Improved method for preparing glyphosate by catalytic oxidation of N-(phosphonomethyl) iminodiacetic acid through oxygen-rich gas

Abstract

The invention provides an improved method for preparing glyphosate by catalytically oxidizing N-(phosphonomethyl) iminodiacetic acid with oxygen-rich gas. The method comprises the following steps: selecting N-(phosphonomethyl) iminodiacetic acid (PMIDA) as the raw material, active carbon as a catalyst, and an oxygen-rich gas as an oxidant, adding N-(phosphonomethyl) iminodiacetic acid, the activecarbon and water into a high-pressure reaction kettle at a certain ratio, introducing the oxygen-rich gas to carry out oxidation reaction, adding filter cake after the oxidation reaction into a saturated glyphosate solution to fully dissolve glyphosate crystals as much as possible, and filtering while the solution is hot to obtain glyphosate. The method can improve the solubility of glyphosate and further improve the yield of the dry product, and can solve the bumping problem existing in the active carbon separation process at high temperature, thereby improving the safety of the production and effectively separating glyphosate and the active carbon. The method has the advantages of simple operation, easy recovery and utilization of the catalyst, reduced energy consumption, environmental protection, low production cost, etc.

Description

technical field

[0001] The invention belongs to the field of glyphosate preparation, and in particular relates to an improved method for preparing glyphosate by catalytic oxidation of high-concentration diglyphosate with oxygen-enriched gas. Background technique

[0002] Glyphosate (glyphosate, N-(phosphonomethyl)-glycine) is a high-efficiency, broad-spectrum, low-toxicity, and safe organophosphate herbicide, which is very effective in the control of perennial deep-rooted weeds. Forestry, animal husbandry, gardening and other aspects are widely used. Due to the expansion of the global planting of genetically modified crops, as well as the recovery and modernization of global agriculture, especially in developing countries, the demand for glyphosate has grown rapidly, and it has become the largest and fastest-growing pesticide variety in the world.

[0003] At present, there are many techniques for preparing glyphosate, mainly including glycine method (Gly method) and iminod...

Examples

Embodiment 1

[0028] With 98% diglyphosate (PMIDA) former powder as raw material, activated carbon as catalyst, oxygen-enriched as oxidant, at first 300g diglyphosate, 400g pure water, 50g activated carbon catalyst are put into stainless steel autoclave, stir evenly, Raise the temperature, open the air intake control valve, feed the oxygen-enriched gas with an oxygen content of 80% at an average speed, control the reaction pressure and temperature, cool the reacted feed liquid, and collect the mixed filter cake containing glyphosate and activated carbon Put it into the mixed solution of 1800ml PMG saturated solution and 1200ml ethylene glycol solvent, then put it into the normal pressure reactor, stir slowly and raise the temperature to 105℃, so that the glyphosate crystals are fully dissolved, and then filter while it is hot. The filter bag is used for filtration. After the filtration, the activated carbon in the filter bag is recovered, washed with a small amount of water, and dried for la...

Embodiment 2

[0031] With 98% diglyphosate (PMIDA) former powder as raw material, activated carbon as catalyst, oxygen-enriched as oxidant, at first 300g diglyphosate, 400g pure water, 50g activated carbon catalyst are put into stainless steel autoclave, stir evenly, Raise the temperature, open the air intake control valve, feed pure oxygen gas at an even speed, control the reaction pressure and temperature, cool the reacted feed liquid, and put the collected mixed filter cake containing glyphosate and activated carbon into 1500ml PMG saturated solution and 1500ml glycerol (glycerol) solvent mixed solution, then put it into the normal pressure reactor, slowly stir and heat up to 110°C, so that the glyphosate crystals are fully dissolved, and then filter while it is hot, using the built-in filter bag of the reactor for filtration. Filtration. After the filtration, the activated carbon in the filter bag is recovered, washed with a small amount of water, and dried for later use.

[0032] Stir ...

Embodiment 3

[0034]With 98% diglyphosate (PMIDA) former powder as raw material, activated carbon as catalyst, rich oxygen as oxidant, at first 200g diglyphosate, 300g pure water, 35g activated carbon catalyst are put into stainless steel autoclave, stir evenly, Raise the temperature, open the air intake control valve, feed the oxygen-enriched gas with an oxygen content of 98% at an average speed, control the reaction pressure and temperature, cool the reacted feed liquid, and collect the mixed filter cake containing glyphosate and activated carbon Put it into the mixed solution of 1200ml PMG saturated solution and 800ml ethylene glycol solvent, then put it into the normal pressure reactor, stir slowly and raise the temperature to 108°C to fully dissolve the glyphosate crystals, and then filter while it is hot. The filter bag is used for filtration. After the filtration, the activated carbon in the filter bag is recovered, washed with a small amount of water, and dried for later use.

[003...

technical field

[0001] The invention belongs to the field of glyphosate preparation, and in particular relates to an improved method for preparing glyphosate by catalytic oxidation of high-concentration diglyphosate with oxygen-enriched gas. Background technique

[0002] Glyphosate (glyphosate, N-(phosphonomethyl)-glycine) is a high-efficiency, broad-spectrum, low-toxicity, and safe organophosphate herbicide, which is very effective in the control of perennial deep-rooted weeds. Forestry, animal husbandry, gardening and other aspects are widely used. Due to the expansion of the global planting of genetically modified crops, as well as the recovery and modernization of global agriculture, especially in developing countries, the demand for glyphosate has grown rapidly, and it has become the largest and fastest-growing pesticide variety in the world.

[0003] At present, there are many techniques for preparing glyphosate, mainly including glycine method (Gly method) and iminod...

Examples

Embodiment 1

[0028] With 98% diglyphosate (PMIDA) former powder as raw material, activated carbon as catalyst, oxygen-enriched as oxidant, at first 300g diglyphosate, 400g pure water, 50g activated carbon catalyst are put into stainless steel autoclave, stir evenly, Raise the temperature, open the air intake control valve, feed the oxygen-enriched gas with an oxygen content of 80% at an average speed, control the reaction pressure and temperature, cool the reacted feed liquid, and collect the mixed filter cake containing glyphosate and activated carbon Put it into the mixed solution of 1800ml PMG saturated solution and 1200ml ethylene glycol solvent, then put it into the normal pressure reactor, stir slowly and raise the temperature to 105℃, so that the glyphosate crystals are fully dissolved, and then filter while it is hot. The filter bag is used for filtration. After the filtration, the activated carbon in the filter bag is recovered, washed with a small amount of water, and dried for la...

Embodiment 2

[0031] With 98% diglyphosate (PMIDA) former powder as raw material, activated carbon as catalyst, oxygen-enriched as oxidant, at first 300g diglyphosate, 400g pure water, 50g activated carbon catalyst are put into stainless steel autoclave, stir evenly, Raise the temperature, open the air intake control valve, feed pure oxygen gas at an even speed, control the reaction pressure and temperature, cool the reacted feed liquid, and put the collected mixed filter cake containing glyphosate and activated carbon into 1500ml PMG saturated solution and 1500ml glycerol (glycerol) solvent mixed solution, then put it into the normal pressure reactor, slowly stir and heat up to 110°C, so that the glyphosate crystals are fully dissolved, and then filter while it is hot, using the built-in filter bag of the reactor for filtration. Filtration. After the filtration, the activated carbon in the filter bag is recovered, washed with a small amount of water, and dried for later use.

[0032] Stir ...

Embodiment 3

[0034]With 98% diglyphosate (PMIDA) former powder as raw material, activated carbon as catalyst, rich oxygen as oxidant, at first 200g diglyphosate, 300g pure water, 35g activated carbon catalyst are put into stainless steel autoclave, stir evenly, Raise the temperature, open the air intake control valve, feed the oxygen-enriched gas with an oxygen content of 98% at an average speed, control the reaction pressure and temperature, cool the reacted feed liquid, and collect the mixed filter cake containing glyphosate and activated carbon Put it into the mixed solution of 1200ml PMG saturated solution and 800ml ethylene glycol solvent, then put it into the normal pressure reactor, stir slowly and raise the temperature to 108°C to fully dissolve the glyphosate crystals, and then filter while it is hot. The filter bag is used for filtration. After the filtration, the activated carbon in the filter bag is recovered, washed with a small amount of water, and dried for later use.

[003...

Images