Method for removing polychlorinated dibenzodioxins and polychlorinated dibenzofurans from secondary fibers using supercritical CO.sub.2 extraction
US5009745A · kind A · utility
6Cited by
20References
14Claims
0Family size
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Key dates
| Filing date | Oct 12, 1990 |
| Grant date | Apr 23, 1991 |
| Priority date | — |
| Expiry date | Oct 12, 2010 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02W30/64
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A process for removing PCDD's and PCDF's from cellulose-containing fibers such as waste paper is provided. The process comprises contacting the fibers with supercritical or near supercritical carbon dioxide for a period of time sufficient to extract a substantial portion of the PCDD's and PCDF's without substantially damaging the fibers. Extraction efficiencies of greater than 95% have been achieved with the technique.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.