Preparation of ammonium glyphosate using aqueous ammonium hydroxide in a liquid-solid reaction system
US5716903A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 3, 1997 |
| Grant date | Feb 10, 1998 |
| Priority date | — |
| Expiry date | Jan 3, 2017 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07F9/3813
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Solid N-phosphonomethylglycine or glyphosate acid is charged to a substantially closed system and then partially pre-dried as by continuously recirculating it through a hot air grinding/drying system. A cooled solution of ammonium hydroxide is then metered into and reacted with the partially dried glyphosate acid as it is being recirculated in a manner such that the moisture content of the reaction mass so formed is continuously decreased throughout the reaction. Following completion of the ammonium hydroxide addition, a powdered reaction mass/product having a moisture content of about 2 wt. % is formed. Significantly, at this stage, the ammonium glyphosate product is suitable for end use and it can be readily dissolved in water and immediately used as a herbicide or plant growth regulator. More importantly, however, this product is capable due to its highly sorptive character to be further formulated into a product exceptionally highly loaded with adjuvants and particularly surfactants.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.