Abstract: In a method of controlling air pollution, a combustion gas is passed through a slurry of an alkaline-earth metal sulfide and a redox buffer (e.g., a phosphate), preferably in combination with an alkaline-earth metal carbonate and/or hydroxide. A composition for removing a heavy metal from a combustion gas is also provided, as an aerosolized, aqueous dispersion or slurry of an alkaline-earth metal sulfide and a buffering agent. A solid residue of the air pollution control process is also described.

Abstract: In a method of controlling air pollution, a combustion gas is passed through a slurry of an alkaline-earth metal sulfide and a redox buffer (e.g., a phosphate), preferably in combination with an alkaline-earth metal carbonate and/or hydroxide. A composition for removing a heavy metal from a combustion gas is also provided, as an aerosolized, aqueous dispersion or slurry of an alkaline-earth metal sulfide and a buffering agent. A solid residue of the air pollution control process is also described.

Abstract: An improved paint stripper is provided and comprises at least one paint-stripping agent modified with at least one heavy metal remediation agent. Optionally, one or more viscosity-modification agents, dispersants, or other additive is also included. The invention also provides a kit for making a heavy metal-remediating paint stripper, comprising a vessel containing a paint-stripping agent and a dissolvable packet containing a remediation agent. To use the kit, a painter or other laborer opens the vessel containing the paint-stripping agent and deposits therein the packet containing the remediation agent. The packet dissolves, thereby releasing the remediation agent into the stripping agent.

Abstract: The invention provides polymeric matrices and films comprising fixation reagents that are capable of reacting with solubilized metals to form less soluble metal compounds. The fixation reagenst may include inorganic sulfides and phosphates, as well as adsorbents. The polymeric matrices may be comprised of polyvinyl alcohols and polyvinyl acetates. In some embodiments, the polymeric matrix is selected to be at least as soluble as the selected fixation reagent, particularly under the conditions in which the matrix is expected to come into contact with the solublized metal.

Abstract: A process for treating contaminated waste to stabilize environmentally harmful heavy metal. The contaminated waste is contacted with a mixture of (i) inorganic sulfide, (ii) calcium phosphate to prevent oxidation of the sulfide and (iii) calcium carbonate, the last acting as a base. Water is added to enhance mass transfer during the mixing. The calcium carbonate may be mixed with calcium oxide, to provide an additional base.

Abstract: A process for treating contaminated waste to stabilize environmentally harmful heavy metals. The waste is contacted with a mixture of a sulfide, preferably calcium sulfide, an inorganic phosphate, which prevents oxidation of sulfide, and a base that at least includes calcium hydroxide. The process stabilizes harmful, heavy metal materials in the waste but avoids the prior art disadvantage of emitting hydrogen sulfide.