Production of acrylamide

Claim 1

IN A CONTINUOUS PROCESS FOR RECOVERING MONOMERIC ACRYLAMIDE FROM ACRYLAMIDE SULFATE WHICH COMPRISES NEUTRALIZING ACRYLAMIDE SULFATE WITH AMMONIA IN AN AQUEOUS MEDIUM THEREBY PRECIPITATING AMMONIUM SULFATE GIVING AN AQUEOUS SLURRY COMPRISING DISSOLVED ACRYLAMIDE AND CRYSTALLINE AMMONIUM SULFATE; THE AMOUNT OF AMMONIA BEING SUCH AS TO NEUTRALIZE SUBSTANTIALLY OF ENTIRE SULFURIC ACID CONTENT OF SAID ACRYLAMINDE SULFATE, AND THE AMOUNT OF SAID ACRYLAMIDE SULFATE BEING SUCH AS TO PROVIDE AFTER NEUTRALIZATION AN AQUEOUS SLURRY SUBSTANTIALLY SATURATED WITH ACRYLAMIDE AT A TEMPERATURE OF AT LEAST 20* C.; MAINTAINING THE HYDROGEN ION CONCENTRATION DURING NEUTRALIZATION AT A RANGE EQUIVALENT TO A PH OF ABOUT 2 TO ABOUT 7; SEPARATING PRECIPITATED AMMONIUM SULFATE AT A TEMPERATURE OF AT LEAST 20* C.; AND TREATING RESIDUAL LIQUOR TO RECOVER IN ACRYLAMIDE PRODUCT, THE IMPROVEMENT IN COMBINATION THEREWITH WHICH COMPRISES; PRIOR TO SAID TREATMENT, DIVIDING SAID RESIDUAL LIQUOR INTO SEVERAL STREAMS, AND RECYCLING ONE STREAM TO THE NEUTRALIZATION STEP WHEREBY THE DENSITY OF THE AQUEOUS AMMONIUM SULFATE SLURRY IS MAINTAINED BELOW A PREDETERMINED DENSITY WHILE MAINTAINING SAID SLURRY SUBSTANTIALLY SATURATED WITH ACRYLAMIDE.