阅读说明：本技术 一种苯醚甲环唑粗品精制方法 (Refining method of difenoconazole crude product ) 是由 冯魏 贾利华 陈华 陈石秀 徐鹏鹏 邢燕 于 2021-09-13 设计创作，主要内容包括：本发明公开了一种苯醚甲环唑粗品精制方法,采用萃取结晶的方法精制苯醚甲环唑,先萃取后结晶,整个精制过程中不引入强酸、不引入碱液,精制过程无废盐产生；无需精馏,无精馏残渣及高COD废水产生。萃取母液和结晶母液经过脱净萃取溶剂后得到低含量的苯醚甲环唑的颜色较浅,可以直接配制成10%苯醚甲环唑水乳剂,水乳剂质量高,实现废物再利用,苯醚甲环唑粗品利用率达到98%以上。(The invention discloses a refining method of a difenoconazole crude product, which adopts an extraction crystallization method to refine difenoconazole, wherein the difenoconazole is extracted firstly and then crystallized, strong acid and alkali liquor are not introduced in the whole refining process, and no waste salt is generated in the refining process; no rectification, no rectification residue and no high COD waste water. The extraction mother liquor and the crystallization mother liquor are subjected to extraction solvent removal to obtain low-content difenoconazole with lighter color, 10% difenoconazole water emulsion can be directly prepared, the quality of the water emulsion is high, waste recycling is realized, and the utilization rate of a difenoconazole crude product reaches more than 98%.)

1. A refining method of a difenoconazole crude product is characterized by comprising the following steps:

comprises the steps of extraction and crystallization;

the extraction steps are as follows: extracting the crude product of difenoconazole for at least 1 time by using an extraction solvent to extract the difenoconazole to be crystallized;

the crystallization step is as follows: and mixing and fully dissolving difenoconazole to be crystallized and a crystallization solvent, and cooling and crystallizing to obtain the difenoconazole technical product.

2. The refining method of crude difenoconazole according to claim 1, which is characterized in that: the extraction steps are specifically as follows: adding a difenoconazole crude product and an extraction solvent into a reaction vessel, heating to reflux and extracting for 0.5-1h, cooling to 70 ℃, carrying out phase splitting, and separating out the extraction solvent; and continuously adding an extraction solvent, carrying out second extraction, carrying out third extraction after the second extraction is finished, separating to obtain difenoconazole to be crystallized, and removing the extraction solvent from the extraction mother liquor to obtain the low-content difenoconazole.

3. The refining method of the difenoconazole crude product as recited in claim 2, characterized in that: in the three extractions, the mass ratio of the extraction solvent added each time to the crude difenoconazole is 4-6: 1.

4. The refining method of the difenoconazole crude product as recited in claim 2, characterized in that: the mass content of the difenoconazole in the crude difenoconazole is 70-83%; the mass content of the difenoconazole to be crystallized is 96-97 percent; the mass content of the low content difenoconazole is 50-66.3%.

5. The refining method of crude difenoconazole according to claim 4, which is characterized in that: the low-content difenoconazole is used for preparing difenoconazole water emulsion with the mass content of 10%.

6. The refining method of crude difenoconazole according to claim 1, which is characterized in that: the crystallization step specifically comprises: adding difenoconazole to be crystallized and a crystallization solvent into a crystallization container, mixing, heating to 60-70 ℃ for dissolution, cooling to-10-0 ℃ for crystallization for 6-8h after complete dissolution, and performing suction filtration and drying to obtain a difenoconazole raw drug; and (3) removing the crystallization solvent from the crystallization mother liquor to obtain low-content difenoconazole, wherein the low-content difenoconazole is used for preparing 10% of difenoconazole water emulsion.

7. The refining method of crude difenoconazole according to claim 6, which is characterized in that: the mass ratio of the crystallization solvent to the difenoconazole to be crystallized is 1-1.2: 1.

8. The refining method of crude difenoconazole according to claim 6, which is characterized in that: the mass content of the difenoconazole technical material is 97-98%.

9. The refining method of crude difenoconazole according to any one of claims 1-8, characterized in that: the extraction solvent is n-heptane, mixed heptane, methylcyclohexane or cyclohexane.

10. The refining method of crude difenoconazole according to any one of claims 1-8, characterized in that: the crystallization solvent is 85-90% by mass of methanol, 95% by mass of ethanol or 98-99% by mass of isopropanol.

Technical Field

The invention relates to a refining method of a difenoconazole crude product, belonging to an organic chemical post-treatment technology.

Background

At present, the content of crude difenoconazole in industrial production is mostly 70-83%, and the common refining method comprises salifying by concentrated nitric acid or concentrated hydrochloric acid, obtaining high-content difenoconazole by alkaline hydrolysis extraction, and then recrystallizing to obtain the difenoconazole technical product. The method can generate a large amount of sodium nitrate or sodium chloride waste salt, thereby greatly increasing the environmental protection treatment cost; and the color of the mother liquor after alkaline hydrolysis extraction is darker, the mother liquor cannot be prepared into aqueous emulsion, the mother liquor cannot be utilized, and only a third party can be entrusted to carry out incineration and other treatment, so that not only is the resource wasted, but also the environmental protection is not facilitated.

For example, chinese patent CN110204534A discloses a refining method of difenoconazole, which discloses dissolving crude difenoconazole with toluene, then promoting hydrochloride salt formation with hydrogen chloride, adding alkaline water for alkaline hydrolysis after salt formation, removing toluene, and crystallizing to obtain difenoconazole technical product. Although the process is optimized, the steps of salt formation, alkaline hydrolysis and crystallization are essentially carried out, a large amount of waste salt is still generated, and the difenoconazole contained in the alkaline water cannot be recycled, so that certain waste is caused.

Therefore, a technical solution is needed to solve the above technical problems.

Disclosure of Invention

The invention aims to provide a novel refining method without salification aiming at the defects of the existing difenoconazole refining process, and the method does not need to introduce strong acid or alkaline hydrolysis, does not generate a large amount of waste salt, and is environment-friendly.

The technical scheme adopted by the invention for solving the problems is as follows:

a refining method of a difenoconazole crude product comprises the steps of extraction and crystallization; the extraction steps are as follows: extracting the crude product of difenoconazole for at least 1 time by using an extraction solvent to extract the difenoconazole to be crystallized; the crystallization step is as follows: and mixing and fully dissolving difenoconazole to be crystallized and a crystallization solvent, and cooling and crystallizing to obtain the difenoconazole technical product.

Further, the extraction step specifically comprises: adding a difenoconazole crude product and an extraction solvent into a reaction vessel, heating to reflux and extracting for 0.5-1h, cooling to 70 ℃, carrying out phase splitting, and separating out the extraction solvent; and continuously adding an extraction solvent, carrying out second extraction, carrying out third extraction after the second extraction is finished, separating to obtain difenoconazole to be crystallized, and removing the extraction solvent from the extraction mother liquor to obtain the low-content difenoconazole. In the three extractions, the mass ratio of the extraction solvent added each time to the crude difenoconazole is 4-6: 1. The mass content of the difenoconazole in the crude difenoconazole is 70-83%; the mass content of the difenoconazole to be crystallized is 96-97 percent; the mass content of the low content difenoconazole is 50-66.3%.

Further, the crystallization step specifically comprises: adding difenoconazole to be crystallized and a crystallization solvent into a crystallization container, mixing, heating to 60-70 ℃ for dissolution, cooling to-10-0 ℃ for crystallization for 6-8h after complete dissolution, and performing suction filtration and drying to obtain the difenoconazole technical product. The mass ratio of the crystallization solvent to the difenoconazole to be crystallized is 1-1.2: 1. The mass content of the difenoconazole technical material is 97-98%.

Further, the extraction solvent is n-heptane, mixed heptane, methylcyclohexane or cyclohexane.

Further, the crystallization solvent is 85-90% by mass of methanol, 95% by mass of ethanol or 98-99% by mass of isopropanol.

Further, the extraction mother liquor and the crystallization mother liquor are subjected to purification and crystallization solvent removal to obtain low-content difenoconazole which is used for preparing the difenoconazole water emulsion with the mass content of 10%.

Compared with the existing refining process, the invention has the beneficial effects that:

1) the difenoconazole is refined by adopting an extraction crystallization method, the difenoconazole is extracted and then crystallized, strong acid and alkali liquor are not introduced in the whole refining process, and no waste salt is generated in the refining process; no rectification, no rectification residue and no high COD waste water.

2) The extraction process is adopted to replace a salt forming process, strong acid is not needed, the extraction mother liquor and the crystallization mother liquor are subjected to extraction solvent removal to obtain low-content difenoconazole with lighter color, 10% difenoconazole water emulsion can be directly prepared, the quality of the water emulsion is high, no waste water is generated, waste recycling is realized, and the utilization rate of the difenoconazole crude product reaches more than 98%.

3) The invention adopts an extraction crystallization refining process, which is simple to operate and easy to control, greatly shortens the refining period, has high purification yield and low production cost, and the whole process is green and environment-friendly.

Detailed Description

In order to make the objects, technical solutions and advantages of the technical solutions of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the specific embodiments of the present invention.

It should be noted that the described embodiments of the invention are only preferred ways of implementing the invention, and that all obvious modifications, which are within the scope of the invention, are all included in the present general inventive concept.

Example 1

100g of difenoconazole crude product with the mass content of 70 percent and 400g of cyclohexane are added into a reaction kettle, heating reflux extraction is carried out for 0.5-1h, the temperature is reduced to 70 ℃ for phase splitting, 400g of cyclohexane is continuously added for secondary extraction after the cyclohexane is separated out, 400g of cyclohexane is continuously added for third extraction after the secondary extraction is finished, the cyclohexane is removed completely to separate out 44g of difenoconazole to be crystallized with the content of 96 percent, 44g of methanol with the mass concentration of 85-90 percent is added, the temperature is increased to 60-70 ℃ for dissolution, the temperature is reduced to-10-0 ℃ for crystallization for 6-8h after the dissolution is completed, suction filtration and drying are carried out to obtain 40g of 97 percent difenoconazole raw drug, and 3.9g of 53.8 percent difenoconazole is obtained by removing solvent from crystallization mother liquor. 56g of low-content difenoconazole with the concentration of 50.4 percent obtained by desolventizing the extraction mother liquor is combined with 3.9g of difenoconazole obtained by desolventizing the crystallization mother liquor, and a solvent, an emulsifier, water, an antifreezing agent and the like are added to prepare the 10 percent difenoconazole water emulsion.

100g of 70% difenoconazole crude product is refined to obtain 40g of 97% difenoconazole technical product, 53.8% of difenoconazole is desolventized in crystallization mother liquor, 3.9g of 50.4% of low-content difenoconazole is 56g, so that the utilization rate of the refined difenoconazole reaches 98.70%, the utilization rate is high, and no waste salt, waste residue and high-concentration COD wastewater is generated in the whole refining process.

Example 2

100g of crude difenoconazole with the mass content of 80 percent and 500g of n-heptane are put into a reaction kettle, the heating reflux extraction is carried out for 0.5 to 1 hour, the temperature is reduced to 70 ℃ for phase splitting, 500g of n-heptane is continuously added for the second extraction after the n-heptane is separated out, 500g of n-heptane is continuously added for the third extraction after the second extraction is finished, the clean n-heptane is removed for separation to obtain 53.5g of difenoconazole to be crystallized with the content of 97 percent, 64.2g of ethanol with the mass concentration of 95 percent is added, the temperature is increased to 60 to 70 ℃ for dissolution, the temperature is reduced to minus 10 to 0 ℃ for crystallization for 6 to 8 hours after the dissolution is completed, the suction filtration and the drying are carried out to obtain 48.7g of 98 percent difenoconazole raw drug, and the clean solvent of crystallization mother liquor is removed to obtain 4.7g of 68.1 percent difenoconazole. And desolventizing the extraction mother liquor to obtain 46.5g of low-content difenoconazole with the concentration of 60.4%, and adding a solvent, an emulsifier, water, an antifreezing agent and the like into the difenoconazole obtained by desolventizing the extraction mother liquor and the crystallization mother liquor to prepare the 10% difenoconazole water emulsion. The utilization rate of the difenoconazole reaches 98.75 percent.

Example 3

100g of 83 mass percent difenoconazole crude product and 600g of methylcyclohexane are put into a reaction kettle, heating and reflux extraction are carried out for 0.5-1h, the temperature is reduced to 70 ℃ for phase splitting, 600g of methylcyclohexane is continuously added for secondary extraction after the methylcyclohexane is separated out, 600g of methylcyclohexane is continuously added for third extraction after the secondary extraction is finished, the decating methylcyclohexane is separated to obtain 56.0g of 96 mass percent difenoconazole to be crystallized, 61.6g of isopropanol with the mass concentration of 98-99 percent is added, the temperature is increased to 60-70 ℃ for dissolution, the temperature is reduced to-10-0 ℃ for crystallization for 6-8h after the dissolution is complete, suction filtration and drying are carried out to obtain 51.0g of 97.5 percent difenoconazole crude drug, and the solvent is removed from crystallization mother liquor to obtain 4.9g of 63.3 percent difenoconazole. The extraction mother liquor is desolventized to obtain 44g of low-content difenoconazole with 66.3 percent, the extraction mother liquor and the crystallization mother liquor are combined to obtain the low-content difenoconazole after desolventization, and a solvent, an emulsifier, water, an antifreezing agent and the like are added into the mixture to prepare the difenoconazole water emulsion with 10 percent. The utilization rate of the difenoconazole reaches 98.80 percent.