Patent Number: 6,309,337

Title: Method of forming an insoluble phosphate mineral species

Abstract: The present invention discloses a method of forming phosphate mineralspecies of the apatite family, and the mineral species thus formed, bycontacting soil or solid waste material containing leachable lead with acombination of a sulfate reagent that includes one or more reactivesulfate ions and a phosphate supplying reagent that includes one or morereactive phosphate ions. The mineral species are stable, substantiallywater insoluble and non-leachable under normal environmental conditions.The sulfate reagent is sulfuric acid or alum in liquid or powder form. Thephosphate supplying reagent is phosphoric acid, trisodium phosphate,potassium phosphate, mono basic calcium phosphate or dibasic calciumphosphate. In a preferred embodiment, the phosphate supplying reagent isphosphoric acid and the sulfate reagent is sulfuric acid or liquid alum.

Inventors: Pal; Dhiraj (Chicago Heights, IL), Yost; Karl W. (Crete, IL)


International Classification:

Expiration Date: 10/32013