The Production Method of Sodium Saccharin
The traditional method for making saccharine was developed in 1879 by Fahlberg and Remsen, and consists of?oxidizing o-toluene sulfonamide (OTSA)?by use of an oxidizing agent such as potassium permanganate. This method is still used today by many saccharine producers?after updating the new method by electrolytic catalytic oxidation.?New electrolysis method have lower cost and more environmentally friendly.
In China, most of manufacturers use another method -- Phthalic anhydride method
The phthalic anhydride method is original creation in China. The raw materials used are phthalic anhydride, methanol, ammonia, liquid sodium hydroxide, liquid chlorine, hydrochloric acid, sulfuric acid, sodium nitrite, copper sulfate, liquid sulfur dioxide, toluene, sodium bicarbonate, activated carbon, etc. The production technique?is: take phthalic anhydride as raw material is through amidate action, esterification, doazo reaction, replacement(metathesis)reaction, chlorination reaction, aminating reaction, acid out, neutralization reaction, make soluble saccharin solution, this solution, through decolouring, concentrated, crystallization, drying, dry, is made to soluble saccharin finished product.?Aminating reaction in traditional soluble saccharin production process is to take ammoniacal liquor as raw material, and the adjacent sulphuryl chloride?methyl benzoate obtaining with chlorination reaction reacts and generates saccharin ammonium.
Through the techniques are different, but they finally come into being the same product sodium saccharin.