In recent years, with the high price of international oil, biodiesel as an alternative energy source is widely popular. And as the biodiesel industry gradually heats up, cheap glycerin emerges in large quantities.
It is understood that the biodiesel production process will produce a large amount of glycerin by-product. Every 10 tons of biodiesel production will produce 1 ton of glycerin. This will have a very big impact on the traditional glycerin production enterprises. Many traditional glycerin producers will be forced to close down. The increase of the supply of cheap glycerol by-products will certainly drive the rapid development of new glycerol-based raw material industries.
The preparation of epichlorohydrin by “glycerol method” has become a hot spot in the industry. Last year, Dow Chemical and Solvay announced the construction of large scale epichlorohydrin production plants using “glycerol method” almost simultaneously. And several manufacturers have implemented or launched the construction plan of epichlorohydrin using “glycerol” process in China. A global climax of epichlorohydrin development has been formed.
According to the experts of China Epoxy Resin Industry Association, “glycerol method” will become the main character of the development of epichlorohydrin. Epichlorohydrin is expected to become the largest application area of glycerol.
At present, the demand for epoxy resin is increasing rapidly, and epichlorohydrin, one of the two major raw materials for epoxy resin, has entered a period of rapid development. Its traditionally mostly used propylene as the initial raw material.
Entering the 21st century, the global economic recovery is pulling petrochemical downstream products, propylene shortage is getting bigger and bigger, and oil keeps building a high price platform. Further pushing up the price of propylene and its downstream products. Epichlorohydrin prices remain high. In this context, the preparation of epichlorohydrin by “glycerol method” is facing a great opportunity. Because of its abundant raw material resources and low price, the production of epichlorohydrin by glycerol can escape from the constraint of propylene scarcity.
At present, in addition to the “glycerol method”, the main production processes of epichlorohydrin are propylene high-temperature chlorination and propylene acetate. The latter two use propylene as the upstream raw material. Among them, the high temperature chlorination process requires high temperature conditions, and the equipment operates under high temperature for a long time. Once faced with safety hazards there will be more abnormal downtime.
The process also faces the same catalyst technology problems as the “propylene acetate” process. From the situation of domestic manufacturers using “high-temperature chlorination” and “acrylate acetate”, it takes a long time to start operation and 1-2 years to run normally after the completion of the plant. During the operation, catalyst problems and equipment problems are sometimes troubled.
Another major advantage of the “glycerol method” is to achieve clean production. Dow Chemical, as the world’s largest producer of epichlorohydrin, has mastered the mature “glycerol method” process, and it has planned to build a “glycerol method” epichlorohydrin plant in China, with a production capacity of 100,000 tons/year. Solvay, a major European chlor-alkali manufacturer, has also developed the “glycerol” process and plans to build a 100,000 tons/year plant using this process.
China started to study the technology of “glycerol method” more than 40 years ago, and Guangzhou Auxiliary Plant was the first to adopt “glycerol method” to produce epichlorohydrin in 1965, and after 1968 Wuxi Resin Plant and Shenyang Chemical Plant built “propylene high temperature chlorination” plant. After 1968, Wuxi Resin Factory and Shenyang Chemical Factory built “propylene high-temperature chlorination” plants.
As glycerol was tight and the consumption of “glycerol method” was high, the process of “glycerol method” gradually faded out of view. According to the experts of China Epoxy Resin Industry Association, the research on this technology in China has not been interrupted. At present, Shanghai Reagent Factory and Zhangjiagang Factory are running reagent grade “glycerol method” device, and the quality is far better than the current industrial grade device. Although there is still work to be done to scale up to a platform of more than 10,000 tons, this technology has been mastered in general.
On the whole, since the simple “glycerol method” process is relatively simple, the general chemical enterprises can master it freely, and the by-product glycerol will increase rapidly as the biodiesel industry is heating up, so the by-product glycerol is expected to be the main character in the new round of development of epichlorohydrin.