Process for purifying glyoxal
US4006189A · kind A · utility
2Cited by
2References
6Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 11, 1974 |
| Grant date | Feb 1, 1977 |
| Priority date | — |
| Expiry date | Jun 11, 1994 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C45/85
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Crude glyoxal solutions obtained for example by the oxidation of acetaldehyde with nitric acid are purified by removing volatile acids followed by neutralization. Thereafter, the glyoxal is converted into a glyoxal glyoxal-di-(alkylhemiacetal) with an alcohol containing 1 to 3 carbon atoms with water removal during the conversion. After separating salts and other impurities, the glyoxal-di-(alkylhemiacetal) is hydrolyzed with water at elevated temperatures to yield pure glyoxal hydrate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.