Trimethylolpropane color improvement
US8354561B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 22, 2010 |
| Grant date | Jan 15, 2013 |
| Priority date | — |
| Expiry date | Jul 5, 2031 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C29/88
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The present invention provides a process for improving the color of trimethylolpropane which comprises the steps of a) supplying a crude, aqueous base solution of trimethylolpropane, containing color causing impurities, and having a pH of less than about 9; b) contacting said base solution with an alkaline material for a period of time sufficient to increase the pH of said base solution to greater than 11 and at a sufficient temperature to allow the color causing impurities to react with said alkaline material; c) cooling the resulting solution from step (b) for a sufficient period of time; d) contacting said base solution of step (c) with an organic acid for a sufficient period of time to lower the pH thereof to less than about 9.5; e) extracting the trimethylolpropane from said base solution of step (d) with an organic solvent; f) separating the trimethylolpropane from said organic solvent; and g) purifying said trimethylolpropane from step f) to form a trimethylolpropane having a phthalic color of less than 0.20 and an acid wash color of less than 8.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.