CN115057818A - Process for refining crude aminopyrine - Google Patents
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- CN115057818A CN115057818A CN202210921067.3A CN202210921067A CN115057818A CN 115057818 A CN115057818 A CN 115057818A CN 202210921067 A CN202210921067 A CN 202210921067A CN 115057818 A CN115057818 A CN 115057818A
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- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D231/00—Heterocyclic compounds containing 1,2-diazole or hydrogenated 1,2-diazole rings
- C07D231/02—Heterocyclic compounds containing 1,2-diazole or hydrogenated 1,2-diazole rings not condensed with other rings
- C07D231/10—Heterocyclic compounds containing 1,2-diazole or hydrogenated 1,2-diazole rings not condensed with other rings having two or three double bonds between ring members or between ring members and non-ring members
- C07D231/14—Heterocyclic compounds containing 1,2-diazole or hydrogenated 1,2-diazole rings not condensed with other rings having two or three double bonds between ring members or between ring members and non-ring members with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
- C07D231/44—Oxygen and nitrogen or sulfur and nitrogen atoms
- C07D231/46—Oxygen atom in position 3 or 5 and nitrogen atom in position 4
- C07D231/48—Oxygen atom in position 3 or 5 and nitrogen atom in position 4 with hydrocarbon radicals attached to said nitrogen atom
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Abstract
A process for refining a crude aminopyrine product, belonging to the technical field of chemical synthesis pharmacy. The method comprises the following steps: 1) first, subcritical CO is utilized in a subcritical reactor 2 Washing the crude aminopyrine product with subcritical CO 2 Washing the residual extractant in the crude product; 2) after subcritical washing, dissolving aminopyrine in hot water at 99-111 ℃ to obtain an aminopyrine water solution, sending the aminopyrine water solution into a centrifugal machine under the condition of heat preservation for high-speed centrifugation, collecting supernatant, and concentrating, cooling, crystallizing and carrying out solid-liquid separation on the supernatant to obtain a refined crude material; 3) mixing the refined crude material, ethanol and active carbon, heating for refluxing, filtering with membrane to obtain filtrate, cooling, crystallizing, and performing solid-liquid separation to obtain refined product. The method for processing the crude aminopyrine can solve the problem that the crude aminopyrine material is difficult to digest due to the relatively large yield of analgin.
Description
Technical Field
A process for refining a crude aminopyrine product, belonging to the technical field of chemical synthesis pharmacy.
Background
The aminopyrine is a pyrazolone antipyretic, analgesic and anti-inflammatory drug, can inhibit synthesis and release of prostaglandin in local tissues of inflammation, stabilize lysosome membranes, influence phagocytosis of phagocytes, and has anti-inflammatory effect. It also can inhibit synthesis and release of prostaglandin E1 in anterior neurons of hypothalamus, and restore normal response of thermoregulatory central sensory neurons to achieve antipyretic effect.
In the production process of aminopyrine, the crude aminopyrine products are derived from two types: one is obtained by concentrating, cooling, crystallizing and centrifuging the centrifugal mother liquor of the aminopyrine finished product; the other type is obtained by hydrolyzing, methylating and extracting the mother liquor of analgin, which is called as crude aminopyrine. Under the normal balanced production ratio of analgin and aminopyrine, the crude aminopyrine product produced by analgin can be digested by aminopyrine production. However, when the analgin yield is higher than the equilibrium value, the accumulation of the crude aminopyrine is caused, and the ethanol content in the residual liquid of a normal aminopyrine ethanol recovery system is increased sharply if the crude aminopyrine is excessively digested by a production line of the aminopyrine due to the fact that the material contains a trace amount of the extracting agent, so that the cost of the aminopyrine is increased. In addition, forced digestion of the crude aminopyrine also leads to general degradation of the quality of various materials in a recycling system of the mother liquor of the aminopyrine.
The refining method of the crude aminopyrine usually adopts a crystallization form. For example, the production method of aminopyrine disclosed in Chinese patent CN111991693B describes that: and decoloring, crystallizing and drying the aminopyrine crude product obtained in the second hydrogenation reduction reaction step to obtain a finished aminopyrine product. The method is not detailed enough and is not suitable for processing the crude aminopyrine product obtained from the mother liquor of analgin.
The refining method of the aminopyrine crude product disclosed in the Chinese patent CN111713461A is that the aminopyrine crude product, water and active carbon are heated and refluxed according to a proportion, and then the refined crude product is obtained after filtration, cooling, crystallization and centrifugation; heating and refluxing the refined crude material, ethanol and active carbon according to a proportion, and filtering, cooling, crystallizing and centrifuging to obtain a refined material; the crude product processing method can process the crude aminopyrine product materials more quickly; but the final crystallization rate is low.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: overcomes the defects of the prior art and provides a process for refining a crude product of aminopyrine.
The technical scheme adopted by the invention for solving the technical problems is as follows: the process for refining the crude aminopyrine is characterized by comprising the following steps of:
1) first using subcritical CO in a subcritical reactor 2 Washing the crude aminopyrine product with subcritical CO 2 Washing the residual extractant in the crude product;
2) after subcritical washing, dissolving aminopyrine in hot water at 99-111 ℃ to obtain an aminopyrine water solution, sending the aminopyrine water solution into a centrifugal machine under the condition of heat preservation for high-speed centrifugation, collecting supernatant, and concentrating, cooling, crystallizing and carrying out solid-liquid separation on the supernatant to obtain a refined crude material;
3) mixing the refined crude material, ethanol and active carbon, heating for refluxing, filtering with membrane to obtain filtrate, cooling, crystallizing, and performing solid-liquid separation to obtain refined product.
Before refining the crude aminopyrine product by using ethanol, subcritical CO is firstly used 2 Washing to remove residual extractant and partial impurities, dissolving in water, centrifuging, crystallizing to remove impurities, and refining with ethanol. The method gets rid of the problem that the quality influence on an aminopyrine ethanol recovery system possibly caused by a refining process is avoided by only refining the aminopyrine with ethanol in the prior art, so that the problem that the crude aminopyrine material is difficult to digest due to the relatively large yield of analgin is thoroughly solved under the condition of ensuring the crystallization rate and the product purity.
The preferable process for refining the crude aminopyrine comprises the subcritical CO in the step 1) 2 The reaction conditions for washing were: the temperature is less than 314K, and the pressure is less than 7.39 multiplied by 11 6 Pa. Preferred subcritical CO 2 The washing reaction conditions can completely remove the residual extractant.
Preferably, in the step 2), the centrifuge is a continuous high-speed tubular centrifuge, and the rotation speed of the centrifuge is 25111 r/min-31111 r/min. The preferable centrifugal rotating speed can better separate impurities and aminopyrine, and the impurities can be removed more efficiently.
In a preferable process for refining the crude aminopyrine, the use amount of the hot water in the step 2) is 1.9-1.1 times of the mass of the crude aminopyrine. The preferred centrifugation conditions allow for less hot water to wash out impurities.
Preferably, in the step 3), the filtering membrane used for membrane filtration is a ceramic membrane, and the pore diameter of the ceramic membrane is 1.15 to 1.1 microns. The ethanol solution is continuously filtered by using a proper ceramic membrane, and the activated carbon and impurities are efficiently filtered and then recrystallized, so that the product quality is ensured.
The preferable process for refining the crude aminopyrine comprises the step 3) that the mass ratio of the refined crude material to the ethanol to the activated carbon is 1: 1.7-1.9: 1.11 to 1.12. Less ethanol and active carbon can be used for realizing refining and decoloring after the previous impurity treatment, and impurities are removed.
Preferably, in the step 2), the heat preservation condition is to keep the aminopyrine water solution at 91-99 ℃. And (3) centrifuging under a heat preservation condition to prevent the aminopyrine from cooling and crystallizing, and further prevent the crystallized aminopyrine from being centrifugally precipitated to cause material loss.
Preferably, the crystallization temperature in the step 2) is 65-71 ℃; and cooling to below 11 ℃ for solid-liquid separation. The crystallization temperature and the solid-liquid separation temperature are preferably selected, so that the crystallization yield can be better ensured.
Preferably, in the step 3), the heating reflux is carried out by heating to 79-92 ℃, and the reflux decoloring time is 2-3 hours.
Preferably, in the process for refining the crude aminopyrine, the crystallization temperature in the step 3) is 51-61 ℃; and cooling to below 11 ℃ for solid-liquid separation.
The crystallization yield can be better ensured under the preferable ethanol temperature-rising reflux and crystallization process.
The method for processing the crude aminopyrine can solve the problem that the crude aminopyrine material is difficult to digest due to the relatively large yield of analgin. Meanwhile, the method does not affect an aminopyrine ethanol recovery system, and can save ethanol compared with the prior production mode.
Compared with the prior art, the process for refining the crude aminopyrine has the beneficial effects that:
1. the method obtains the refined material through three steps of refining, can be directly applied to material matching in the aminopyrine production process, and can reduce the consumption of active carbon and ethanol in the primary refining process.
2. The process increases subcritical CO 2 Washing, and centrifugally refining the crude aminopyrine material by using hot water, so that the problem that the crude aminopyrine material is difficult to digest due to relatively large yield of analgin is solved.
3. The method is a method for independently processing the aminopyrine crude material, and the condition that the aminopyrine crude material is matched with other materials in the prior art is not needed, so that the quality of the refined aminopyrine material is improved, and the production of the aminopyrine is facilitated.
Detailed Description
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an", and "the" are intended to include the plural forms as well, and furthermore, the terms "comprises" and "having", and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict.
The invention is further illustrated by the following specific examples, of which example 1 is the best mode of practice.
Example 1
Utilization of subcritical CO in subcritical reactor 2 Washing 1000kg of crude aminopyrine under the following reaction conditions: temperature 295K, pressure 5.21X 11 6 Pa, in subcritical CO 2 Washing the residual extractant in the crude product;
after subcritical washing, dissolving aminopyrine in hot water at 99-111 ℃ to obtain an aminopyrine water solution, wherein the using amount of the hot water is 1 time of the mass of the crude aminopyrine product; keeping the water temperature at 95 ℃, sending the aminopyrine water solution into a continuous high-speed tubular centrifuge for high-speed centrifugation at the rotating speed of 31111r/min, collecting supernatant, concentrating, cooling, crystallizing at 65 ℃, cooling to 9 ℃, and carrying out solid-liquid separation to obtain a refined crude product;
putting the obtained refined crude material into a refining tank, adding 751kg of ethanol and 15kg of activated carbon, starting steam in an interlayer of the refining tank, heating to 79 ℃, keeping the temperature at 95 ℃, and decoloring for 2.5 hours; after the decolorization is finished, opening nitrogen in a refining tank, filtering the hot activated carbon by using a ceramic membrane with the aperture of 1.19 mu m, pressing the filtrate into a crystallizing tank, cooling to 55 ℃ for crystallization, cooling to 9 ℃ for centrifugation to obtain a product; the crystallization rate was 72.4%, and the purity of the obtained purified aminopyrine was 99.7%.
Example 2
Utilization of subcritical CO in subcritical reactor 2 Washing 1000kg of crude aminopyrine under the following reaction conditions: temperature 295K, pressure 5.39X 11 6 Pa, in subcritical CO 2 Washing the residual extractant in the crude product;
after subcritical washing, dissolving aminopyrine in hot water at 99-111 ℃ to obtain an aminopyrine water solution, wherein the using amount of the hot water is 1.9 times of the mass of the crude aminopyrine product; keeping the water temperature at 93 ℃, sending the aminopyrine water solution into a continuous high-speed tubular centrifuge for high-speed centrifugation at the rotating speed of 29111r/min, collecting supernatant, concentrating, cooling, crystallizing at 66 ℃, and cooling to 6 ℃ for solid-liquid separation to obtain a refined crude product;
putting the refined crude material into a refining tank, adding 721kg of ethanol and 12kg of activated carbon, heating the steam in the interlayer of the refining tank to 79 ℃, keeping the temperature at 91 ℃, and decoloring for 2.3 hours; after the decolorization is finished, opening nitrogen in a refining tank, filtering the hot activated carbon by using a ceramic membrane with the aperture of 1.17 mu m, pressing the filtrate into a crystallizing tank, cooling to 57 ℃ for crystallization, cooling to 6 ℃ for centrifugation to obtain a product; the crystallization rate was 71.7%, and the purity of the obtained purified aminopyrine was 99.9%.
Example 3
Utilization of subcritical CO in subcritical reactor 2 Washing 1000kg of crude aminopyrine under the following reaction conditions: temperature 311K, pressure 6.5X 11 6 Pa, in subcritical CO 2 Washing the residual extractant in the crude product;
after subcritical washing, dissolving aminopyrine in hot water at 99-111 ℃ to obtain an aminopyrine water solution, wherein the using amount of the hot water is 1.1 times of the mass of the crude aminopyrine product; keeping the water temperature at 96 ℃, sending the aminopyrine water solution into a continuous high-speed tubular centrifuge for high-speed centrifugation at the rotating speed of 27111r/min, collecting supernatant, concentrating, cooling, crystallizing at 69 ℃, and cooling to 9 ℃ for solid-liquid separation to obtain a refined crude product;
putting the obtained refined crude material into a refining tank, adding 791kg of ethanol and 17kg of active carbon, starting steam in an interlayer of the refining tank, heating to 79 ℃, keeping the temperature at 92 ℃, and decoloring for 2.9 hours; after the decolorization is finished, opening nitrogen in a refining tank, filtering the hot activated carbon by using a ceramic membrane with the aperture of 1.19 mu m, pressing the filtrate into a crystallizing tank, cooling to 52 ℃ for crystallization, cooling to 5 ℃ for centrifugation to obtain a product; the crystallization rate was 72.1%, and the purity of the obtained purified aminopyrine was 97.9%.
Example 4
Utilization of subcritical CO in subcritical reactor 2 Washing 1000kg of crude aminopyrine under the following reaction conditions: temperature 311K, pressure 7.11X 11 6 Pa, in subcritical CO 2 Washing the residual extractant in the crude product;
after subcritical washing, dissolving aminopyrine in hot water at 99-111 ℃ to obtain an aminopyrine water solution, wherein the using amount of the hot water is 1.9 times of the mass of the crude aminopyrine product; keeping the water temperature at 99 ℃, sending the aminopyrine water solution into a continuous high-speed tubular centrifuge for high-speed centrifugation at the rotating speed of 25111r/min, collecting supernatant, concentrating, cooling, crystallizing at 71 ℃, cooling to 11 ℃, and carrying out solid-liquid separation to obtain a refined crude product;
putting the obtained refined crude product into a refining tank, adding 711kg of ethanol and 11kg of activated carbon, starting steam in an interlayer of the refining tank, heating to 79 ℃, keeping the temperature at 79 ℃, and decoloring for 3 hours; after the decolorization is finished, opening nitrogen in a refining tank, filtering the hot activated carbon by using a ceramic membrane with the aperture of 1.15 mu m, pressing the filtrate into a crystallizing tank, cooling to 51 ℃ for crystallization, cooling to 4 ℃ for centrifugation to obtain a product; the crystallization rate was 69.3%, and the purity of the obtained purified aminopyrine was 99.4%.
Example 5
Utilization of subcritical CO in subcritical reactor 2 Washing 1000kg of crude aminopyrine under the following reaction conditions: temperature 291K, pressure 6.63X 11 6 Pa, in subcritical CO 2 Washing the residual extractant in the crude product;
after subcritical washing, dissolving aminopyrine in hot water at 99-111 ℃ to obtain an aminopyrine water solution, wherein the using amount of the hot water is 1.1 times of the mass of the crude aminopyrine product; keeping the water temperature at 91 ℃, sending the aminopyrine water solution into a continuous high-speed tubular centrifuge for high-speed centrifugation at the rotating speed of 31111r/min, collecting supernatant, concentrating, cooling, crystallizing at 65 ℃, and cooling to below 4 ℃ for solid-liquid separation to obtain refined crude material;
putting the refined crude product into a refining tank, adding 911kg of ethanol and 21kg of activated carbon, heating the steam in the interlayer of the refining tank to 79 ℃, preserving the heat at 92 ℃, and decoloring for 2 hours; after the decolorization is finished, opening nitrogen in a refining tank, filtering the hot activated carbon by using a ceramic membrane with the aperture of 1.1 mu m, pressing the filtrate into a crystallizing tank, cooling to 61 ℃ for crystallization, cooling to 11 ℃ for centrifugation to obtain a product; the crystallization rate was 72.4%, and the purity of the obtained purified aminopyrine was 95.9%.
Example 6
Utilization of subcritical CO in subcritical reactor 2 Washing 1000kg of crude aminopyrine under the following reaction conditions: temperature 311K, pressure 5.51X 11 6 PaBy subcritical CO 2 Washing the residual extractant in the crude product;
after subcritical washing, dissolving aminopyrine with hot water at 99-111 ℃ to obtain an aminopyrine water solution, wherein the using amount of the hot water is 1.5 times of the mass of the crude aminopyrine product; keeping the water temperature at 96 ℃, sending the aminopyrine water solution into a continuous high-speed tubular centrifuge for high-speed centrifugation at the rotating speed of 31111r/min, collecting supernatant, concentrating, cooling, crystallizing at 67 ℃, cooling to 5 ℃ and carrying out solid-liquid separation to obtain a refined crude product;
putting the obtained refined crude product into a refining tank, adding 1111kg of ethanol and 31kg of activated carbon, starting steam in an interlayer of the refining tank, heating to 79 ℃, keeping the temperature at 95 ℃, and decoloring for 2.5 hours; after the decolorization is finished, opening nitrogen in a refining tank, filtering the hot activated carbon by using a ceramic membrane with the aperture of 1.17 mu m, pressing the filtrate into a crystallizing tank, cooling to 55 ℃ for crystallization, cooling to 5 ℃ for centrifugation to obtain a product; the crystallization rate was 66.2%, and the purity of the obtained purified aminopyrine was 99.6%.
The foregoing is directed to preferred embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow. However, any simple modification, equivalent change and modification of the above embodiments according to the technical essence of the present invention are within the protection scope of the technical solution of the present invention.
Claims (10)
1. A process for refining a crude aminopyrine product is characterized by comprising the following steps:
1) first, subcritical CO is utilized in a subcritical reactor 2 Washing the crude aminopyrine product with subcritical CO 2 Washing the residual extractant in the crude product;
2) after subcritical washing, dissolving aminopyrine in hot water at 99-111 ℃ to obtain an aminopyrine water solution, sending the aminopyrine water solution into a centrifugal machine under the condition of heat preservation for high-speed centrifugation, collecting supernatant, and concentrating, cooling, crystallizing and carrying out solid-liquid separation on the supernatant to obtain a refined crude material;
3) mixing the refined crude material, ethanol and active carbon, heating for refluxing, filtering with membrane to obtain filtrate, cooling, crystallizing, and performing solid-liquid separation to obtain refined product.
2. The process for refining the crude aminopyrine according to claim 1, wherein:
subcritical CO described in step 1) 2 The washing reaction conditions were: the temperature is less than 314K, and the pressure is less than 7.39 multiplied by 11 6 Pa。
3. The process for refining the crude aminopyrine according to claim 1, wherein:
the centrifugal machine in the step 2) is a continuous high-speed tubular centrifugal machine, and the rotating speed of the centrifugal machine is 25111 r/min-31111 r/min.
4. The process for refining the crude aminopyrine according to claim 1, wherein:
the using amount of the hot water in the step 2) is 1.9-1.1 times of the mass of the crude aminopyrine product.
5. The process for refining the crude aminopyrine according to claim 1, wherein:
the filtering membrane used for the membrane filtration in the step 3) is a ceramic membrane, and the aperture of the ceramic membrane is 1.15-1.1 mu m.
6. The process for refining the crude aminopyrine according to claim 1, wherein:
the mass ratio of the refined crude material, the ethanol and the activated carbon in the step 3) is 1: 1.7-1.9: 1.11 to 1.12.
7. The process for refining the crude aminopyrine according to claim 1, wherein:
the heat preservation condition of the step 2) is to keep the aminopyrine water solution at 91-99 ℃.
8. The process for refining the crude aminopyrine according to claim 1, wherein:
the crystallization temperature in the step 2) is 65-71 ℃; and cooling to below 11 ℃ for solid-liquid separation.
9. The process for refining the crude aminopyrine according to claim 1, wherein:
the heating reflux in the step 3) is reflux after heating to 79-92 ℃, and the time of reflux decoloring is 2-3 hours.
10. The process for refining the crude aminopyrine according to claim 1, wherein:
the crystallization temperature in the step 3) is 51-61 ℃; and cooling to below 11 ℃ for solid-liquid separation.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101357903A (en) * | 2008-09-05 | 2009-02-04 | 山东新华制药股份有限公司 | Novel technique for preparing 4-formyl amino antipyrine |
| CN101891683A (en) * | 2010-07-22 | 2010-11-24 | 河北冀衡（集团）药业有限公司 | Aminopyrine production method |
| CN110713461A (en) * | 2019-11-01 | 2020-01-21 | 山东新华制药股份有限公司 | Method for refining aminopyrine crude product |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101357903A (en) * | 2008-09-05 | 2009-02-04 | 山东新华制药股份有限公司 | Novel technique for preparing 4-formyl amino antipyrine |
| CN101891683A (en) * | 2010-07-22 | 2010-11-24 | 河北冀衡（集团）药业有限公司 | Aminopyrine production method |
| CN110713461A (en) * | 2019-11-01 | 2020-01-21 | 山东新华制药股份有限公司 | Method for refining aminopyrine crude product |
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