Dimethyl sulfoxide is a transparent, colorless, odorless and slightly bitter liquid. It can dissolve various polar organic gases and liquids except alkanes. or polymers, which are aprotic polar solvents. Due to its special solvent effect on chemical reactions and dissolution properties of many substances, dimethyl sulfoxide has always been called the “universal solvent”. Dimethyl sulfoxide can penetrate the dissolved drugs into the human body through the skin and is harmless to the body. It can replace oral administration or injection, so it is also called the “panacea”. Dimethyl sulfoxide is widely used in many fields such as pesticides, medicines and electronic materials. It is mainly used to synthesize fluorine-containing chemicals and as an intermediate solvent for medicines and pesticides. In recent years, it has been used in the electronic industry and carbon fiber fields. increase.
Dimethyl sulfoxide production technology
The main raw material for the production of dimethyl sulfoxide is dimethyl sulfide. Due to the raw materials used to synthesize dimethyl sulfide Different routes and oxidants used in the oxidation of dimethyl sulfide result in a variety of production methods for dimethyl sulfoxide. The main sources of raw materials for dimethyl sulfide include papermaking black liquor recovery, carbon disulfide-methanol synthesis, and hydrogen sulfide-methanol synthesis of dimethyl sulfide. The United States uses black liquor from paper mills to recover dimethyl sulfide, France and Japan use hydrogen sulfide and methanol to synthesize dimethyl sulfide, and my country mainly uses carbon disulfide and methanol to make dimethyl sulfide. Since hydrogen sulfide is a by-product of other processes, raw materials are easily available, utility consumption is low, and the unit cost is low, the synthesis of dimethyl sulfide from hydrogen sulfide and methanol is the development direction of the dimethyl sulfide process.
Dimethyl sulfide oxidation methods include nitric acid method, hydrogen peroxide method, ozone method and nitrogen dioxide method. The equipment of the nitric acid method is seriously corroded, and a lot of alkali is consumed when neutralizing nitric acid; the hydrogen peroxide method is expensive and not suitable for industrial production; the conversion rate of the ozone oxidation method is too low; the nitrogen dioxide method is a more advanced production method, and currently all industrial production All devices use this method. There are two processes of oxidation reaction: liquid phase oxidation and gas phase oxidation. Gas phase oxidation has strict requirements on operating conditions, otherwise it is easy to explode. Currently, liquid phase oxidation method is mostly used in industry.
