Low energy carbonylation process
US6657078B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 7, 2001 |
| Grant date | Dec 2, 2003 |
| Priority date | — |
| Expiry date | Jun 5, 2021 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C51/47
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A low energy process for producing acetic acid by the carbonylation of methanol is disclosed. The process involves a rhodium-catalyzed system operated at less than about 14% water utilizing up to 2 distillation columns. The process is preferably controlled such that the product stream has a low level of propionic acid impurity and the level of aldehyde impurities is minimized by way of aldehyde removal or minimizing aldehyde generation. The level of iodides is controlled by contacting the product, at elevated temperatures, with ion exchange resins. In preferred embodiments, at least one silver or mercury exchanged macroreticular strong acid ion exchange resin is used to purify the product. The high temperature treatment provides the added benefit of controlling the Color Value (Pt—Co units) of the product stream.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.