Nylon 6 is produced from polymerisation of caprolactam. Caprolactam is polymerised to Nylon 6 polymer by ring opening polymerisation at 240-270 degrees C in presence of water, which opens the ring structure of the caprolactam to give amino caproic acid. Reacting SO2 with ammonium nitrite & ammonium carbonate which results in production of hydroxylamine disulphonate finally hydrolysis of hydroxylamine disulphonate at 95 degrees to yield hydroxylamine sulphate & ammonium sulphate as by-product.