Elution of Ti during Solvent Extraction of Coal and the Transformation of Eluted Ti upon Combustion.

This article discusses the use of solvents to remove coal ash and generate a clean form of coal. The presence of nanoscale titanium compounds, including titanium dioxide, in this clean coal is noted as a concern because of its negative environmental impact. The Argonne premium coal samples (APCS) Illinois No. 6 (IL) bituminous coal and wyodak-anderson (WY) subbituminous coal are used in this research. The effects of acetic and sulphuric acids as solvents for coal are discussed. The different qualities of titanium compounds in different types of coal are described. The levels of titanium speciation found in these coals is discussed.