Process for co-producing para-xylene and metaxylene, comprising two separation steps
US6838588B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 29, 2002 |
| Grant date | Jan 4, 2005 |
| Priority date | — |
| Expiry date | Jun 26, 2023 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C7/13
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process is described for co-producing metaxylene and paraxylene from a hydrocarbon feed comprising two separation steps. The first step of the process is a counter-current simulated moving bed system in a chromatographic column containing at least five zones, comprising injecting the feed and injecting a desorbent and delivering an extract, a raffinate and an intermediate raffinate either continuously or discontinuously. The extract is distilled to obtain a paraxylene with a purity of at least 99.7%. The raffinate, which is richer in metaxylene, is distilled to extract the desorbent and injected into a counter-current simulated moving bed continuously delivering an extract and a raffinate. One of these two streams is enriched in metaxylene. The most metaxylene-rich stream is distilled to obtain metaxylene with a purity of more than 99%.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.