Efficient synthesis process of glufosinate-ammonium intermediate

Abstract

The invention discloses an efficient synthesis process of a glufosinate-ammonium intermediate, and belongs to the technical field of synthesis of organic phosphorus compound intermediates, foamy copper particles are etched by nitric acid, so that the surfaces of the foamy copper particles become rougher, the surface of the foamy copper is subjected to chemical nickel plating treatment, a nickel layer with anti-corrosion capability is generated on the surface, and secondary etching treatment is performed by urea, so that the foamy copper particles are more uniform. A layer of tightly contacted nickel hydroxide layer grows on the surface, the surface has abundant hydroxyl (-OH) functional groups, a porous organic framework with adsorption capacity is generated on the surface in situ through hydroxyl, the organic framework is carbonized on the surface, high-strength nickel-plated foamy copper with the surface wrapped by a carbon layer is obtained, and through the residual hydroxyl groups on the surface, the nickel-plated foamy copper can be effectively adsorbed. And a metal framework with catalytic activity is generated on the surface in situ by combining with carboxyl of p-hydroxybenzoic acid, so that the catalytic efficiency of the catalyst is improved, the service life of the catalyst is prolonged, the productivity of the glufosinate-ammonium intermediate is improved, and the utilization rate of phosphorus trichloride is increased.

Description

Technical Field

[0001] The invention belongs to the technical field of synthesis of organic phosphorus compound intermediates, and in particular relates to a high-efficiency synthesis process of a glufosinate-ammonium intermediate. Background Art

[0002] Glufosinate is an organophosphorus herbicide developed and produced by Hoechst in the 1980s. It has the characteristics of low toxicity, high efficiency, and non-selectivity (killing). Since the domestic sales and use of paraquat aqueous solution was stopped on July 1, 2016, glufosinate has become a hot alternative for pesticide manufacturers. Methyl phosphonic acid dichloride is an important intermediate for the synthesis of organophosphorus compounds and is widely used. Hundreds of organophosphorus compounds can be directly or indirectly synthesized from it.

[0003] There are two traditional routes for synthesizing diethyl methylphosphite: the first is to use diethyl methylphosphite dichloride and anhydrous ethanol as raw materials for synthesis, which has harsh reaction conditions and low product yield; the second is to use diethyl chlorophosphite and methylmagnesium chloride for synthesis by Grignard reaction.

[0004] The prior art adopts a kettle-type batch synthesis of diethyl chlorophosphite, which is to drop phosphorus trichloride into triethyl phosphite with a catalyst at a certain temperature. This method has a long reaction time, which makes the cost of diethyl methylphosphite high, and the reaction is incomplete, so that a large amount of phosphorus trichloride remains in the product. The excess phosphorus trichloride will remain in the reaction system and react with the Grignard reagent methylmagnesium chloride in the next step to generate trimethylphosphine, which is very prone to flash explosion and combustion. In addition, trimethylphosphine has a strong unpleasant odor and is easy to damage the environment, which does not meet the requirements of modern industrial production of green and environmental protection. Summary of the invention

[0005] The invention aims to provide an efficient synthesis process of a glufosinate-ammonium intermediate, wherein the surface of a foamed copper particle becomes rougher by etching it with nitric acid, the surface of the foamed copper particle is subjected to chemical nickel plating treatment, a nickel layer with corrosion resistance is generated on the surface, and a nickel hydroxide layer in close contact is grown on the surface by secondary etching treatment with urea, the surface of the nickel hydroxide layer has abundant hydroxyl (-OH) functional groups, an organic skeleton with porosity and adsorption capacity is generated in situ on the surface by the hydroxyl groups, and carbonized on the surface, thereby obtaining a nickel-plated foamed copper particle with high strength and a carbon layer wrapped on the surface, and the hydroxyl groups remaining on the surface are combined with the carboxyl groups of p-hydroxybenzoic acid to generate a metal skeleton with catalytic activity in situ on the surface, thereby improving the catalytic efficiency and service life of the catalyst, improving the productivity of the glufosinate-ammonium intermediate, improving the utilization rate of phosphorus trichloride, and avoiding the generation of byproducts such as phosphorus trichloride residue due to incomplete reaction.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] An efficient synthesis process of a glufosinate-ammonium intermediate is prepared by the following steps:

[0008] Step 1: adding foam copper particles and a nitric acid solution with a concentration of 0.4-0.5 mol / L into a reactor, performing acid etching treatment for 2-3 minutes at 40-45°C and 400-500 r / min, filtering, washing the treated foam copper particles with deionized water until the last washing liquid is neutral, and obtaining roughened foam copper particles; chemically nickel-plating the roughened foam copper particles to obtain nickel-plated foam copper powder with a surface nickel film thickness of 5-10 μm; adding the nickel-plated foam copper powder, urea and deionized water into a reactor, heating to 120-130°C and 400-500 r / min, stirring for 24-26 hours, filtering, washing the filter cake with deionized water until the last washing liquid is neutral, and vacuum drying at 60-80°C for 1-2 hours to obtain roughened nickel-plated foam copper particles.

[0009] Step 2: Add roughened nickel-plated copper foam particles, p-carboxybenzaldehyde and deionized water into the reactor, stir for 40-45 minutes at 20-25°C and 500-700r / min, add 1,3,5-tri(4-aminophenyl)benzene into the reactor, continue stirring for 10-12 minutes, then add dimethylacetamide, N,N-dimethylformamide, and a concentration of 4-5 mo l / L acetic acid solution is added to the reactor, and stirring is continued for 1-2h. Then magnesium chloride hexahydrate is added to the reactor, and stirring is continued for 1-2h. The reaction is filtered, and the filter cake is washed with deionized water and anhydrous ethanol for 2-3 times respectively. The filter cake is transferred to a muffle furnace, heated to 550-600°C, and stirring is continued for 48-50h at 400-500r / min. The filter cake is cooled naturally, and washed with deionized water and anhydrous ethanol for 2-3 times respectively. The filter cake is dried in vacuo at 60-80°C for 1-2h to obtain porous carbon-wrapped nickel-plated copper foam.

[0010] Step 3: Add porous carbon-wrapped nickel-plated copper foam, p-hydroxybenzoic acid and deionized water into a reactor, add a mixed solution of sodium hexadecyl sulfate and 60-70% ethanol by mass as a surfactant, stir at 50-60°C and 400-500r / min for 1-2h, add magnesium sulfate heptahydrate into the reactor, continue stirring and reacting for 3-4h, filter, wash the filter cake with deionized water 2-3 times, and vacuum dry at 60-80°C for 14-16h to obtain a high-efficiency catalytic material.

[0011] Step 4: Add triethyl phosphite and high-efficiency catalytic material into a reactor, stir for 30-40 minutes at 20-25°C and 400-500r / min under nitrogen protection, cool to 0-4°C, add phosphorus trichloride, add iodine element into the reactor, add tetrahydrofuran as a solvent, pass methyl chloride at a rate of 5-6mL / min for 30-40 minutes, cool to -20°C to -30°C, add diethylene glycol dimethyl ether as a solvent, heat to 20-25°C and keep warm for reaction for 1-2h, distill at atmospheric pressure to remove tetrahydrofuran, and perform vacuum distillation to obtain a glufosinate intermediate.

[0012] Furthermore, in step 1, the pore size of the foam copper particles is 0.5-2 mm, and the particle size is 5-20 mm.

[0013] Furthermore, in step 1, the usage ratio of the foam copper particles to the nitric acid is 40-50 g: 200-300 mL.

[0014] Furthermore, in step 1, the usage ratio of the roughened copper foam particles, glyceryl monostearate, nickel sulfate, citric acid and L-cystine is 20-22 g: 1-2 g: 800-900 mL: 2-4 g: 1-2 g.

[0015] Furthermore, the specific steps of chemical nickel plating in step 1 are as follows:

[0016] Roughened copper foam particles, glyceryl monostearate as a surfactant, nickel sulfate, citric acid as a complexing agent and L-cystine as a stabilizer are heated to 80-90° C. and stirred at 400-500 r / min for 40-50 min, filtered, and the filter cake is washed with deionized water until the last washing liquid is neutral to obtain nickel-plated copper foam powder.

[0017] Furthermore, the usage ratio of nickel-plated copper foam powder, urea and deionized water is 10-15 g: 2-3 g: 400-500 mL.

[0018] Furthermore, in step 2, the usage ratio of the roughened nickel-plated copper foam particles, p-carboxybenzaldehyde, deionized water, 1,3,5-tri(4-aminophenyl)benzene, dimethylacetamide, N,N-dimethylformamide, acetic acid and magnesium chloride hexahydrate is 10-12g:12-15g:300-400mL:10-14g:3-4mL:4-5mL:1-2g:15-17g.

[0019] Furthermore, in step three, the usage ratio of porous carbon-wrapped nickel-plated copper foam, p-hydroxybenzoic acid, deionized water, sodium hexadecyl sulfate, ethanol and magnesium sulfate heptahydrate is 8-10g:5-7g:400-500mL:1-2g:80-90mL:5-6g.

[0020] Furthermore, in step 4, the usage ratio of triethyl phosphite, high-efficiency catalytic material, phosphorus trichloride, elemental iodine, tetrahydrofuran and diethylene glycol dimethyl ether is 70-80g: 2-4g: 30-40g: 2-3 grains: 400-500mL: 400-500mL.

[0021] Beneficial effects of the present invention:

[0022] 1. The glufosinate-ammonium intermediate prepared by the present invention has the characteristics of high productivity, high raw material utilization rate and low by-products by adding high-efficiency catalytic materials in the production process; the high-efficiency catalytic materials of the present invention are etched by nitric acid on the foam copper particles to make their surfaces rougher and increase their porosity, and the surface of the foam copper is nickel-plated to generate a nickel layer with corrosion resistance on the surface, and the foam copper particles with rough surfaces can improve the adhesion with the nickel layer, and improve the corrosion resistance of the nickel layer on the foam copper substrate; through secondary urea etching treatment, a nickel hydroxide layer in close contact is grown on the surface, and the surface has rich hydroxyl (-OH) functional groups, and an organic skeleton with porosity and adsorption capacity is in situ generated on the surface by the hydroxyl groups, and carbonized on the surface, so as to obtain a nickel-plated foam copper with high strength and a surface covered by a carbon layer.

[0023] 2. The porous carbon-wrapped nickel-plated copper foam of the present invention etches the copper foam particles with nitric acid to make their surface rougher and increase their porosity, and then nickel-plates the copper foam surface. The nickel-plating treatment can effectively protect the matrix of the copper foam and prevent it from being damaged during the catalytic reaction. The nickel layer has good chemical stability and mechanical strength and can resist the erosion and physical wear of most chemical substances. In the catalytic reaction, the nickel-plated copper foam has stronger corrosion resistance, thereby extending the service life of the copper foam as a catalyst carrier. The nickel-plated copper foam powder is etched in uric acid to grow a layer of tightly contacted nickel hydroxide layer on the surface. The surface has rich hydroxyl (-OH) functional groups, so that an organic skeleton can be uniformly generated on the surface to avoid agglomeration of the organic skeleton. The organic skeleton can further improve the adsorption capacity, thereby improving the efficiency of the high-efficiency catalytic material in catalyzing the synthesis of glufosinate-ammonium intermediates and avoiding incomplete reaction. DETAILED DESCRIPTION

[0024] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] Example 1: An efficient synthesis process of a glufosinate-ammonium intermediate, prepared by the following steps:

[0026] S1: 40g of foam copper particles with a pore size of 0.5-2mm and a particle size of 5-20mm and 200mL of a 0.4mol l / L nitric acid solution is added to the reactor, acid etching is performed for 2 minutes at 40°C and 400r / min, and the treated foam copper particles are washed with deionized water until the last washing liquid is neutral to obtain roughened foam copper particles; 20g of roughened foam copper particles, 1g of monostearate as a surfactant, 800mL of nickel sulfate, 2g of citric acid as a complexing agent and 1g of L-cystine as a stabilizer are heated to 80°C and stirred at 400r / min for 40min, filtered, and the filter cake is washed with deionized water until the last washing liquid is neutral to obtain nickel-plated foam copper powder with a surface nickel film thickness of 5μm; 10g of nickel-plated foam copper powder, 2g of urea and 400mL of deionized water are added to the reactor, heated to 120°C and stirred at 400r / min for 24h, filtered, the filter cake is washed with deionized water until the last washing liquid is neutral, and vacuum dried at 60°C for 1h to obtain roughened nickel-plated foam copper particles.

[0027] The copper foam particles are etched with nitric acid to make their surface rougher and more porous. The copper foam surface is nickel-plated. The nickel plating can effectively protect the copper foam matrix and prevent it from being damaged during the catalytic reaction. The nickel layer has good chemical stability and mechanical strength and can resist the erosion and physical wear of most chemical substances. In the catalytic reaction, the nickel-plated copper foam has stronger corrosion resistance, thereby extending the service life of the copper foam as a catalyst carrier. The nickel-plated copper foam powder is etched in uric acid to grow a tightly contacted nickel hydroxide layer on the surface, and its surface has rich hydroxyl (-OH) functional groups.

[0028] S2: 10g of roughened nickel-plated copper foam particles, 12g of p-carboxylbenzaldehyde and 300mL of deionized water were added to the reactor, stirred at 20°C and 500r / min for 40min, 10g of 1,3,5-tri(4-aminophenyl)benzene was added to the reactor, and stirring was continued for 10min. Then 3mL of dimethylacetamide, 4mL of N,N-dimethylformamide and 1g of 4mol / L acetic acid solution were added to the reactor, and stirring was continued for 1h. Then 15g of magnesium chloride hexahydrate was added to the reactor, and stirring was continued for 1h. The filter cake was washed twice with deionized water and anhydrous ethanol respectively, transferred to a muffle furnace, heated to 550°C, and stirred for 48h at 400r / min. The filter cake was washed twice with deionized water and anhydrous ethanol respectively, and vacuum dried at 60°C for 1h to obtain porous carbon-wrapped nickel-plated copper foam.

[0029] The roughened nickel-plated copper foam particles have abundant hydroxyl (-OH) functional groups on their surface, which are bonded to the carboxyl groups of p-carboxybenzaldehyde to generate an organic skeleton with porosity and adsorption capacity in situ, and carbonize on the surface to obtain a nickel-plated copper foam with high strength and a carbon layer on the surface.

[0030] S3: 8g of porous carbon-wrapped nickel-plated copper foam, 5g of p-hydroxybenzoic acid and 400mL of deionized water were added into a reactor, and a mixed solution of 1g of sodium hexadecyl sulfate as a surfactant and 80mL of 60% ethanol by mass was added, and stirred at 50°C and 400r / min for 1h. 5g of magnesium sulfate heptahydrate was added into the reactor, and the stirring reaction was continued for 3h. The reaction was filtered, and the filter cake was washed twice with deionized water, and vacuum dried at 70°C for 15h to obtain a high-efficiency catalytic material.

[0031] The remaining hydroxyl groups on the surface of nickel-plated copper foam are wrapped by porous carbon and combined with the carboxyl groups of p-hydroxybenzoic acid to generate a catalytically active metal skeleton in situ on the surface.

[0032] S4: Add 70g of triethyl phosphite and 2g of high-efficiency catalytic material into a reactor, stir at 20°C and 400r / min for 30min under nitrogen protection, cool to 0°C, add 35g of phosphorus trichloride, add 2 iodine particles into the reactor, add 450mL of tetrahydrofuran as a solvent, pass chloroform at a rate of 5mL / min for 30min, cool to -20°C, add 400mL of diethylene glycol dimethyl ether as a solvent, heat to 20°C and keep warm for reaction for 1h, distill at atmospheric pressure to remove tetrahydrofuran, and perform vacuum distillation to obtain a glufosinate intermediate.

[0033] Example 2: An efficient synthesis process of a glufosinate-ammonium intermediate, prepared by the following steps:

[0034] S1: 45 g of copper foam particles with a pore size of 0.5-2 mm and a particle size of 5-20 mm and 250 mL of a nitric acid solution with a concentration of 0.45 mol / L were added to a reactor, and acid-etched for 2.5 min at 43° C. and 450 r / min, filtered, and the treated copper foam particles were washed with deionized water until the last washing liquid was neutral to obtain roughened copper foam particles; 21 g of roughened copper foam particles, 1.2 g of glyceryl monostearate as a surfactant, 850 mL of nickel sulfate, 2.4 g of citric acid as a complexing agent, and 1.2 g of L-cystine as a stabilizer were heated to 85° C. and 450 r / min. min, stirred for 45 min, filtered, and washed the filter cake with deionized water until the last washing liquid was neutral to obtain nickel-plated copper foam powder with a surface nickel film thickness of 7 μm; 13 g of nickel-plated copper foam powder, 2.3 g of urea and 450 mL of deionized water were added to a reactor, heated to 125°C and stirred at 450 r / min for 25 h, filtered, washed the filter cake with deionized water until the last washing liquid was neutral, and vacuum dried at 70°C for 1.2 h to obtain roughened nickel-plated copper foam particles.

[0035] S2: 11g of roughened nickel-plated copper foam particles, 13g of p-carboxylbenzaldehyde and 350mL of deionized water were added to the reactor, stirred at 23°C and 600r / min for 43min, 13g of 1,3,5-tri(4-aminophenyl)benzene was added to the reactor, and stirring was continued for 11min. Then 3.5mL of dimethylacetamide, 4.5mL of N,N-dimethylformamide and 1.5g of 4.5mol / L acetic acid solution were added to the reactor, and stirring was continued for 1.2h. Then 16g of magnesium chloride hexahydrate was added to the reactor, and stirring was continued for 1.2h. The filter cake was washed twice with deionized water and anhydrous ethanol respectively, transferred to a muffle furnace, heated to 580°C, and stirred for 49h at 450r / min. The filter cake was washed three times with deionized water and anhydrous ethanol respectively, and vacuum dried at 80°C for 2h to obtain porous carbon-wrapped nickel-plated copper foam.

[0036] S3: 9g of porous carbon-wrapped nickel-plated copper foam, 5.5g of p-hydroxybenzoic acid and 450mL of deionized water were added into a reactor, and a mixed solution of 1.2g of sodium hexadecyl sulfate as a surfactant and 85mL of 65% ethanol by mass was added, and stirred at 55°C and 450r / min for 1.2h. 5.5g of magnesium sulfate heptahydrate was added into the reactor, and the stirring reaction was continued for 3.5h. The reaction was filtered, and the filter cake was washed twice with deionized water, and vacuum dried at 70°C for 15h to obtain a high-efficiency catalytic material.

[0037] S4: Add 75g of triethyl phosphite and 2.4g of high-efficiency catalytic material into a reactor, stir at 23°C and 450r / min for 35min under nitrogen protection, cool to 3°C, add 35g of phosphorus trichloride, add 3 iodine particles into the reactor, add 450mL of tetrahydrofuran as a solvent, pass chloroform at a rate of 5.5mL / min for 35min, cool to -25°C, add 450mL of diethylene glycol dimethyl ether as a solvent, heat to 23°C and keep warm for 1.2h, distill at atmospheric pressure to remove tetrahydrofuran, and perform vacuum distillation to obtain a glufosinate intermediate.

[0038] Example 3: An efficient synthesis process of a glufosinate-ammonium intermediate, prepared by the following steps:

[0039] S1: 50g of foam copper particles with a pore size of 0.5-2mm and a particle size of 5-20mm and 300mL of a concentration of 0.5mo l / L nitric acid solution is added to a reactor, and acid treatment is performed for 3 minutes at 45°C and 500r / min, filtered, and the treated foam copper particles are washed with deionized water until the last washing liquid is neutral to obtain roughened foam copper particles; 22g of roughened foam copper particles, 2g of monostearate as a surfactant, 900mL of nickel sulfate, 4g of citric acid as a complexing agent and 2g of L-cystine as a stabilizer are heated to 90°C and stirred at 500r / min for 50min, filtered, and the filter cake is washed with deionized water until the last washing liquid is neutral to obtain nickel-plated foam copper powder with a surface nickel film thickness of 10μm; 15g of nickel-plated foam copper powder, 3g of urea and 500mL of deionized water are added to a reactor, heated to 130°C and stirred at 500r / min for 26h, filtered, and the filter cake is washed with deionized water until the last washing liquid is neutral, and vacuum dried at 80°C for 2h to obtain roughened nickel-plated foam copper particles.

[0040] S2: 12g of roughened nickel-plated copper foam particles, 15g of p-carboxylbenzaldehyde and 400mL of deionized water were added to the reactor, stirred at 25°C and 700r / min for 45min, 14g of 1,3,5-tri(4-aminophenyl)benzene was added to the reactor, and stirring was continued for 12min. Then 4mL of dimethylacetamide, 5mL of N,N-dimethylformamide and 2g of acetic acid solution with a concentration of 5mol / L were added to the reactor, and stirring was continued for 2h. Then 17g of magnesium chloride hexahydrate was added to the reactor, and stirring was continued for 2h. The filter cake was washed with deionized water and anhydrous ethanol for 3 times respectively, transferred to a muffle furnace, heated to 600°C, and stirred for 50h at 500r / min. The filter cake was washed with deionized water and anhydrous ethanol for 3 times respectively, and dried in vacuo at 80°C for 2h to obtain porous carbon-wrapped nickel-plated copper foam.

[0041] S3: 10g of porous carbon-wrapped nickel-plated copper foam, 7g of p-hydroxybenzoic acid and 500mL of deionized water were added into a reactor, and 2g of sodium hexadecyl sulfate as a surfactant and 90mL of a 70% ethanol mixed solution were added, and stirred at 60°C and 500r / min for 2h. 6g of magnesium sulfate heptahydrate was added into the reactor, and the stirring reaction was continued for 4h. The mixture was filtered, and the filter cake was washed with deionized water for 3 times, and vacuum dried at 80°C for 16h to obtain a high-efficiency catalytic material.

[0042] S4: Add 80g of triethyl phosphite and 4g of high-efficiency catalytic material into a reactor, stir at 25°C and 500r / min for 40min under nitrogen protection, cool to 4°C, add 40g of phosphorus trichloride, add 3 iodine particles into the reactor, add 500mL of tetrahydrofuran as a solvent, pass chloroform at a rate of 6mL / min for 40min, cool to -30°C, add 500mL of diethylene glycol dimethyl ether as a solvent, heat to 25°C and keep warm for 2h, distill at atmospheric pressure to remove tetrahydrofuran, and perform vacuum distillation to obtain a glufosinate intermediate.

[0043] Comparative Example 1: On the basis of Example S3, the roughened copper foam particles in step S1 are replaced with the copper foam particles in step S1, and the other steps remain unchanged to prepare a glufosinate-ammonium intermediate.

[0044] Comparative Example 2: Based on Example S3, the roughened nickel-plated copper foam particles in step S2 are replaced with the nickel-plated copper foam powder in step S1, and the other steps remain unchanged to prepare a glufosinate-ammonium intermediate.

[0045] Comparative Example 3: Based on Example S3, the porous carbon-wrapped nickel-plated copper foam in step S3 is replaced by the roughened nickel-plated copper foam particles in step S1, and the other steps remain unchanged to prepare a glufosinate-ammonium intermediate.

[0046] The performance of the high-efficiency catalytic materials prepared in Examples 1 to 3 and Comparative Examples 1 to 3 in catalyzing the synthesis of glufosinate-ammonium intermediates was tested, and the performance of the catalytic synthesis of glufosinate-ammonium intermediates was tested again after being recycled 100 times after being regenerated by charcoal burning at 400° C. The results are shown in Table 1:

[0047] The calculation method of phosphorus trichloride conversion rate and glufosinate ammonium intermediate selectivity is as follows: phosphorus trichloride conversion rate = (phosphorus trichloride content in raw material - phosphorus trichloride content in product) / phosphorus trichloride content in raw material × 100wt%,

[0048] Selectivity of glufosinate intermediate = (content of glufosinate intermediate in product - content of glufosinate intermediate in raw material) / (content of glufosinate intermediate in raw material - content of glufosinate intermediate in product) × 100 wt %; the results are shown in Table 1:

[0049] Table 1 Catalytic synthesis results of glufosinate-ammonium intermediates

[0050] project Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Conversion rate wt% 60.2 65.6 70.9 42.8 43.3 42.5 Conversion rate after 100 times wt% 59.8 63.5 68.5 38.2 39.1 38.1 Selectivity wt% 97.2 97.4 97.7 85.3 86.7 85.2 Selectivity wt% after 100 times 95.5 95.8 96.1 80.2 81.5 80.3

[0051] As can be seen from Table 1, the glufosinate-ammonium intermediates prepared in Examples 1 to 3 of the present invention have high selectivity and high conversion rate to phosphorus trichloride. After regeneration, the values ​​in Examples 1 to 3 are slightly reduced, with no significant difference, but the decrease in the values ​​in the comparative example is greater than that in the example, indicating that the catalyst prepared by the present invention can efficiently and stably catalyze the synthesis of the glufosinate-ammonium intermediate.

[0052] In Comparative Example 1, the roughened copper foam particles are replaced with the copper foam particles, and the copper foam is acid-etched to remove part of the material on the surface of the copper foam through a chemical reaction, thereby increasing the roughness of its surface. The rough surface helps to enhance the bonding strength between the copper foam and the nickel layer and improve the adhesion of the nickel layer. If the copper foam is not acid-etched, the overall performance of the copper foam as a catalyst matrix is ​​reduced, which in turn leads to a reduction in the catalytic effect, affecting the catalytic effect, and reducing the purity and quality of the product. After 100 cycles of use, the adhesion of the nickel layer is significantly reduced, resulting in a performance test performance decline greater than that of the embodiment.

[0053] In Comparative Example 2, the roughened nickel-plated copper foam particles replace the nickel-plated copper foam powder. After secondary etching with urea, a tightly contacted nickel hydroxide layer grows on the surface. The surface of the nickel hydroxide layer has abundant hydroxyl (-OH) functional groups, which can be tightly combined with the organic skeleton to avoid uneven dispersion and agglomeration of the organic skeleton. Without secondary etching, the organic skeleton loaded on the surface will be unevenly distributed, and carbonization will form an uneven carbon layer on the surface, which will affect the surface structure and porosity of the catalyst, affect the catalytic efficiency, and reduce the purity and quality of the product. After 100 cycles of use, the uneven carbon layer formed on the surface will fall off, thereby changing the porosity of the catalyst surface, resulting in a performance test performance decline greater than that of the embodiment.

[0054] In Comparative Example 3, the porous carbon-wrapped nickel-plated copper foam is replaced with roughened nickel-plated copper foam particles. The hydroxyl groups on the surface combine with p-carboxylbenzaldehyde to form a uniform organic skeleton on the surface, further increasing the specific surface area of ​​the catalyst. A high specific surface area means more active sites. The carbon layer formed after carbonization has certain mechanical strength and chemical stability, which can protect the roughened nickel-plated copper foam particle matrix from corrosion or wear, thereby extending the service life of the catalyst.

[0055] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0056] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An efficient synthesis process of a glufosinate-ammonium intermediate, characterized in that: Prepared by the following steps: Step 1: Add porous carbon-wrapped nickel-plated copper foam, p-hydroxybenzoic acid and deionized water into a reactor, add a mixed solution of sodium hexadecyl sulfate and 60-70% ethanol by mass as a surfactant, stir at 50-60° C. and 400-500 r / min for 1-2 hours, add magnesium sulfate heptahydrate into the reactor, continue stirring and reacting for 3-4 hours, filter, wash the filter cake with deionized water for 2-3 times, and vacuum dry at 60-80° C. for 14-16 hours to obtain a high-efficiency catalytic material; Step 2: Add triethyl phosphite and high-efficiency catalytic material into a reactor, stir at 20-25°C and 400-500r / min for 30-40min under nitrogen protection conditions, cool to 0-4°C, add phosphorus trichloride, add iodine element into the reactor, add tetrahydrofuran, pass methyl chloride at a rate of 5-6mL / min for 30-40min, cool to -20°C to -30°C, add diethylene glycol dimethyl ether, heat to 20-25°C and keep warm for reaction for 1-2h, distill at atmospheric pressure to remove tetrahydrofuran, and perform vacuum distillation to obtain a glufosinate intermediate.

2. The efficient synthesis process of a glufosinate-ammonium intermediate according to claim 1, characterized in that: The usage ratio of the porous carbon-wrapped nickel-plated copper foam, p-hydroxybenzoic acid, deionized water, sodium hexadecyl sulfate, ethanol and magnesium sulfate heptahydrate in step 1 is 8-10g:5-7g:400-500mL:1-2g:80-90mL:5-6g.

3. The efficient synthesis process of a glufosinate-ammonium intermediate according to claim 1, characterized in that: The usage ratio of triethyl phosphite, high-efficiency catalytic material, phosphorus trichloride, elemental iodine, tetrahydrofuran and diethylene glycol dimethyl ether in step 2 is 70-80g: 2-4g: 30-40g: 2-3 grains: 400-500mL: 400-500mL.

4. The efficient synthesis process of a glufosinate-ammonium intermediate according to claim 1, characterized in that: The porous carbon-wrapped nickel-plated copper foam described in step 1 is prepared by the following steps: Roughened nickel-plated copper foam particles, p-carboxylbenzaldehyde and deionized water are added to a reactor, stirred at 20-25°C and 500-700r / min for 40-45min, 1,3,5-tri(4-aminophenyl)benzene is added to the reactor, stirred for 10-12min, dimethylacetamide, N,N-dimethylformamide and acetic acid solution with a concentration of 4-5mol / L are added to the reactor, stirred for 1-2h, magnesium chloride hexahydrate is added to the reactor, stirred for 1-2h, filtered, the filter cake is washed with deionized water and anhydrous ethanol for 2-3 times, transferred to a muffle furnace, heated to 550-600°C, stirred at 400-500r / min for 48-50h, cooled naturally, the filter cake is washed with deionized water and anhydrous ethanol for 2-3 times, vacuum dried to obtain porous carbon-wrapped nickel-plated copper foam.

5. The efficient synthesis process of a glufosinate-ammonium intermediate according to claim 4, characterized in that: The roughened nickel-plated copper foam particles, p-carboxybenzaldehyde, deionized water, 1,3,5-tri(4-aminophenyl)benzene, dimethylacetamide, N,N-dimethylformamide, acetic acid and magnesium chloride hexahydrate are used in a ratio of 10-12 g: 12-15 g: 300-400 mL: 10-14 g: 3-4 mL: 4-5 mL: 1-2 g: 15-17 g.

6. The efficient synthesis process of a glufosinate-ammonium intermediate according to claim 4, characterized in that: The roughened nickel-plated copper foam particles are prepared by the following steps: The roughened copper foam particles are subjected to chemical nickel plating to obtain nickel-plated copper foam powder having a surface nickel film thickness of 5-10 μm; the nickel-plated copper foam powder, urea and deionized water are added to a reaction kettle, heated to 120-130° C. and stirred at 400-500 r / min for 24-26 hours, filtered, the filter cake is washed with deionized water until the last washing liquid is neutral, and vacuum dried to obtain roughened nickel-plated copper foam particles; The usage ratio of the nickel-plated copper foam powder, urea and deionized water is 10-15g:2-3g:400-500mL.

7. The efficient synthesis process of a glufosinate-ammonium intermediate according to claim 6, characterized in that: The specific steps of the chemical nickel plating are as follows: Roughened copper foam particles, glyceryl monostearate, nickel sulfate, citric acid and L-cystine are heated to 80-90°C and stirred at 400-500 r / min for 40-50 min, filtered, and the filter cake is washed with deionized water until the last washing liquid is neutral to obtain nickel-plated copper foam powder with a surface nickel film thickness of 5-10 μm.

8. The efficient synthesis process of a glufosinate-ammonium intermediate according to claim 7, characterized in that: The usage ratio of the roughened copper foam particles, glyceryl monostearate, nickel sulfate, citric acid and L-cystine is 20-22 g: 1-2 g: 800-900 mL: 2-4 g: 1-2 g.

9. The efficient synthesis process of a glufosinate-ammonium intermediate according to claim 8, characterized in that: The roughened copper foam particles are prepared by the following steps: Adding the foam copper particles and a nitric acid solution with a concentration of 0.4-0.5 mol / L into a reaction kettle, performing acid etching treatment at 40-45° C. and 400-500 r / min for 2-3 min, filtering, and washing the treated foam copper particles with deionized water until the last washing liquid is neutral, thereby obtaining roughened foam copper particles; The usage ratio of the foam copper particles and nitric acid is 40-50g:200-300mL; the pore size of the foam copper particles is 0.5-2mm, and the particle size is 5-20mm.

10. A glufosinate-ammonium intermediate, characterized in that: The invention is prepared by a highly efficient synthesis process of a glufosinate-ammonium intermediate as described in any one of claims 1 to 9.