The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 30, 2001
Filed:
Jul. 06, 2000
Dhiraj Pal, Chicago Heights, IL (US);
Karl W. Yost, Crete, IL (US);
Sevenson Environmental Services, Inc., Niagara Falls, NY (US);
Abstract
The present invention discloses a method of forming phosphate mineral species of the apatite family, and the mineral species thus formed, by contacting soil or solid waste material containing leachable lead with a combination of a sulfate reagent that includes one or more reactive sulfate ions and a phosphate supplying reagent that includes one or more reactive phosphate ions. The mineral species are stable, substantially water insoluble and non-leachable under normal environmental conditions. The sulfate reagent is sulfuric acid or alum in liquid or powder form. The phosphate supplying reagent is phosphoric acid, trisodium phosphate, potassium phosphate, mono basic calcium phosphate or dibasic calcium phosphate. In a preferred embodiment, the phosphate supplying reagent is phosphoric acid and the sulfate reagent is sulfuric acid or liquid alum.