DMSO, as an extraction solvent in aromatic hydrocarbon extraction, was first adopted by France's IFP method, which was presented at the 35th Chemical Industry Congress in Warsaw. Its advantages are: 1, high selectivity to aromatic hydrocarbons; 2. Infinite miscibility of aromatic hydrocarbons at room temperature; 3, the extraction temperature is low and does not react with alkanes, olefins and water; 4. No corrosion and toxicity; 5. Simple extraction process, less equipment and energy saving; 6. Insoluble olefins are suitable for oil products with high olefin content; 7. Solvent recovery can be used for back extraction. It is superior to the Sulfinol method of Shell and Udcx method of Global Pictures. China, Beijing and Liaoyang Petrochemical Company have been used in imported devices.
DMSO is insoluble in alkanes, so it is used for refining food wax and edible white oil and detecting cancer therapeutic substances.
DMSO is easily soluble in acetylene, and it can dissolve 33 liters of acetylene per liter of DMSO, while acetone can only dissolve 25 liters of acetylene. DMSO has a high boiling point and is easy to recover and regenerate. Therefore, it is used to recover liquefied petroleum gas acetylene and produce dissolved acetylene.
DMSO is soluble in organic sulfides, aromatic hydrocarbons and alkynes, and is often used to refine lubricating oil and diesel oil. DMSO and water do not freeze at-60℃ for 40%. Therefore, DMSO is used in gasoline, aviation fuel antifreeze and automobile antifreeze in cold regions. As a reaction solvent in the production of ferrocene as fuel oil additive, the reaction between dicyclopentadiene sodium and ferric chloride was accelerated and the yield was improved. In the production of nitroalkanes, the direct reaction of sodium nitrite and chloroalkanes in DMSO has a high yield. Recently, there have been many reports on petroleum processing, and new applications are also being continuously developed, especially in the industrial production of diesel refining abroad.
Application in synthetic fiber
The application of DMSO in acrylic fiber spinning was first patented by Toyo Rayon Co., Ltd., Japan. Acrylonitrile was polymerized in DMSO and spun directly in water bath without separation to obtain bulky, soft and easy-to-dye artificial wool. Its advantages are simplified process, high solubility, high boiling point of solvent, no toxicity, easy recovery, good product performance and low cost. Some acrylic fiber factories in Yuci, China, Dalian and Beijing are all produced by this process. Recently, it has also been used to produce carbon fiber from polyacrylonitrile. It is used to refine terephthalic acid ester in polyester resin production abroad. In addition, DMSO spinning and acrylonitrile polymerization are used to produce chlorine fiber.
Application in pharmaceutical production
As a reaction solvent, dimethyl sulfoxide is widely used in the synthesis of pharmaceutical intermediates. For example, fluoroaniline is prepared by the reaction of potassium fluoride with 3,4-dichloronitrobenzene in DMSO, which is widely used in the production of fluorine-containing drugs such as norfloxacin, trifluoronitrotoluene and ofloxacin. India is one of the major producers of fluorine-containing drugs, and imports about 4500t tons of DMSO every year. DMSO has been used in the synthesis of berberine, inositol nicotinate and sucrose fatty acid polyester and the extraction of traditional Chinese medicine.
Application in medical treatment
DMSO is soluble and permeable to many drugs, has anti-inflammatory and analgesic effects, promotes blood circulation and wound healing, and has diuretic and sedative effects. It can increase drug absorption and improve curative effect, so it is called "panacea" abroad. Various drugs are dissolved in DMSO, which can penetrate into the body without oral administration and injection, opening up a new route of administration. More importantly, it improves the local drug content in the ward and reduces the harm of other drugs in the body. There are many medical research reports abroad. In 1960s, Shenyang Pharmaceutical College, Beijing Institute of Medicine and China Drug Testing Center conducted a comprehensive toxicological examination and pathological anatomy in China. It is proved that the semi-quantitative LG50 value of DMSO in China is (22.4 1.4) g/kg, which is basically consistent with 2 1.4g/kg reported in foreign literature, and it is non-toxic and accords with pathological anatomy. Sarcocystin, B5 18, C6323, NA and other drugs used in Beijing Medical Research Institute have achieved good curative effects and obviously inhibited tumor growth. In animal experiments, the local drug concentration is 2 ~ 8 times higher than other drugs after anatomical detection. Foreign studies believe that cancer cells have a protective layer of keratin to prevent drugs from entering. DMSO has the ability to dissolve and penetrate keratin, so it can improve the curative effect. In 1960s, Peking Union Medical College Hospital and other 160 medical units conducted clinical trials in Benxi, and set up specialized clinics, which accumulated a lot of data. Practice has proved that it is effective for neurodermatitis, psoriasis, arthritis, bursitis, folliculitis, rheumatoid disease, otitis media, rhinitis, adnexitis, toothache, herpes zoster, hemorrhoid, sprain, lumbar muscle strain, burn and trauma. At present, drugs for external use, such as Guyouling, beriberi medicine and Furasone ointment, have been widely used in external preparations in major hospitals. DMSO was used by Veterinary Institute of Chinese Academy of Sciences to dissolve "Pass" to treat equine anemia and parasitic diseases. Especially in the traditional Chinese medicine extraction preparation, the content of useful components is improved and the drug effect is improved.
Application in pesticides and agricultural fertilizers
DMSO is a solvent, penetrant and synergist for pesticides and agricultural fertilizers. It has been reported abroad that antibiotics are dissolved in DMSO to treat fruit tree rot, pesticides are dissolved in DMSO to kill fruit stalks in trees and fruits, and 0.5‰ solution is sprayed on soybeans at flowering stage, which increases the yield by 65,438+00% ~ 65,438+05%. Adding 5‰ DMSO to various fertilizer aqueous solutions is more likely to cause personal poisoning.
It has been used in fruit tree mold disease in China. In plant experiments, impermeable drugs and dyes were mixed into DMSO aqueous solution and smeared on tree trunks. 12 hours later, branches, leaves, roots and fruits were all contained or colored, and the results disappeared after 24 hours. It shows that the drugs and pigments dissolved in DMSO can permeate and circulate, and can also be excreted through metabolism. This characteristic shows the application prospect of DMSO in agriculture, which needs further research.
Application in dyes
The capacity and output of DMSO used in Jilin Dye Factory to produce Ren Dan Fine Blue have been greatly improved, and it is still used in Sichuan Dye Factory. It is reported that DMSO is added in printing and dyeing to make dyeing uniform and eliminate color difference.
Application in coatings
Dimethyl sulfoxide, as a solvent, cosolvent and antifreeze, is widely used in waterborne latex paint. DMSO is used as a solubilizer in some paints because it has good solubility in various resins. More importantly, it is used as a paint remover. Adding alkali or nitric acid to DMSO can remove various paint films including epoxy resin.
Application in antifreeze
The freezing point of pure DMSO is 18.45℃, and DMSO containing 40% water does not freeze at -60℃, and releases heat when it meets water and snow. This characteristic makes DMSO a component of automobile antifreeze, brake oil and hydraulic oil. When the low temperature exceeds -40℃, ethylene glycol antifreeze is no longer applicable. Moreover, the boiling point is lower than DMSO, which is toxic and easy to produce gas resistance. DMSO antifreeze is used as deicer, paint, antifreeze for all kinds of latex, antifreeze for gasoline and aviation fuel, antifreeze for bone marrow, blood and cryopreservation in the northern cold region.
Application of gas separation
In petroleum processing, chemical tail gas recovery and gas separation, DMSO is used as a solvent for gas separation because of its solubility in aromatics, alkynes, sulfides, nitrogen dioxide and sulfur dioxide.
Application in synthetic resin
Dimethyl sulfoxide is used as polymerization solvent of polysulfone resin in production. DMSO is soluble in many natural and synthetic resins, but soluble in nylon, polyester and polyvinyl chloride resins at moderate temperature. DMSO is used for artificial leather processing, and can also be used as cleaning agent for polyurethane reaction kettle and solvent for acrylonitrile polymerization.
Application in coking by-products
In the production of anthraquinone, it is used to refine anthracene. Adding DMSO to anthracene oil to extract refined anthracene, the content of one-time extraction can reach above 98%, DMSO can be recovered without water back extraction, and the process is simple. In China, besides naphthalene refining, it is also used to recover organic sulfide in coke oven gas separation.
DMSO is used as an extraction additive of gold, platinum, niobium, tantalum, rhenium and radioactive elements in national highways to improve the selectivity, solubility and antifreeze of low-temperature crystallization.
Application in electronic industry
DMSO is used as the electrolyte of Farah-class ultra-large capacity capacitor-liquid electric double layer capacitor. At present, the capacitor has only micro farad capacity, but this capacitor can reach 1 ~ 100 farad. Such as 3 ~ 5V 10F in Japan and1.6v10f in the United States, are used as energy storage elements in solar power supply systems and as information protection power sources and memory elements in computers and robots. DMSO is widely used in the cleaning of electronic components and integrated circuits. It has the function of removing organic matter, inorganic matter and polymer at one time, and is non-toxic and tasteless, and easy to recycle.
Application in organic synthesis
DMSO plays a dual role in chemical reactions, such as reaction solvent and reaction attempt. Some unrealizable reactions can be carried out smoothly in DMSO, which can accelerate and catalyze some chemical reactions, improve yield and reform product performance.
1, nucleophilic substitution reaction: DMSO is a nucleophilic dissociation solvent of alkyl halide and sulfonate, which can generate adducts. The reaction rate is 155 times faster than that of ordinary aprotic solvent, which plays an important role in alkylation reaction.
The reaction of alkyl halide with inorganic cyanide to prepare nitrile is not easy to react. In DMSO, the reaction speed is fast and the yield is high. The conversion of sodium nitrite and alkyl halide or α -halogenated ester into nitro compounds has a similar effect.
It is not easy to prepare aromatic fluoride by Swarts reaction, but potassium fluoride and chlorinated aromatic hydrocarbon can be easily replaced in DMSO, so fluorine exchanger can be prepared in high yield. Bromobenzene and potassium tert-butoxide can generate tert-butyl ether in DMSO without heating.
2. Elimination reaction: Benzyl alcohol and aliphatic tertiary alcohol are diluted in DMSO, and sulfonate and alkyl halide are heated in DMSO to generate olefins. The reaction of Cope elimination can be carried out smoothly in DMSO at room temperature, and the reaction speed is 105 times faster than that in water.
3. Electrophilic substitution: In DMSO, electrophilic substitution can be carried out quickly on some saturated carbon atoms. For example, when sodium enolate is alkylated with haloalkane in benzene, adding 0.65mol/L DMSO can make the reaction 20 times faster in DMSO than in dioxane. The exchange rate of hydrogen and heavy hydrogen in organic compounds catalyzed by alkali is 109 times higher in DMSO than in alcohol. The racemization rate of asymmetric α -carbon in DMSO is 106 times higher than that in tert-butanol.
4. Double rearrangement: Under the catalysis of potassium tert-butoxide, double bond rearrangement can be generated in DMSO, and the reaction can be carried out uniformly at low temperature.
5. Other reactions: There are many reports about using DMSO as the reaction solvent. For example, quaternization of triethylamine with iodoethane, transesterification of higher fatty acids with glycerides, esterification of non-reducing sugars in the presence of sodium alcoholate, cyanoethylation of alcohols, catalysis of the reaction of phenyl isocyanate with thiols, etc. In DMSO, it has an accelerating effect. DMSO can also be used as a reaction solvent in ester condensation and polymers. Such as: Dicckmann reaction, dextran depolymerization, trypsin conformation transformation, acylation and so on.
In a word, DMSO opened up a new way of chemical preparation, accelerated the reaction speed, improved the yield and prepared many new substances. It is not only a solvent, but also a new chemical reaction means, which has important theoretical and practical significance.
Application of hydrothermal synthesis
It can be used as a solvent in hydrothermal synthesis. DMSO in the reaction kettle will decompose above 120℃, producing toxic gas, which has dizziness symptoms and very unpleasant smell. Pay attention to protection when using. If the temperature exceeds 120℃, open the kettle in a fume hood with a gas mask.
Application in cell cryopreservation
Dimethyl sulfoxide is an important osmotic cell protective agent. In the process of cryopreservation of cells at low temperature (-200℃), it is necessary to use a cryoprotectant containing DMSO to prevent the damage caused by the formation of ice crystals in intracellular fluid, the change of osmotic pressure and the disorder of cell structure. DMSO can quickly penetrate the cell membrane and enter the cell, lower the freezing point, delay the freezing process, increase the ion concentration in the cell, reduce the formation of ice crystals in the cell, and thus reduce cell damage. The cytotoxicity of dimethyl sulfoxide was inhibited at low temperature. Be quick when resuscitation, and wash off dimethyl sulfoxide as soon as possible, otherwise it will cause serious toxicity to cells. Dimethyl sulfoxide is the best antifreeze at present, but it is also a chemical reagent with great cytotoxicity. The results showed that when the DMSO concentration in the medium was 10%, the cell growth inhibition rate was close to 100%. When the concentration is 1‰, the inhibition rate is 35%. Even at the concentration of 0.04‰, DMSO has an adverse effect on cell growth.
Application of PCR
Adding 5% glycerol or 5% DMSO to the mixture of PCR system can enhance the specificity and inhibit the formation of primer dimer.