Patent · US Expired

Process for production of paraxylene comprising a high-temperature crystallization with at least one stage and a partial melting of the crystals

US6111161A · kind A · utility

10Cited by
6References
32Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 21, 1997
Grant dateAug 29, 2000
Priority date
Expiry dateJul 21, 2017

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07C7/14
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

A process for production of paraxylene from a charge containing C7-C9 aromatic hydrocarbons in which a first fraction is enriched to at least 30% weight with paraxylene and this fraction is purified by at least one high-temperature crystallization in at least one crystallization zone. Said first fraction is crystallized in a crystallization zone at high temperature T1 and advantageously between +10 and -25.degree. C., crystals in suspension in a mother liquor are recovered, the crystals are separated from the mother liquor in at least a first separation zone, the crystals obtained are partially melted in at least a zone for partial melting and a suspension of crystals is recovered, the crystals in suspension are separated and washed in at least one separation and washing zone and pure paraxylene crystals and washing liquor are recovered, and pure crystals are optionally completely melted and a liquid stream of melted paraxylene is collected.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.