Process for the purification of benzene that comprises two permeation stages
US5905182A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 23, 1997 |
| Grant date | May 18, 1999 |
| Priority date | — |
| Expiry date | Sep 23, 2017 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C7/144
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A mixture that contains benzene, other aromatic hydrocarbons and paraffinic hydrocarbons and/or naphthenic hydrocarbons that have 5 to 10 carbon atoms undergoes distillation in a first column, producing a distillate and a residue; a phase is drawn off laterally from the first distillation column, preferably at a point on the column where the benzene content is essentially at maximum where the toluene content is low; the phase that is drawn off is sent toward a first permeation stage, which produces a permeate that is enriched with benzene and a retentate; at least a portion of said retentate is recycled toward said first distillation column; the benzene-enriched permeate from stage (3) is sent to a second distillation column, from which the purified benzene comes out at the bottom and a distillate vapor comes out at the top; the distillate vapor is condensed, and the condensed distillate is sent at least in part to a second permeation stage; in said second permeation stage, a permeate that is also enriched in benzene and a retentate are separated; the permeate is recycled to the second distillation column; and the retentate is recycled toward the inlet of the first permeation stage…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.