Chemical demineralization of a Turkish high ash bituminous coal

Demineralization of coal prior to usage offers some technical and cost-effective advantages since one of the most common limitations on coal processes results from high mineral matter content. In this work aimed at reducing the mineral matter content of high ash, low sulfur Amasra bituminous coal from Turkey, since physical methods were of limited use for reducing the ash content of bituminous coals, demineralization was studied using different acids (HF, HCl, HNO3 and H2SO4) alone and 0.5 N aqueous NaOH in combination with either one or two of the acids. The use of extraction with 0.5 N NaOH followed by leaching with 10% HCl was the optimum approach for the chemical cleaning of the coal under study, the maximum degree of demineralization obtained being 46.78%. (C) 1998 Elsevier Science B.V. All rights reserved.