Scientists use biomass to make ethylene glycol

Chinese scientists have recently launched trial production of bio-ethylene glycol from straw sugar, creating a more eco-friendly way to make as much as 1,000 metric tons a year of the industrial compound, experts said.

Ethylene glycol is an important chemical raw material with a global annual consumption of more than 30 million tons, said Zheng Mingyuan, a researcher at the Dalian Institute of Chemical Physics, which is part of the Chinese Academy of Sciences.

"In China, as a major producer and consumer of EG, the annual consumption exceeds 20 million tons. EG is used as a primary raw material for making clothing fibers, plastic products like beverage bottles and many other things," he said.

Professor He Mingyuan from East China Normal University said previously, EG was mainly produced using petroleum or coal as raw materials, which are nonrenewable resources. The production process resulted in high carbon dioxide emissions and energy consumption.

"In terms of resource utilization, biomass is the only organic carbon source that has the potential to replace fossil fuels," said He, who is also an academician of the Chinese Academy of Sciences. "With new technologies that can change the energy system, I feel very excited."

He emphasized that the effective utilization of biomass is a crucial issue in green and sustainable development, which scientists have been addressing since recognizing the energy value of biomass.

"The transformation of living organisms into fossil fuels and then being used by humans is a large carbon cycle. By processing and utilizing biomass, we can bypass this cycle. For example, agricultural straw can be directly utilized, forming a short loop that enhances energy efficiency," he said, adding that biomass can never be depleted as it is a renewable energy source.

In 2008, a team led by Zhang Tao at the Dalian Institute of Chemical Physics pioneered the reaction of directly catalyzing cellulose to produce EG internationally. The technology has obtained over 40 invention patents and possesses complete independent intellectual property rights.

"This provides an important technological solution for upgrading the EG industry chain and the development of the green chemical industry in China," said Zhang, who is also an academician of the Chinese Academy of Sciences. "It is of great significance for environmental protection, achieving China's dual carbon goals and sustainable economic development."

Over the past 16 years, the research team has continued to improve the long-term stability of the catalyst, expand the range of raw materials and reduce production costs, finally transforming the technology from a scientific discovery in a laboratory to a technology suitable for industrial production.

Zheng, the researcher, said the cost of bio-EG produced from bio-based raw materials through catalysis is more expensive than traditional coal-based production, but the compound is more pure — 99.9 percent — and of better quality.

In addition, the ultraviolet transmittance meets the national standard for polyester-grade EG.

"The technical verification at the 1,000-ton level can eliminate potential issues in mass production and serve as the basis for designing industrial plants at the 10,000-ton level," Zheng said. "This technological breakthrough means that the technical preparation for 10,000-ton industrial production is now in place."

yandongjie@chinadaily.com.cn