The production history of soda ash is as follows:
The earliest invention of the method of artificially synthesizing soda ash was at the end of the 18th century. France's Lublan used Glauber's salt, limestone and coal to reduce and carbonate at high temperatures to obtain Black ash, a crude product mainly containing Na2CO3, is leached, evaporated, refined, recrystallized and dried to obtain heavy soda ash with a purity of approximately 97%. In 1861, Belgian Ernest Solvay independently invented soda ash and obtained a patent.
Because technical secret protection has never been widely used, a breakthrough was made in the United States in the 1920s. In particular, Hou Debang, a famous Chinese chemical expert, published the book "Soda Ash Manufacturing" in 1932 and kept it secret for 70 years. In 2001, the Solvay Law was announced to the world. Hou Debang also created Hou's alkali production method from 1939 to 1942 and established a pilot workshop in Sichuan.
In 1952, a joint alkali production workshop was established in Dalian Chemical Plant. The NA method introduced by Asahi Glass Company of Japan is essentially a compromise method between joint alkali and ammonia alkali. The ratio of soda ash and ammonium chloride can be adjusted at will.
Application fields of soda ash
1. The glass industry is the largest consumer of soda ash, with 0.2t of soda ash consumed per ton of glass. Mainly used in float glass, picture tube glass shell, optical glass, etc.
2. Used in chemical industry, metallurgy, etc. The use of heavy soda ash can reduce flying alkali dust, reduce raw material consumption, improve working conditions, improve product quality, reduce the erosion of alkali powder on refractory materials, and extend the service life of the kiln.
3. As a buffer, neutralizer and dough improver, it can be used in pastries and flour foods, and should be used in appropriate amounts according to production needs.
4. Used as a detergent for wool rinsing, bath salts and medicinal purposes, and an alkali agent in tanning.
5. Used in the food industry as a neutralizing agent and leavening agent, such as in the manufacture of amino acids, soy sauce and flour-based foods such as steamed buns, bread, etc. It can also be mixed into alkaline water and added to pasta to increase elasticity and ductility. Sodium carbonate can also be used to produce MSG.
For the above content, refer to Baidu Encyclopedia-Sodium Carbonate