초록 ▼

In general the present invention relates to a continuous process for manufacturing (N-phosphonomethyl) glycine, glyphosate, by the catalyzed oxidation of N-phosphonomethyliminodiacetic acid. Glyphosate can be provided in high yield and in a cost efficient process by minimizing the competing side rea

In general the present invention relates to a continuous process for manufacturing (N-phosphonomethyl) glycine, glyphosate, by the catalyzed oxidation of N-phosphonomethyliminodiacetic acid. Glyphosate can be provided in high yield and in a cost efficient process by minimizing the competing side reactions and by-products. The process includes conducting the oxidation reaction and selecting an appropriate catalyst to maximize the rate of the oxidation of N-phosphonomethyliminodiacetic acid while at the same time minimizing the rate of oxidation of glyphosate in the same reaction.

대표청구항 ▼

1. A continuous process for the production of glyphosate, said process comprising:contacting N-phosphonomethyliminodiacetic acid with molecular oxygen in the presence of a carbon catalyst supported in a fixed bed reactor under conditions which oxidize N-phosphonomethyliminodiacetic acid to glyphosat

1. A continuous process for the production of glyphosate, said process comprising:contacting N-phosphonomethyliminodiacetic acid with molecular oxygen in the presence of a carbon catalyst supported in a fixed bed reactor under conditions which oxidize N-phosphonomethyliminodiacetic acid to glyphosate and oxidize glyphosate to (aminomethyl)phosphonic acid; and selecting a carbon catalyst for use in the process whereby a ratio of a rate constant of reaction of glyphosate with molecular oxygen to a rate constant of reaction of N-phosphonomethyliminodiacetic acid with molecular oxygen is less than about 0.017. 2. The process of claim 1, wherein the ratio of the rate constant of the reaction of glyphosate with molecular oxygen to the rate constant of the reaction of N-phosphonomethyliminodiacetic acid with molecular oxygen is less than about 0.008.3. The process of claim 1, wherein the ratio of the rate constant of the reaction of glyphosate with molecular oxygen to the rate constant of the reaction of N-phosphonomethyliminodiacetic acid with molecular oxygen is less than about 0.004.4. The process of claim 1 wherein said contacting is performed at a temperature level of at least about 75° C.5. The process of claim 1 wherein the carbon catalyst that is selected exhibits a peroxide decomposition factor of greater than about 1 hour/(g/cm3).6. The process of claim 1 wherein the carbon catalyst that is selected exhibits a peroxide decomposition factor of greater than about 0.8 hour/(g/cm3).7. The process of claim 1 wherein the carbon catalyst that is selected has an average particle size of between about 150 and about 3000 micrometers.8. The process of claim 7 wherein the carbon catalyst that is selected has an average particle size of between about 250 and about 1000 micrometers.9. The process of claim 7 wherein the carbon catalyst that is selected exhibits a peroxide decomposition factor of greater than about 8 hour/(g/cm3).10. The process of claim 1 wherein N-phosphonomethyliminodiacetic acid is provided as a saturated aqueous solution.11. The process of claim 1 wherein N-phosphonomethyliminodiacetic acid is provided in a concentration of between about 2 wt % and about 10 wt% in an aqueous solution.12. The process of claim 1 wherein the process is conducted at a pressure of between about 3.5 atm and about 20 atm.13. The process of claim 1 wherein greater than about 95 molar % of the N-phosphonomethyliminodiacetic acid is consumed.14. The process of claim 13 wherein the carbon catalyst that is selected exhibits a peroxide decomposition factor of greater than about 1 hour/(g/cm3).15. The process of claim 14 wherein the carbon catalyst that is selected exhibits a peroxide decomposition factor of greater than about 8 hour/(g/cm3).16. The process of claim 1 wherein the N-phosphonomethyliminodiacetic acid and the molecular oxygen are combined in a reaction mixture, said mixture provided to sequentially flow through two or more fixed bed reactors connected in series.17. A continuous process for the production of glyphosate, said process comprising:contacting N-phosphonomethyliminodiacetic acid with molecular oxygen in the presence of a carbon catalyst supported in a fixed bed reactor under conditions which oxidize N-phosphonomethyliminodiacetic acid to glyphosate in greater than about 93% molar yield and oxidize glyphosate to (aminomethyl)phosphonic acid; and selecting a carbon catalyst for use in the process whereby a ratio of a rate constant of reaction of glyphosate with molecular oxygen to a rate constant of reaction of N-phosphonomethyliminodiacetic acid with molecular oxygen is less than about 0.017. 18. A continuous process for the production of glyphosate, said process comprising:contacting N-phosphonomethyliminodiacetic acid with molecular oxygen in the presence of a carbon catalyst supported in a fixed bed reactor under conditions which oxidize N-phosphonomethyliminodiacetic acid to glyphosate and oxidize glyphosate to (aminomethyl)phosphonic acid; and conducting the process whereby a ratio of a rate constant of reaction of glyphosate with molecular oxygen to a rate constant of reaction of N-phosphonomethyliminodiacetic acid with molecular oxygen is less than about 0.017. 19. A continuous process for the production of glyphosate, said process comprising:contacting N-phosphonomethyliminodiacetic acid with molecular oxygen in the presence of a carbon catalyst supported in a fixed bed reactor under conditions which oxidize N-phosphonomethyliminodiacetic acid to glyphosate in greater than about 93% molar yield and oxidize glyphosate to (aminomethyl)phosphonic acid; and conducting the process whereby a ratio of a rate constant of reaction of glyphosate with molecular oxygen to a rate constant of reaction of N-phosphonomethyliminodiacetic acid with molecular oxygen is less than about 0.017.