Figure 3.

H₂O₂ generation from coal samples of varying sulfur content (i.e., FeS₂) in the presence of 1 mM EDTA. EDTA solutions were mixed with dry coal samples for about 2 min, filtered, leuco crystal violet (LCV) assay agents added, and absorbance at 590 nm recorded. LCV oxidation by H₂O₂ results in a colored product, which scales with H₂O₂ concentration. A 30 m²/L total surface area of each of the coal samples was achieved at mass concentrations ranging from 6 g/L to 26 g/L depending on the physical properties of each coal sample.