Use of a supplemental promoter in conjunction with a carbon-supported, noble-metal containing catalyst in liquid phase oxidation reactions
US6586621B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 21, 2000 |
| Grant date | Jul 1, 2003 |
| Priority date | — |
| Expiry date | Dec 21, 2020 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01J37/0205
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
This invention relates to the use of a supplemental promoter in conjunction with a noble-metal-containing catalyst comprising a carbon support in catalyzing liquid phase oxidation reactions, a process for making of an improved catalyst comprising such a supplemental promoter, and an improved catalyst comprising such a supplemental promoter.In a particularly preferred embodiment, a supplemental promoter (most preferably bismuth or tellurium) is used in conjunction with a noble-metal-containing catalyst comprising a carbon support in a liquid phase oxidation process wherein N-(phosphonomethyl) iminodiacetic acid (i.e., “PMIDA”) or a salt thereof is oxidized to form N-(phosphonomethyl) glycine (i.e., “glyphosate”) or a salt thereof. The benefits of such a process include increased oxidation of the formaldehyde and formic acid by-products, and, consequently, decreased final concentrations of those by-products as well as other undesirable by-products, most notably N-methyl-N-(phosphonomethyl) glycine (i.e., “NMG”).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.