Production of para-xylene from an effluent from paraselective toluene disproportionation using a crystallization process combined with simulated moving bed adsorption
US6060634A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 12, 1998 |
| Grant date | May 9, 2000 |
| Priority date | — |
| Expiry date | Aug 12, 2018 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C7/14
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Para-xylene is produced from a paraselective toluene disproportionation reactor, effluent (3) is distilled to eliminate toluene and benzene in at least 2 distillation columns (C1), (C2), and the xylenes (8) are crystallized at least once (10) at between +10.degree. C. and -30.degree. C. The separated mother liquor (14) is adsorbed on a zeolitic sieve in the presence of toluene in a simulated moving bed (15). This latter produces a raffinate (16) containing toluene which is depleted in para-xylene which is distilled in a distillation column (C4), and an extract which is enriched in para-xylene and contains toluene, which is recycled to columns (C1, C2). The para-xylene crystals are purified by washing with toluene and distillation or by partial melting (30) followed by washing with molten high purity para-xylene.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.