Process for co-production of paraxylene, metaxylene and/or orthoxylene
US6841714B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 20, 2002 |
| Grant date | Jan 11, 2005 |
| Priority date | — |
| Expiry date | Jul 3, 2023 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C7/13
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process for co-production of paraxylene, metaxylene and/or orthoxylene from a hydrocarbon feedstock (1) that comprises [1] a separation stage of the feedstock in a simulated moving bed in a chromatographic column (9) that contains a number of beds of an adsorbent, interconnected in a loop, is described, whereby said column comprises an injection (3) of the feedstock, a draw-off (10) of an extract that consists of paraxylene and desorbent, an intermediate fraction (11) (extract or raffinate) that contains ethylbenzene, and a raffinate (12) that contains a mixture of metaxylene and orthoxylene that is virtually free of ethylbenzene and paraxylene and [2] a crystallization stage (27) of the metaxylene and/or orthoxylene fraction. Upstream from the adsorption zone and/or upstream from the crystallization zone, it is possible to distill the entering mixture to produce an orthoxylene-enriched fraction at the bottom and a metaxylene-enriched fraction at the top.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.