Gamma Irradiation of Pyrite in Egyptian Coal as Studied by Means of Mössbauer Spectroscopy at Room Temperature

Abstract

A well characterized coal sample from Egypt was irradiated using ⁶⁰Co source for different dwell times starting from 10 to 100 h in the first experiment and from 7 to 28 days for the second one. The constant dose rates of both were 9.12 and 7.61 Gray/min, respectively. Mossbauer results obtained from the first irradiation process have shown oxidation of pyrite to jarosite. While ferrous sulfates resulted from pyrite oxidation is clearly evidenced in the irradiated coals from 7 to 28 days. Gamma irradiation as a method for coal desulphurization is discussed.

Keywords:

• coal
• irradiation
• pyrite
• Mossbauer spectroscopy

Notes

^aEM-70—The numerical data reprint from Ahmed et al., 2003.

^bEM-70—The numerical data obtained from the present work.

^c%: Relative area

^dPyrite: FeS₂

^eSzomolnokite: (FeSO₄.H₂O).

^aIn hours and constant dose rate equal to 9.12 Gray/min.

^b%: Relative area

^cPyrite: FeS₂

^dFe³⁺ in jarosite: (Na, K) Fe₂ (SO₄)₃.nH₂O).

^aIn days and constant dose rate equal to 7.61 Gray/min.

^b%: Relative area

^cPyrite: FeS₂

^dFe³⁺ in jarosite: (Na, K) Fe² (SO₄)₃.nH₂O).