By Mitch Emmons (firstname.lastname@example.org)
AU RESEARCH USING WASTE PLASTICS, COAL TO PRODUCE USABLE FUELS
AUBURN -- Auburn University researchers are working on ways to convert waste plastics and coal into viable fuels -- a technology that once perfected will reduce the amount of plastics buried in landfills and cut U.S. dependency on foreign oil.
Through the Consortium for Fossil Fuel Liquefaction Science -- comprised of AU, West Virginia University and the universities of Kentucky, Pittsburgh and Utah -- work is underway to combine coal and other fossil fuels such as waste oil with plastics, tire rubber and paper materials to produce fuel oils and transportation fuels.
Six professors at AU -- Christine Curtis, an alumni professor in the Department of Chemical Engineering and an associate vice president for research; Chemical Engineering Professors Ray Tarrer and James Guin, and Associate Professor Mahmoud El-Halwagi; and Professors S.D. Worley and Charles Neely in the Department of Chemistry with AU's College of Science and Mathematics -- are working on the project.
Curtis says her research focus is on the liquefaction of waste plastics and tires.
Liquefaction -- turning materials from a solid to a liquid state -- is not simply melting them, according to Curtis. It is a process in which the chemical compounds - - polymers -- are broken down into smaller molecules that can be used as fuels.
"Plastics don't liquefy well, so catalytic treatment, using a cracking or hydrocracking catalyst, is needed," Curtis says. "Coal, however, does not always perform well with these catalysts, so what we're trying to do is pre-liquefy the plastics and use the liquid portion as a solvent in the coal with a catalyst that does perform well with coal. That particular two-stage process looks quite promising."
The materials are combined in a reaction chamber with hydrogen gas at a high temperature -- about 440 degrees C -- to break down the polymers and remove the unwanted metals present, Curtis says.
"Depending on the materials that we start with and the degree of further refining, we can obtain a gamut of fuel products...from solvents...to diesel fuels... to gasolines and high quality jet fuels," she said.
In addition to its environmental and economic aesthetics, the waste co- processing technology would result in a new industry providing a new source of domestic fuels, according to Curtis.
"It would be desirable to have these co-processing plants located at a refinery," she said. "That way the product from the co-processing of these plastics and coal could be fed directly to the refinery for further upgrading.
"Even with two-stage liquefaction, the fuel will not be of the quality wanted without further refining to get a desirable and marketable product."
According to Department of Energy, Americans generate 90 million tons of waste paper and plastic, 350 million waste tires and 1.4 billion gallons of waste oil each year. Estimates are that these materials co-processed with coal could produce 300 million barrels of usable fuel oil -- essentially offsetting one month of current U.S. oil imports.
"This type of process probably is what we (as a country) should be looking at rather than imports," Curtis said.
CONTACT: Curtis, 334/844-4784.