CHAPEL HILL, N.C. --- Energy researchers have developed a two-step chemical process that improves an established method of making cleaner-burning alternative fuel from coal and other carbon sources by turning some of its waste products into diesel fuel. Researchers at the University of North Carolina and Rutgers told Newswise they have significantly augmented the Fischer-Tropsch method of making synthetic liquid fuels. Fuels produced by this method emit fewer particulates and less carbon monoxide than conventional diesel fuels. Maurice Brookhart, a chemistry professor at UNC, told Newswise that the team of researchers developed a dual-catalyst system that allows more Fischer-Tropsch materials to be converted to usable diesel fuels. The study is detailed in the April 14 issue of the journal Science.