What is dimethyl carbonate

Dimethyl Carbonate (DMC) is a colorless and volatile liquid whose properties include low toxicity and excellent solubility. It plays a vital role in organic synthesis and has been widely used in industries such as new energy batteries, pharmaceuticals, pesticides, fragrances, dyes, coatings, plastics and rubber. Next, we'll take a closer look at the chemistry of dimethyl carbonate, its wide range of applications, and the main processes used to produce this key organic intermediate.

Chemical Properties

Dimethyl carbonate, with the chemical formula C3H6O3 and molecular weight of 90.08, belongs to the carbonate group of compounds. These compounds are usually soluble in organic solvents and are sensitive to hydrolysis. At room temperature, dimethyl carbonate appears as a liquid with a boiling point of about 90°C. It also has a low vapor pressure and a high oxygen index, which ensures its safety during storage and transportation.

Application Areas

Dimethyl carbonate has a wide range of applications in many industries. In the field of new energy, it is known as the “plasma” of new energy vehicles, especially in the manufacture of lithium batteries, as the electrolyte solvent, carrying lithium ions and other electrolyte ions, to ensure the smooth flow of the electrolyte, providing key support for the normal work of lithium batteries. In addition, dimethyl carbonate also plays an indispensable role in many fields such as pharmaceuticals, pesticides, spices and dyes, coatings and plastics, and rubber industry.

Main process routes

Currently, the ester exchange method is the mainstream process for the production of dimethyl carbonate. The method uses CO2 and ethylene oxide or propylene oxide as raw materials, and the by-products are ethylene glycol or propylene glycol. Since CO2 can be sourced from the exhaust gas emitted from the plant, the process not only reduces carbon emission, but also facilitates the comprehensive utilization of resources and environmental protection. Despite the challenges of large investment, high cost and complex separation technology, the mild reaction conditions and high yield characteristics of the ester exchange method still make it a relatively preferable choice.

Preparation process

At present, the preparation process of dimethyl carbonate mainly includes carbonylation method, urea alcoholysis method and phosgene method. Carbonylation method uses methanol and CO2 as raw materials, and synthesizes DMC through the action of catalyst, but this method has the problems of equipment corrosion, short catalyst life, and wastewater discharge. Urea alcoholysis method, on the other hand, uses urea and methanol as raw materials, and reacts under high pressure, high temperature and catalyst to generate DMC, which has lower cost, but the reaction conditions require strict requirements and there is the problem of urea decomposition contaminating the product. In addition, the phosgene method was once a traditional production method for DMC, but it has been eliminated due to the high toxicity and corrosiveness of phosgene and the environmental problems of sodium chloride emission.

Comparison and selection of process routes

Each process route has its unique advantages and disadvantages. Although the ester exchange method is mature, the raw material cost is relatively high; the carbonylation method has certain advantages in cost, but the technical requirements are high and there are safety hazards; the urea alcoholysis method has a lower cost, but the product purity is relatively low. Therefore, when choosing the process route, it is necessary to comprehensively consider the technical feasibility, economic cost and environmental protection requirements and other factors.

Future Prospects

With the increasingly stringent environmental requirements and the continuous improvement of technology, the production of dimethyl carbonate is developing towards high efficiency, environmental protection and scale-up. Future research will mainly focus on optimizing reaction conditions, reducing production costs, and developing new catalysts and separation technologies to realize the greening and industrialization of DMC production.
Ecovia as a key producer of lithium solvent DMC, not only provides DMC, but also has a rich product line including five electrolyte solvents,  and a variety of additives, forming a complete supporting system of solvents and lithium salts, and enjoying a prominent position in the industry. The company is deeply engaged in the field of new energy and new materials, and is committed to providing high-quality products and solutions for global customers, promoting the progress of the new energy industry, and committing itself to creating a greener and more environmentally friendly living environment for mankind.