Jatropha seed photo courtesy of Mali Biocarburant, a Malian collective biodiesel producer.
One of the byproducts of the biodiesel refining process is glycerin: For every 10 pounds of biodiesel, about 1 pound of glycerin is also produced. In certain countries, Mali in particular, the glycerin is being used in soap making, so as to increase the revenue from a given quantity of feedstock.
In most other places, the rapid increase in biodiesel production volumes has resulted in producers having to pay to get rid of their leftover glycerin, Rice University researcher Ramon Gonzalez told Science Daily. This led Gonzalez and his team to research ways to convert glycerin into higher value chemicals.
E. coli used to convert glycerin into salable chemicals
Their research, published in the journal Metabolic Engineering, describes how a new fermentation process can allow E. coli and other bacteria to convert glycerin into fomate, succinate and other organic acids.
The technologies resulting from this research have been licensed to a Houston, Texas start-up which hopes to open a demonstration facility in the next year.
Gonzalez: "With fundamental research, we have identified the pathways and mechanisms that mediate glycerol fermentation in E. coli. This knowledge base is enabling our efforts to develop new technologies for converting glycerol into high-value chemicals."