Removal of guaiacol from cresylic acid feedstreams
US5171895A · kind A · utility
4Cited by
5References
7Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Mar 23, 1992 |
| Grant date | Dec 15, 1992 |
| Priority date | — |
| Expiry date | Mar 23, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C37/86
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Purification of cresylic acid by guaiacol removal from lignite-based feed as well as other naturally occurring sources of cresylic acid is accomplished by catalytic demethylation in the presence of an alumina catalyst. In the process of this invention, de-pitched, dephenolated creyslic acid is vaporized and passed over a high surface area, alumina catalyst at temperature ranges of between 350.degree. C. to 400.degree. C. and at vapor flow rates measured as liquid hourly space velocity (LHSV), of about 1 hr..sup.-1 to demethylate the guaiacol.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.