Abstract: Unwanted settling in a composition comprising a suspension of fine particles of coal in fuel oil is eliminated or substantially reduced by adding an effective amount of a fatty acid ester of a polyoxypropylene-polyoxyethylene copolymer. The fatty acid has about 12 to 22 carbon atoms in the acyl group. The polyoxyethylene groups and polyoxypropylene groups have a total molecular weight of about 500 to 2000 and contain 0 to about 60 percent by weight polyoxyethylene groups.

Abstract: Unwanted settling in a composition comprising a suspension of fine particles of coal in fuel oil is eliminated or substantially reduced by adding an effective amount of a polyoxypropylene-polyoxyethylene copolymer which corresponds to the formula:Y[(C.sub.2 H.sub.4 O).sub.m (C.sub.3 H.sub.6 O).sub.n H].sub.xwherein Y is the residue of an organic compound having from about 1 to 6 carbon atoms and containing x reactive hydrogen atoms in which x has a value of at least one, m has a value such that the oxyethylene content of the molecule is from about 10 to 40 weight percent and n has a value such that the total molecular weight of the polyoxyalkylene groups is from about 2000 to 6000.