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:
Feb. 02, 1999
Filed:
Jun. 28, 1996
Robert Lewis Clarke, Orinda, CA (US);
Stephen Robert Clarke, Orinda, CA (US);
Electrochemical Design Associates, Inc., Berkeley, CA (US);
Abstract
A method and an apparatus for stripping ionic species from a porous material, such as concrete or soil, are presented. The ionic species include metals and complexes, and may include radioactive species. The contaminated medium can be in bulk or in particulate form and can be treated according to the invention in situ or in a batch container. In the method, a dc potential difference is established across the contaminated material over which an alternating current may be superimposed. Ionic species migrate within the contaminated material under the influence of the potential difference and dissolve in the electrolyte. The electrolyte can be protected from radiation degradation by use of a radioactive-resistant ion exchange material. Ionic species can be desorbed electrochemically from the electrolyte, allowing the electrolyte to be recycled for additional stripping of contaminated media. The recovered ionic species can be used as feedstock for other processes. The apparatus preferably includes an electrolytic material, means for electrochemically regenerating the electrolytic material, noncorroding electrodes capable of sustaining a current that is reverse of that which induces ionic species to migrate from contaminated medium and a power supply for establishing a potential difference across the contaminated material. Salt precipitation on the electrodes and within the medium are avoided. Neutral zones within the medium are also eliminated.