Sodium Saccharin: What It Is and Its Applications

Sodium saccharin is one of the oldest artificial sweeteners on the market. Saccharin is a non-nutritive artificial sweetener that appears as a white crystalline powder, and it is soluble in water. It is about 300 to 400 times sweeter than sugar, so you only need a small amount to achieve a sweet taste. Sometimes, saccharin is combined with aspartame, another low-calorie sweetener commonly found in diet sodas. The use of this artificial sweetener can help reduce sugar consumption. Notably, it is very inexpensive in the global market. Saccharin is 161 times sweeter than sugar and, unlike sugar, contains very few calories and does not raise blood sugar levels. The production of saccharin is easy, and it is stable under heat.

Production

Sodium saccharin can be produced using phthalic anhydride. The raw materials required for this method include phthalic anhydride, methanol, ammonia, liquid chlorine, sodium hydroxide, hydrochloric acid, sulfuric acid, sodium nitrate, copper sulfate, sodium bicarbonate, liquid sulfur dioxide, toluene, and activated carbon. Here, we focus on the production of saccharin using toluene.

The production of saccharin involves three stages:

1. First, toluene is sulfonated and converted into ortho-toluene chlorosulfonic acid, which is obtained through a reaction with chlorosulfonic acid. This reaction occurs at very low temperatures. After that, it is filtered and combined with ammonia, stirred for a few minutes, and filtered again. The crude ortho-toluene sulfonic acid is separated by filtration.
2. In the next stage, ortho-toluene sulfonic acid and sodium hydroxide are dissolved in water, and potassium permanganate is slowly added while maintaining a temperature of 40 °C. A small amount of sodium bisulfite is then added to decolorize the resulting solution, and hydrochloric acid is used to slightly acidify the mixture before filtering to remove any unreacted ortho-toluene sulfonic acid.

Applications

1. Electroplating Industry:
   • This substance is useful in electroplating as an additive in solutions and metalworking adhesives. For example, in nickel plating, it is used as an electrolyte (a substance that dissolves in solution and conducts electricity). Sodium saccharin is used in nickel plating to achieve a brighter finish. It is also used in gold and palladium plating.
2. Food Industry:
   • It can be used in toothpaste and mouthwash, and as a non-nutritive sweetener and stabilizer in various foods and beverages. This compound is a key chemical in the production of pesticides and herbicides and acts as a catalyst in the production of anaerobic adhesives (adhesives that cure without oxygen). Anaerobic adhesives are referred to as lock connections or seals and are used for sealing hard parts. Compared to aspartame, sodium saccharin is heat-resistant and can be used in cooking without losing its sweetness.
3. Pharmaceutical Industry:
   • The pharmaceutical industry uses this salt as a coating for medications. Multivitamin tablets and chewable tablets often contain a small amount to improve their taste. Sodium saccharin is used to enhance the flavor of toothpaste and sweeten its taste. Since this compound is very sweet, only small amounts are needed to improve the flavor of toothpaste. According to studies conducted, this toothpaste additive does not provide any health benefits for teeth; it simply acts as a sweetener.