Effect of clay content on surface characteristics of coal ground under different conditions

ABSTRACT The surface characteristics of a coal with a kaol in content of 7% have been studied. The coal has been either wet or dry ground, with and without an additive. All the products have been examined by XPS and IR spectrometry. The results show that the wet and dry grinding lead to different surface content of the clay species, while the additive seems to have negligible effect. Wet grinding leads to a concentration of kaolin on the coal surface that is 3 times higher than in the case of the dry ground sample and 7 times higher than in the bulk.