Process for the separation of phenol from phenol-containing streams from the preparation of Bisphenol A
US7301056B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 2005 |
| Grant date | Nov 27, 2007 |
| Priority date | — |
| Expiry date | Jun 28, 2025 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C37/86
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A continuous process for the separation of phenol is disclosed. The process includes (a) feeding a stream of material, produced while preparing bisphenol A by reacting phenol with acetone, into a distillation column containing at least 5 theoretical separation stages, b) distilling-off the phenol as a top product and discharging from the column a bottom product containing secondary components, c) continuously introducing a portion of the bottom product into a dwell-time container operating at process parameters sufficient to cause, in the presence of an acidic catalyst, at least partial isomerization of the secondary components to form an isomerized product and d) introducing the isomerized product to the distillation column. The introducing of the bottom product is at a rate that is more than 30% of the rate of feeding of the stream at temperatures greater than 190° C. and hydrodynamic dwell time of at least 120 minutes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.