Immobilization of metal contaminants from a liquid to a solid medium
US5495064A · kind A · utility
15Cited by
5References
14Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 4, 1994 |
| Grant date | Feb 27, 1996 |
| Priority date | — |
| Expiry date | May 4, 2014 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA62D2101/43
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A method for the immobilization of heavy metal contaminant from a liquid medium containing sulfuric acid and one or more acids of phosphorus, for example in the treatment of acid raffinates generated during the purification of phosphoric acid. The method includes the steps of (i) neutralizing the liquid medium with a stoichiometric excess of an alkaline earth metal oxide to form agglomerates, and (ii) treating the agglomerates with water to form a solid cementitious material wherein the heavy metal contaminants are substantially chemically isolated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.