What Are the Uses of Dimethyl Carbonate?

Understanding Dimethyl Carbonate

Dimethyl carbonate is an organic compound that can be viewed as the dimethyl ester of carbonic acid. It is a flammable clear liquid with a boiling point of 90°C and is insoluble in water. It can be used as a methylation reagent. Compared to other methylation reagents such as iodomethane and dimethyl sulfate, dimethyl carbonate is less toxic and can be biodegraded.

Dimethyl carbonate has a wide range of applications. It can replace phosgene as a carbonylation reagent, replace dimethyl sulfate (DMS) as a methylation reagent, and serve as a low-toxicity excellent solvent and a potential gasoline additive.

Applications of Dimethyl Carbonate

Replacement of Phosgene as a Carbonylation Reagent

Phosgene has the advantage of high reaction activity, but its byproduct is highly toxic and corrosive. Therefore, it faces enormous environmental pressures. Against the background of increasing environmental policy pressure, phosgene will gradually be replaced by safer reaction reagents, such as dimethyl carbonate, one of the common green organic solvents which have similar nucleophilic reaction centers. When its carbonyl group is attacked by a nucleophile, the carbonyl-oxygen bond breaks to form a carbonyl compound, and the byproduct is methanol. Therefore, dimethyl carbonate can replace phosgene as a safe reaction reagent for synthesizing carbonate derivatives, such as aminomethylformate pesticides, polycarbonate (PC), isocyanates (MDI, TDI, etc.), among which polycarbonate (PC) is the field with the largest demand for dimethyl carbonate in the future.

Replacement of Dimethyl Sulfate as a Methylation Reagent

Dimethyl sulfate is similar to phosgene and also has high toxicity, with high sulfate pollution byproducts. When the methyl carbon of dimethyl carbonate is attacked by a nucleophile, its alkoxy bond breaks to produce the methylated product. The effect is similar to that of DMS, but the reaction yield is higher, and the process is simpler. Its main uses include the synthesis of organic intermediates, pharmaceuticals, and pesticides.

Low-Toxicity Excellent Solvent

Made by a professional dimethyl carbonate supplier, dimethyl carbonate has excellent solubility, a narrow melting and boiling point range between 4℃ and 93℃, high surface tension, low viscosity, and a high evaporation temperature and rate. Therefore, it can be used as a low-toxic solvent for the coatings and pharmaceutical industries. Dimethyl carbonate also has high flash point, low vapor pressure, and high lower explosive limit in the air, making it a green solvent that combines cleanliness and safety.

Potential Gasoline Additive

The oxygen content in dimethyl carbonate molecules is high, reaching 53%, and it can effectively increase the octane rating. It also has properties such as immiscibility, low toxicity, and rapid biodegradability. When the same oxygen content is achieved, the amount of dimethyl sulfate used in gasoline is 77% less than that of methyl tert-butyl ether (MTBE), thereby reducing the total emissions of hydrocarbons, carbon monoxide, and formaldehyde from automobile exhausts. In addition, it overcomes the shortcomings of commonly used gasoline additives being soluble in water and polluting groundwater sources, making dimethyl carbonate one of the most promising gasoline additives to replace MTBE.