Preparation of solid ammonium glyphosate using organic solvent in extraction
US7435847B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 4, 2003 |
| Grant date | Oct 14, 2008 |
| Priority date | — |
| Expiry date | May 2, 2025 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07F9/3813
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A method of preparing ammonium glyphosate suitable for preparation of water-soluble solid ammonium glyphosate formulation by an extraction with organic solvent in a gas-liquid-solid phase system, which comprises adding glyphosate and water into a reactor with a stirer, introducing ammonia to carry out the reaction, an aqueous solution of ammonium glyphosate is formed after the reaction is completed; adding a water-soluble organic solvent such as methanol and/or ethanol and/or methylal to decrease the solubility of the ammonium glyphosate in the system, thereby crystallizing out ammonium glyphosate; and filtering in suction or further oven-drying to obtain the solid ammonium glyphosate. The organic solvent may be recovered and reused by rectifying or distilling, the remainder residue may be returned to the reaction procedure or used in the preparation of the aqueous formulation of ammonium glyphosate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.