Removal of mercury heavy metal values employing sulfur trioxide

Abstract

Heavy metal values can be removed and separated from a substance having a suitable amount of the heavy metal values by contacting the substance with a fluid containing sulfur trioxide to prepare a corresponding heavy metal sulfate, which is followed by leaching the sulfate therefrom and separating the leached sulfate. For example, mercury metal, oxide or sulfide, or methyl mercury, such as can be found in used fluorescent lamps and household batteries, in industrial flue sands, fly ash, contaminated soils, etc., can be removed by contact of crushed lamps or batteries, samples of the flue sands, fly ash, or contaminated soils, etc., with a mixture of sulfur trioxide in air to form mercuric sulfate, which is leached with a suitable leaching agent such as water, aqueous hydrochloric acid, hot dilute sulfuric acid, or concentrated sodium chloride solution, and sequestered by use of an ion exchange resin or precipitated as sulfides for further isolation of mercury value.

Dependencies are inferred from the claim text.