Rice Researcher Uses Glycerin to Produce Ethanol
A scientific discovery at Rice University could be the solution to a problem facing biodiesel manufacturers. As Houston Public Radio's Laurie Johnson reports, the biodiesel industry produces a glut of waste glycerin and there may be a new use for it.
Biodiesel is a cleaner, or greener, version of diesel fuel. The main byproduct of biodiesel is glycerin. Chemical Engineer Ramon Gonzalez says biodiesel production is at an all-time high, which means so is glycerin production and it has glutted the market.
"And as with any other product, if you produce a lot, is generated amount is larger than the demand then the price is going to go down. And that is what has happened with this glycerin. The price has gone down from 25 cents per pound let's say a year and a half or two ago, to about three cents per pound now."
From 25 cents down to three cents per pound is a significant loss when you consider many biodiesel producers count on selling huge amounts of waste glycerin to help offset costs. So Gonzalez, who is an assistant professor at Rice University, set out to find a way to convert glycerin into a more valuable product. And he found it by using a nonpathogenic strain of E. coli to ferment the glycerin.
"It turns out that the main product that you get is ethanol."
So Gonzalez took the byproduct of a biofuel and turned it into a renewable fuel. He says this process could allow manufacturers to produce biodiesel and ethanol all in the same facility. So not only could the value of glycerin go back up, but the cost of manufacturing ethanol could go down.
"And we show that we can produce pretty much ethanol from glycerin at half the cost that you would produce it from -- that you would produce it nowadays from corn."
Gonzalez says his research could be ready for production pilot demonstrations by the end of the year and biotech investors are expressing interest in expanding the process to production facilities. The research conducted at Rice University was funded by grants from the U.S. Department of Agriculture and the National Science Foundation. Laurie Johnson, Houston Public Radio News.