Coal is decaying plant or animal matter that has been altered by some biological process and geological process over a long period of time. Biological processes have the ability to remove organic sulfur but have not been used commercially (Ohtsuka, 2000). One advantage that biological processes hold over other methods is that the temperature and pressure needed can be very low, reducing energy, while other processes can have a temperature of up to 1350˚C and a pressure of 140 atm (Faison, 1991). The biological process of pyritic sulfur removal is generally believed to have two methods: the indirect method and the direct method. The indirect method removes pyritic sulfur by oxidizing pyritic sulfur using ferric ions. This route is 106 times slower than the direct route (Groppo, Parekh, 1993). The direct method is defined as a process in which microorganisms attach to the surface of the pyrite and enzymatically oxidize the sulfur, proving to be much more efficient with