Probing reactivity sites on pyrite-oxidative interactions with 4-chlorophenol

We have examined the oxidative interactions of 4-chrlorophenol (hereafter 4-CP) with pyrite using Diffused Reflectance Fourier Transform Infra Red (DR-FTIR) spectroscopy. In order to enhance the 4-CP adsorption on pyrite, all experiments were conducted in gas phase under ambient atmospheric conditions. When traces of water are present, the pyrite oxidation has occurred both at Fe(II) and S2 sites forming FeOOH and S2O32− as intermediates. The 4-CP was chemisorbed onto newly developed FeOOH sites on pyrite with the concomitant release of H2O. Presence of FeOOH sites favored the H2O2 and OH radical production. The IR bands observed at 1170, 1203 and 1145 cm−1 evidenced for the presence of HSO4− and FeSO40 species in the vicinity.