A method for the production of high-purity 2 - acrylamido - 2 - methylpropane

摘要

PURPOSE:Acrylonitrile, fuming sulfuric acid, and isobutene are made to react to form a slurry, to which acetic acid is added to substitute the solvent, then, the product is recrystallized from water to produce high-purity title compound that can be used to form high-molecular-weight polymers. CONSTITUTION:To a slurry containing crystals of 2-acrylamide-2-methylpropanesulfonic acid (AMPS) resulting from the reaction between acrylonitrile, furming sulfuric acid, and isobutene is added acetic acid double the volume of the reaction solvent, then the reaction solvent is distilled off. Then, to the resulting slurry of the reaction mixture is added water in an amount necessary for dissolving completely AMPS crystals at 60-100 deg.C, (preferably forming 10% water-containing acetic acid) and the crystals are dissolved completely, then cooled immediately. The AMPS crystallizing out is centrifugally separated from the liquid. EFFECT:The reaction and purification can be carried out in the same equipment and the separation, rinsing and drying of the crystals can be sufficiently effected by only once operation respectively.