SUSTAINABLE CHEMICAL PROCESS FOR ISOLATION OF 1-AMINO-8-NAPHTHOL-3,6-DISULPHONIC ACID (H-ACID) WITH INHERENT RECYCLE OF ALL ACIDIC STREAMS GENERATED DURING ISOLATION AND WASHING OF H ACID

摘要

Isolation of Naphthalene Sulphonic Acid Compounds is achieved with acidification of alkali fusion mixture with dilute sulphuric acid to precipitation at the predetermined conditions temperature, time and pH and Naphthalene Sulphonic Acid Compounds is separated as a partial alkali metal salt by precipitation and separated by filtration. The resulting filtrate after recycle treatment containing soluble Naphthalene Sulphonic Acid Compounds and/or a salt thereof after recycle treatment is used as a starting reaction medium, top up reaction medium, dilution reaction medium for said subsequent isolation of Naphthalene Sulphonic Acid Compounds. Isolation of Naphthalene Sulphonic Acids can be achieved by two methods viz. forward isolation and Reverse isolation.