Winter 2007
In This Issue:
Focus On Energy
A Method for Making Ultra-Clean Transportation Fuels
Until an alternative energy economy is put into place, we will have little choice but to rely on transportation fuels made from petroleum. Dr. Chunshan Song, associate professor of fuel science and director of the Clean Fuels and Catalysis Program at the Energy Institute, is working on ways to make the inevitable use of fossil fuels less harmful to the environment.
A novel process for cleaning sulfur, the key culprit in acid rain and a particularly nasty atmospheric pollutant that forms with water and oxygen in the atmosphere to make sulfuric acid, is being developed by Song and his colleagues at Penn State to create ultra-clean jet fuel, gasoline for passenger vehicles, and diesel for trucks and buses.
The current industrial method of desulfurization requires the fuel to be processed at high temperature and pressure using hydrogen gas. Song's method, called PSU-SARS for selective adsorption for removing sulfur, uses transition metals as adsorbents that selectively interact with sulfur in the presence of aromatics. The aromatics remain in the fuel to maintain a higher octane rating. The process takes place at room temperature, under ambient pressure, and without the use of hydrogen or other reactive gases.
In the lab, the process has been shown to deliver ultra-low-sulfur gasoline, jet fuel, and diesel fuel at less than 1 part per million, far below the strict EPA regulations that call for less than 30 ppm of sulfur for gasoline and 15 ppm for diesel. In addition, the process could be tailored for use as an on-board sulfur removal system for fuel cell vehicles.
As the sources of crude oil become dirtier and dirtier, Song and his research team hope that the PSU-SARS method can be transposed from the laboratory scale to the floor of oil refineries. To that end, Penn State has filed two patent pplications on the SARS process.
