MOSSBAUER ANALYSIS ON THE MICROWAVE—MAGNETIC DESULFURIZATION OF RAW COAL

翁斯灏

Nuclear Science and Techniques

pp.39-45

Published in print 01 Feb 1994

51701

The selective dielectric heating of microwave energy to convert a portion of each pyrite particle to moderately magnetic pyrrhotite has been suggested to enhance the magnetic separation of inorganic sulfur from coal. The results for Mossbauer analyses show that the considerable amount of pyrrhotite produced during microwave irradiation, carrying with it some of non-magnetic pyrite (unconverted), ferrous sulfate, and troilite, is completely removed from coal after magnetic separation. The optimum desulfurization efficiency can be attained by appropriately controlling the irradiation time to maximize the amount of pyrrhotite formed pyrite decomposition. Excessive irradiation would be disadvantageous for improving magnetic separation due to the further decomposition of pyrrhotite to antiferromagnetic troilite.

Coal desulfurizationMicrowave irradiationMagnetic separationMossbauer spectroscopy

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