Methods for removing impurities from coal including neutralization of a leaching solution

Abstract

A method for removing at least one impurity from coal is provided. The method comprises providing coal having a plurality of impurities and contacting the coal with a first leaching solution. The first leaching solution reacts with at least one of the impurities to produce one or more first products soluble in the first leaching solution. The method further comprises adding a neutralizing composition to the first leaching solution. The neutralizing composition reacts with the first leaching solution to form a precipitate. The method further comprises separating at least a portion of the first leaching solution from the coal and the precipitate and contacting the coal and the precipitate with a second leaching solution. The second leaching solution reacts with at least one of the impurities and the precipitate to form one or more second products and one or more third products, respectively, the second products and the third products being soluble in the second leaching solution. The method further comprises separating at least a portion of the second leaching solution from the coal.

Dependencies are inferred from the claim text.