ABSTRACT
T h e p resence o f sulfur in coal is k n o w n to b e a m ajo r cau se o f acid rain p rec u rso rs [1]. S u lfur is p re se n t in co a l in in o rgan ic and o rg an ic form s. T h e ino rg an ic su lfur o cc u rs m o stly as d isu lfides and a sm all am o u n t o f sulfates. S ulfide m inerals include p y rite (F eS 2), d im o rp h ic m arcasite (F eS ), sphalerite (Z nS ), g a len a (P b S ), cha lco p y rite (C eF eS 2), p y rrh o tite (F e bxS), and a rsen o p y rite (F eA sS ). T h e p y rite w h ich is th e p red o m in an t su lfu r m ineral in coal generally o ccu rs in m ic ro m etrie sized crysta l as fram b o id s o f 10 to 4 0 p m [2 ]. M inera l su lfa tes inc lude b a rite ( B a S 0 4), g ypsum ( C a S 0 4 2 H 20 ) , anhydrite ( C a S 0 4), and a nu m b er o f iro n su lfates. S tro n g ac ids such as n itric acid and ch lo ric acid can read ily d isso lve m o st o f th e se m ineral sulfates.
