Process for separating monochloroacetic acid and dichloroacetic acid via extractive distillation using an organic solvent
US9187400B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 3, 2013 |
| Grant date | Nov 17, 2015 |
| Priority date | — |
| Expiry date | Apr 3, 2033 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C51/46
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The present invention pertains to a process for separating monochloroacetic acid and dichloroacetic acid from one another via extractive distillation using (a) an extractive agent that is chemically stable and has a BF3 affinity of between 65 kJ/mole and 110 kJ/mole and (b) an organic solvent that is either an acid with a lowest pKa of between 3.0 and 6.5 or a base with a BF3 affinity of between 40 kJ/mole and 75 kJ/mole with the proviso that said BF3 affinity is lower than the BF3 affinity of the extractive agent, said organic solvent being chemically stable, and having a boiling point at atmospheric pressure of at least 468K, comprising the steps of (i) contacting a mixture comprising monochloroacetic acid and dichloroacetic acid with the extractive agent, (ii) distilling the mixture obtained in step (i) to obtain a monochloroacetic acid stream and a stream comprising dichloroacetic acid and the extractive agent, (iii) subjecting the stream comprising dichloroacetic acid and the extractive agent to a regeneration step, wherein the organic solvent is contacted with the mixture comprising monochloroacetic acid and dichloroacetic acid of step (i), or wherein the organic solvent is c…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.