Solubilities of elements on in-stack suspended particles from a municipal incinerator

Previous studies have shown that small particles emitted from waste incinerators are enriched in many elements. e.g. Na, Cl, Br, Cu, Zn, As, Ag, Cd, In, Sn, Sb, W and Pb. Experiments were done to determine the water solubility of elements on in-stack cascade-impactor and whole-filter samples collected at a municipal incinerator. Na, Cs. K, Zn, Cl, Br, Cd and Pb were all very soluble. Solubilities range from 63% for Zn to 100% for Cl, and increase with decreasing particle size. Other elements associated with small particles and those on larger particles, i.e. Cu, As. In, Sn, Sb, W, Au, Al, Ti, Sc, La. V, Cr. 17 e, Mn, Co and Se are mostly insoluble (< 20%). Calcium was very soluble (73%) and the solubility of Ag varied from < 2 to 57%. It was determined, using scanning electron microscopy, that small particles are composed of a rather homogeneous mixture of chloride salts of the major elements Na, K, Zn and Pb.