Back

Biography

Wei Du has completed her PhD and postdoctoral studies from South China University of Technology and Tsinghua University respectively. She worked as a visiting professor at MIT from 2009 to 2010. She has published more than 50 papers in reputed journals and has been serving as an editorial board member of Journal of Engineering. Based on the announcement of Elsevier in 2014, she is listed as one of Most Cited Chinese Researchers. She has applied for about 30 invention patents of China, in which 20 have been authorized in China and 3 international patent applications (PCT) have been authorized in many countries

Abstract

Biodiesel, as a renewable and environmental friendly clean fuel, derived from renewable oils/fats, has attracted considerable attention during the past decade. Although alkaline/acid based chemical process has realized the industrialization of biodiesel production in many countries, the reaction has many issues: It is energy intensive, recovery of glycerol is difficult, the acidic or alkaline catalyst has to be removed from the product and generates large quantity of waste water and with alkali as the catalyst, rather high requirements on the oil feedstock's quality and edible oil feed stocks such as soybean oil, rapeseed oil etc., are used as the feedstock, leading to serious concern on the food security. It is no doubt that for the sustainable development of biodiesel industry, the oil feedstock should be non edible oil sources. But currently, the widely used alkali based process is not suitable for the conversion of non edible oils since such oils usually contain free fatty acid and water. High requirements on the quality of oil feedstock has become the major challenge for the sustainable development of biodiesel industry, resulting in many small/medium sized biodiesel companies are closing down worldwide, such as in the United State, many European countries, Brazil, China etc (in China, almost all alkaline/acid based process close down now). Enzymatic approaches with lipase as the catalyst for biodiesel production can be effectively applied to the conversion of non edible oil feed stocks and it has many well recognized advantages over chemical methods: Moderate reaction conditions, lower energy input, easier product recovery and environmental friendly. The most important advantage is that enzymatic process can be applied to poor quality oil feedstock's conversion with varied content of free fatty acid and water and it is significant for the development of the second/third generation biodiesel. Although it is well recognized that enzymatic process has tremendous advantages versus alkalin/acid based catalytic process as illustrated above, the low stability (poor operational life) and the high cost of the lipase have been the main hurdle to the industrialization of lipase catalyzed biodiesel production. Tsinghua University has been engaged in enzymatic process for biodiesel production for more than 10 years and great breakthrough technologies/equipments are achieved successfully. With Tsinghua's technology, the lipase's operational life can be improved over 100-fold compared with traditional enzymatic approaches, leading to significant reduction in lipase cost. This technology can be applied to poor quality oil feed stocks, such as waste cooking oil, crude palm oil, algae oil etc., showing great potential for the second/third generation of biodiesel. And the whole production process is environmentally friendly and almost zero emission with no any acid/alkali used in the process. The technology has been commercialized successfully with 50,000 ton/year capacity in Hunan, China and it is the first commercialized facility worldwide by using enzymatic process for biodiesel production. Based on its environmental benefit and economic benefit, a bigger one (200,000 ton/year) is under construction in Guangdong. This process has also been demonstrated successfully in Brazil.