of acrylamido-2-methyl-2-propanesulphonic acid crystals, 2) isolation of the acrylamido-2-methyl-2-propanesulphonic acid crystals generally by solid/liquid separation from said suspension in order to isolate said acrylamido-2-methyl-2-propanesulphonic acid crystals, characterised in that the distillation step is carried out continuously and at a pressure below atmospheric pressure. The invention also relates to a polymer obtained from acrylamido-2-methyl-2-propanesulphonic acid crystals or its salts, obtained according to such a method, and to the use of said polymer in oil and gas recovery, in water treatment, in sludge treatment, in manufacturing paper, in construction, in mining, in cosmetic formulation, in detergent formulation, in textile making, or in agriculture.

Dependencies are inferred from the claim text.