CN102408351A - Crystallization treatment process of paracetamol acylation material liquid - Google Patents
Crystallization treatment process of paracetamol acylation material liquid Download PDFInfo
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- CN102408351A CN102408351A CN2011102874054A CN201110287405A CN102408351A CN 102408351 A CN102408351 A CN 102408351A CN 2011102874054 A CN2011102874054 A CN 2011102874054A CN 201110287405 A CN201110287405 A CN 201110287405A CN 102408351 A CN102408351 A CN 102408351A
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Abstract
The invention relates to a crystallization treatment process of paracetamol acylation material liquid, which is characterized in that the process comprises the following steps of: a preheating step for preheating a crystallization container; and a crystallization treatment step for introducing the acylation material liquid into the crystallization container and performing crystallization treatment of the acylation material liquid. Through preheating the crystallization container to a specified temperature, the impact to the bottom of the crystallization container caused by the material liquid of the high-temperature acylation material is effectively avoided; the generation of phenomena of porcelain crack and caking is solved; the service life of the equipment is prolonged; the crystal form of the crystallized material is protected favorably; the generation of powder material is reduced; and the product quality is improved.
Description
Technical field
The present invention relates to a kind of crystallization treatment process, relate in particular to the crystallization treatment process (being the crystallization treatment process of PARACETAMOL BP98 acidylate feed liquid) of the acidylate feed liquid in a kind of PARACETAMOL BP98 production process.
Background technology
PARA AMINOPHENOL and Glacial acetic acid min. 99.5 add the acidylate still, 140 ℃ of following acidylates after the proportion container batching; In the acylation process; Have water and be evaporated, and water can take a part of acetic acid (following steaming acid) when steaming out of, steam and need the acidylate material be carried out crystallization after acid finishes.
At present, in the production process of PARACETAMOL BP98, carry out acidylate at PARA AMINOPHENOL and Glacial acetic acid min. 99.5 and steam after acid finishes; Although can directly carry out decrease temperature crystalline at the acidylate jar, and then spinning in addition, the time that words in that event take the acidylate jar will increase; This can have influence on the carrying out of the acylation reaction of next batch material; In order to accelerate the working cycle of material, improve output, so select for use two jars to carry out acidylate and crystallization respectively.Promptly in order not take acidylate jar resource, acylation reaction with steam after sour process accomplishes, acidylate is steamed the acid back gained feed liquid (below be called the acidylate feed liquid) that finishes puts into another enamel reactor (being called crystallizer again) and carry out crystallization reaction; In this reaction process; Because the temperature of acidylate feed liquid reaches 130 ℃, and the temperature of crystallizer is lower,, pyritous acidylate feed liquid differs bigger crystallization tank skin or bottom if running into the temperature difference; The acidylate feed liquid can appear because of the phenomenon of Quench at crystallization tank skin or bottom caking; Cause the whole crystallization crystal formation of product undesirable, and the crystallization tank skin perhaps also can sudden and violent porcelain phenomenon, the work-ing life of reducing equipment thus occur because of receiving violent thermal shocking in its bottom easily; In the place that sudden and violent porcelain occurs; Contained acid can be immersed sudden and violent porcelain point and crystallizer (iron enamel pot) is corroded in the acidylate feed liquid, as can not in time finding and repair sudden and violent porcelain part, the tank body at sudden and violent porcelain place will be corroded and the acidylate feed liquid that causes being placed it in is oozed out or chuck in the acidylate feed liquid of circulatory mediator entering crystallizer in; Influence the quality of crystallization material, more serious words cause crystallizer to be scrapped.
Summary of the invention
In order to address this problem; Contriver of the present invention had once expected adopting the method for managing to reduce the acidylate feed temperature, thereby such as avoiding the acidylate feed liquid by the appearance of Quench caking or the sudden and violent porcelain phenomenon of crystallizer quilt through cryogenic liquid is mixed the temperature that reduces the acidylate feed liquid with the acidylate feed liquid.
But; Adopt cryogenic liquid and acidylate feed liquid method of mixing also to have following problem; Because the acidylate feed liquid is the intermediate product that is used to make the medicine PARACETAMOL BP98, the cryogenic liquid that is used for reducing the acidylate feed liquid need definitely guarantee can not bring new composition (impurity or impurity element), even and this cryogenic liquid can not bring new composition; But, bring too many trouble also can for operations such as follow-up crystallization, spinning because this cryogenic liquid has diluted the acidylate feed liquid.
In addition; Owing to consider operations such as follow-up crystallization, spinning; The cryogenic liquid that is used for reducing the acidylate feed liquid can unrestrictedly not add, and therefore can not the acidylate feed liquid be reduced to fully the temperature near crystallizer, therefore; Even be lowered some temperature, but the temperature head between acidylate feed liquid and the crystallizer still might bring detrimentally affect perhaps to cause the sudden and violent porcelain of crystallizer to the crystallization crystal formation of acidylate feed liquid.In a word; Pyritous acidylate material gentlier, can cause very big influence to the crystal formation of equipment and material to the thermal shocking of crystallizer; Can cause crystallizer to be scrapped when serious can not use again; Feed liquid in it can occur that little hole makes cooling medium in feed liquid and the chuck such as recirculated water mixes because of the tank body seriously corroded, influences the quality of crystallization material, and then the yield of reduction PARACETAMOL BP98.
For solve the feed liquid that exists in the prior art caking at the bottom of jar maybe and to the damage of equipment, the huge thermal shocking of the acidylate material of avoiding heat at the bottom of to jar prolongs work-ing life of equipment, improves the crystallization crystal formation purity of acidylate material, the spy has proposed the present invention.
The present invention provides a kind of crystallization treatment process of acidylate feed liquid, it is characterized in that, this process may further comprise the steps: the pre-heating step that crystallisation vessel is carried out preheating; With in said crystallisation vessel, import said acidylate feed liquid and make said acidylate feed liquid carry out the crystallization treatment step of crystallization treatment.
In the crystallization treatment process of above-mentioned acidylate feed liquid, preferred, before said pre-heating step, also comprise: the shop fixtures acid that in said crystallisation vessel, adds shop fixtures acid adds step.
In the crystallization treatment process of above-mentioned acidylate feed liquid, preferred, said shop fixtures acid is dilute acetic acid.
In the crystallization treatment process of above-mentioned acidylate feed liquid, preferred, the acetate concentration of said dilute acetic acid is 40%～50%.
In the crystallization treatment process of above-mentioned acidylate feed liquid, preferred, said dilute acetic acid is the by-product acid that acidylate is steamed sour process gained.
In the crystallization treatment process of above-mentioned acidylate feed liquid, preferred, in said pre-heating step, utilize the steam of first specified temperature that said crystallisation vessel is carried out preheating, be preheating to second specified temperature up to said crystallisation vessel.
In the crystallization treatment process of above-mentioned acidylate feed liquid, preferred, said first specified temperature is 140～175 ℃, and said second specified temperature is 60～80 ℃, and more preferably said first specified temperature is 150～160 ℃.In the crystallization treatment process of above-mentioned acidylate feed liquid, preferred, said steam is water vapour.
In the crystallization treatment process of above-mentioned acidylate feed liquid, preferred, utilize heat-eliminating medium that said crystallisation vessel is lowered the temperature in the said crystallization treatment step.
In the crystallization treatment process of above-mentioned acidylate feed liquid, preferred, in said crystallization treatment step, in said crystallisation vessel, import said acidylate feed liquid while stir.
In the crystallization treatment process of above-mentioned acidylate feed liquid, preferred, said crystallisation vessel drops to 20～30 ℃ of preparations and carries out spinning.
In the crystallization treatment process of above-mentioned acidylate feed liquid, said steam or said heat-eliminating medium all are in the peripheral chuck space that is provided with of crystallisation vessel, to flow.
Through adding dilute acetic acid or make crystallizer be preheating to specified temperature in advance to crystallizer in advance; Avoided of the impact of the feed liquid of high temperature acidylate material effectively to pot bottom; Solve the generation of sudden and violent porcelain and caking phenomenon, prolonged the work-ing life of equipment, advantageously protected the crystal formation of crystallized stock; Reduce the generation of powder, improved the quality of finished product.
Embodiment
In order to solve the possible detrimentally affect that the temperature difference between the acidylate feed liquid and crystallisation vessel is brought in the prior art, contriver of the present invention etc. have proposed following technical scheme.
Embodiment 1
As first embodiment of the present invention, its technical essential is exactly before the acidylate feed liquid being put into crystallisation vessel (often use crystallizer or be crystallization kettle as this crystallisation vessel in actual production), to improve the temperature of crystallisation vessel.
The disadvantageous effect of bringing for fear of the excessive temperature differentials of acidylate feed liquid and crystallisation vessel; The temperature of considering the acidylate feed liquid is about 130～140 ℃; Crystallisation vessel is preheating to about 60～80 ℃, and then the acidylate material is put into crystallisation vessel carry out decrease temperature crystalline.
Why select the temperature of crystallisation vessel is heated to 60～80 ℃; Be from following consideration: because the acidylate feed liquid begins to separate out the crystalline critical temperature about 85 ℃; If the preheating temperature of crystallisation vessel is lower than 60 ℃, when the lower tank skin of the acidylate feed liquid and the temperature of heat or shop fixtures acid began to contact, the temperature of partially acylated feed liquid will be lower than feed liquid rapidly and separate out the crystalline critical temperature; Will in cold tank skin or bottom liquid, form crystal like this; This crystal is because crystallization is rapid, and formed crystal is that soft junction is brilliant, wherein can comprise a part of impurity; This can cause adverse influence to the quality of product, so general the selection is heated to crystallisation vessel more than 60 ℃.If preheating temperature too high (greater than 80 ℃); Although further dwindled the temperature difference, can be to acidylate feed liquid deleterious impact, Heating temperature is high more; Needed quantity of steam will increase; And the completion needed TRT of preheating is also more and more longer, can the consumption and the production schedule of product be impacted like this, so preheating temperature generally also need not be above 80 ℃.
As the acidylate crystallisation vessel is preheating to the method about 60～80 ℃; Except traditional various well heaters that utilize are heated to crystallisation vessel the method for specified temperature; The present inventor has also expected utilizing the chuck that is arranged on the crystallisation vessel periphery, comes the preheating crystallisation vessel through the mode that in chuck, imports high-temperature steam.Be specially; Chuck (space between the endothelium of chuck and the outer wall of crystallisation vessel constitutes the chuck space) can be set at the outer part of crystallisation vessel; Through the high-temperature vapour of importing high-temperature steam in the chuck space of this chuck such as 120～175 ℃; Preferably 140～175 ℃ high-temperature vapour, particularly 150～160 ℃ high-temperature vapour, and preferred above-mentioned high-temperature steam is a high-temperature vapor; The heat passage temperature of utilizing high-temperature vapour to contact with the outer wall of crystallisation vessel to be brought of crystallisation vessel outer wall and bottom that makes rises to specified temperature, such as crystallisation vessel is preheating to about 70 ℃.Do not have specific restriction about steam mobile in chuck, such as being the top of the import of steam at chuck, by the pipeline input, tail gas is exported by the bottom, also can act in a diametrically opposite way, and particular case according to actual needs calmly.
Acidylate feed liquid crystallization method based on this technical essential is following.
Specifically the step of whole crystallization treatment process, comprises following process:
The first step before the acidylate feed liquid gets into crystallisation vessel, utilizes high-temperature steam that crystallisation vessel is carried out preheating, arrives specified temperature up to the crystallisation vessel preheating; Generally speaking, crystallisation vessel is preheating to 60～80 ℃ and gets final product.
In second step, in crystallisation vessel, import pyritous acidylate feed liquid.When importing the acidylate feed liquid; Can turn on agitator stir; Purpose is for the feed liquid of putting into crystallisation vessel can be mixed from start to finish; Can not acidylate feed liquid local temperature in the time period of blowing inhomogeneous and cause the lower part of temperature too early separate out crystal, thereby influence the total quality of product.
In the 3rd step, open circulating cooling medium crystallisation vessel is lowered the temperature; As this circulating cooling medium; From economical and practical angle, generally select for use recirculated water as medium, also can use salt solution as cooled circulated medium when particular requirement is arranged, what temperature reduced but salt solution is lowered the temperature is too fast; May certain influence be arranged to the crystalline crystal formation; And can strengthen the refrigerated load, so do not adopt generally speaking, adopt when just speed of cooling being had higher requirements.In addition, circulating cooling medium also can carry out through the chuck space the cooling of crystallisation vessel, such as the bottom entering chuck of recirculated water from chuck, from the top output of chuck.
In the 4th step, when the temperature of crystallisation vessel drops to specified temperature (such as 25 ± 5 ℃), prepare to carry out spinning and handle.
Embodiment 2
Though in above-mentioned embodiment 1, the jar temperature of crystallisation vessel has totally been reached about 60～80 ℃ through preheating; Dwindled much with the temperature spread of acidylate feed liquid; Effectively having alleviated the temperature difference destroys feed liquid crystallization crystal formation and crystallisation vessel enamelled; But still might bring detrimentally affect, this is because being used for the steam of preheating is to get into the chuck space by the top that is arranged on the outside chuck of crystallisation vessel, whole tank body be heated and inhomogeneous; The pot bottom temperature does not probably reach 60～80 ℃, and this problem of mentioning in the background technology can still might occur being similar in the crystallization reaction that carries out subsequently.
Because the acidylate material temperature is up to 130～140 ℃, and the pot bottom temperature of crystallizer possibly not reach 60～80 ℃, so pot bottom still receives stronger thermal shocking when pyritous acidylate material feed liquid arrives pot bottom rapidly.The pyritous feed liquid runs into temperature jar on the low side during the end; Feed liquid still might occur and form the phenomenon of bulk at pot bottom; Bring detrimentally affect for the crystallization crystal formation of acidylate material; And the cryogenic jar end, receive the thermal shocking of high temperature feed liquid, also still may produce sudden and violent porcelain, reduces the work-ing life of equipment.
The detrimentally affect that possibly exist for further elimination; Contriver of the present invention has carried out further improvement to the method for embodiment; A kind of new acidylate post crystallization treatment process has been proposed; Simply, be exactly to add acetic acid in the bottom of crystallizer as shop fixtures acid, utilize acetic acid to improve thermal shocking that the huge temperature difference between crystallizer and the high temperature acidylate material brings detrimentally affect to acidylate material and crystallizer both sides.
Specifically step based on the whole crystallization treatment process of embodiment two, comprises following process:
The first step before the acidylate feed liquid adds crystallizer, adds a certain amount of acetic acid as shop fixtures acid in crystallizer.
Second step, utilize high-temperature steam that crystallizer is carried out preheating, arrive specified temperature up to the crystallizer preheating; Generally speaking, crystallizer is preheating to 60～80 ℃ and gets final product.
The 3rd step, the feed liquid of importing high temperature acidylate material in crystallizer.When importing feed liquid, can turn on agitator stir.
In the 4th step, utilize circulating cooling medium that crystallizer is lowered the temperature; As this circulating cooling medium, can select for use recirculated water as medium, identically with embodiment 1 in particular cases also can use salt solution.
In the 5th step, when the temperature of crystallizer drops to specified temperature (20～30 ℃), prepare to carry out spinning and handle.
Acetic acid as shop fixtures acid; Consider the concentration of acidylate feed liquid and whether help blowing centrifugal angle; Generally as far as possible need not dense acetic acid; But preferentially select the dilute acetic acid of acetate concentration between 40%～50% for use; As this kind dilute acetic acid, both can be the industrial dilute acetic acid of selling on the market (collecting in the Paracetamol USP23,BP98 production process), also can be in our factory's PARACETAMOL BP98 production process acylation reaction adopt the collected by-product acid of sour process (acetate concentration approximately be more than 45% below 50%).In actual production; Set out in line with angle economical and practical, that gather materials on the spot; The preferred dilute acetic acid (being by-product acid) that uses acidylate to steam, and if select for use the acidylate of crystallization treatment process front to steam dilute acetic acid that sour process obtains to also have a big advantage be can not bring new impurity.
As the amount that joins the acetic acid in the crystallizer; Can be decided according to the actual requirements by the technician, simply, the amount that adds dilute acetic acid is the dosage decision during according to acidylate; Be exactly that acidylate is steamed the water yield that the sour water yield that steams deducts acylation reaction self generation specifically; Amount to into dilute acetic acid again, deduct the diluted acid amount of flushing acidylate jar then, just obtain the amount of shop fixtures acid.
Utilizing high-temperature steam crystallizer to be carried out under the technical scheme prerequisite of preheating; If at the bottom of jar, have a certain amount of by the dilute acetic acid of preheating; Even can drop to the bottom apace in the acidylate feed liquid; But because the acidylate feed liquid is not directly to contact the temperature more jar end on the low side relatively; Though but the dilute acetic acid as shop fixtures acid also on the low side relatively with temperature but preheating contacts; Therefore quick fallen acidylate feed liquid is dissolved in shop fixtures acid the inside rapidly, and condense into solid can not resembling when contact with a bigger jar end of the temperature difference, has further improved the generation of phenomenons such as feed liquid caking that the temperature difference at high temperature acidylate feed liquid and jar end possibly cause and the sudden and violent porcelain in the jar end.
About the supplementary notes of this embodiment,, and in embodiment 2, do not carry out same elaboration in embodiment 1 although some parameters are discussed; The other parameter is discussed in embodiment 1; And in embodiment 2, do not discuss, but these parameters are general in the middle of embodiment 1,2, promptly as long as the requirement of technology identical parameters just can be identical; Just, just omit for fear of unnecessary repetition.
Provide a specific embodiment with regard to above-mentioned embodiment below.
Half a hour before the acidylate blowing, in crystallizer, add a certain amount of dilute acetic acid earlier, such as 200-300L; Open jacket steam then crystallizer is carried out preheating, reach 70 ℃, open crystallizer then and stir until the jar temperature; Feed liquid with the acidylate material imports crystallizer then, and when feed liquid was stirred, open cycle water began crystallizer is lowered the temperature; Feed liquid is carried out crystallization in this process; When the temperature of crystallizer drops to when requiring 20～30 ℃, prepare feed liquid is carried out spinning with whizzer, isolate solid materials.
After accomplishing above-mentioned crystallization treatment process; Observe the jar end of crystallizer and the solid crystal material that obtains; The result finds not occur in the whole process of production phenomenon of feed liquid at crystallization tank skin or bottom caking; Sudden and violent porcelain phenomenon does not appear in a jar end yet simultaneously, and the crystal formation of solid crystal material is also very normal, has reached goal of the invention well.
The invention effect
Owing to added dilute acetic acid to crystallizer in advance, avoided the impact of thermal material effectively to pot bottom, solved the generation of sudden and violent porcelain and knot tank skin phenomenon, prolonged the work-ing life of equipment, reduced the working strength that the workman is dissolved tank skin.Advantageously protect the crystal formation of material in addition, reduced the generation of powder, improved the quality of finished product.
Claims (10)
1. the crystallization treatment process of a PARACETAMOL BP98 acidylate feed liquid is characterized in that, this process may further comprise the steps:
Crystallisation vessel is carried out the pre-heating step of preheating; With
In said crystallisation vessel, import said acidylate feed liquid and make said acidylate feed liquid carry out the crystallization treatment step of crystallization treatment.
2. the crystallization treatment process of PARACETAMOL BP98 acidylate feed liquid as claimed in claim 1 is characterized in that;
Before said pre-heating step, also comprise: the shop fixtures acid that in said crystallisation vessel, adds shop fixtures acid adds step.
3. the crystallization treatment process of PARACETAMOL BP98 acidylate feed liquid as claimed in claim 2 is characterized in that;
Said shop fixtures acid is dilute acetic acid.
4. the crystallization treatment process of PARACETAMOL BP98 acidylate feed liquid as claimed in claim 3 is characterized in that;
The acetate concentration of said dilute acetic acid is 40%～50%.
5. the crystallization treatment process of PARACETAMOL BP98 acidylate feed liquid as claimed in claim 2 is characterized in that;
Said dilute acetic acid is the by-product acid that acidylate is steamed sour process gained.
6. the crystallization treatment process of PARACETAMOL BP98 acidylate feed liquid as claimed in claim 1 is characterized in that;
In said pre-heating step, utilize the steam of first specified temperature that said crystallisation vessel is carried out preheating, be preheating to second specified temperature up to said crystallisation vessel.
7. the crystallization treatment process of PARACETAMOL BP98 acidylate feed liquid as claimed in claim 6 is characterized in that;
Said first specified temperature is 140～175 ℃, and said second specified temperature is 60～80 ℃, and said steam is water vapour.
8. the crystallization treatment process of PARACETAMOL BP98 acidylate feed liquid as claimed in claim 1 is characterized in that;
Utilize circulating cooling medium that said crystallisation vessel is cooled to 20～30 ℃ in the said crystallization treatment step.
9. the crystallization treatment process of PARACETAMOL BP98 acidylate feed liquid as claimed in claim 1 is characterized in that;
In said crystallization treatment step, in said crystallisation vessel, import said acidylate feed liquid while stir.
10. the crystallization treatment process of PARACETAMOL BP98 acidylate feed liquid as claimed in claim 6 is characterized in that;
Said steam carries out preheating through in the chuck of the periphery of said crystallisation vessel setting, flowing to said crystallisation vessel.
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Citations (3)
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| CN1434026A (en) * | 2003-02-11 | 2003-08-06 | 中国石化集团南京化工厂 | Process for prepraring p-acetpamidophenol |
| CN1569819A (en) * | 2004-04-30 | 2005-01-26 | 河北工业大学 | Process for synthesizing paracetamol |
| CN102060729A (en) * | 2010-12-28 | 2011-05-18 | 刘瑞平 | Method for continuously and efficiently preparing p-acetamidophenol |
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2011
- 2011-09-26 CN CN201110287405.4A patent/CN102408351B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1434026A (en) * | 2003-02-11 | 2003-08-06 | 中国石化集团南京化工厂 | Process for prepraring p-acetpamidophenol |
| CN1569819A (en) * | 2004-04-30 | 2005-01-26 | 河北工业大学 | Process for synthesizing paracetamol |
| CN102060729A (en) * | 2010-12-28 | 2011-05-18 | 刘瑞平 | Method for continuously and efficiently preparing p-acetamidophenol |
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| 张勇等: "两种对氨基酚生产扑热息痛的收率对比", 《广东化工》, vol. 37, no. 8, 25 August 2010 (2010-08-25), pages 111 - 120 * |
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Address after: 053000 No.1, Weiwu street, high tech Zone, Hengshui City, Hebei Province Patentee after: Hebei Jiheng Pharmaceutical Co.,Ltd. Address before: 053000 No.368 Jianshe North Street, Hengshui City, Hebei Province Patentee before: HEBEI JIHENG (Group) PHARMACEUTICAL Co.,Ltd. |