CN109678682A - A kind of technique absorbing pinacoline production tail gas reproduction pinacoline using concentrated hydrochloric acid - Google Patents
A kind of technique absorbing pinacoline production tail gas reproduction pinacoline using concentrated hydrochloric acid Download PDFInfo
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- CN109678682A CN109678682A CN201811508770.1A CN201811508770A CN109678682A CN 109678682 A CN109678682 A CN 109678682A CN 201811508770 A CN201811508770 A CN 201811508770A CN 109678682 A CN109678682 A CN 109678682A
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- pinacoline
- hydrochloric acid
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
- C07C45/78—Separation; Purification; Stabilisation; Use of additives
- C07C45/81—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation
- C07C45/82—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation by distillation
- C07C45/84—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation by distillation by azeotropic distillation
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Abstract
The present invention relates to a kind of techniques for absorbing pinacoline production tail gas reproduction pinacoline using concentrated hydrochloric acid, it is characterised in that: the specific process is as follows: S1: concentrated hydrochloric acid pre-cooling and enrichment；The preparation of S2:2- chlorine isopentane；S3: the synthesis of pinacoline；S4: decoloration；Pinacoline product purity in the present invention using this method production is high, it ensure that the color of product, the tail gas generated in production can repeated recycling utilize into the production of pinacoline, really realize green production, furthermore, the reaction time can be effectively shortened by the pre-cooling of concentrated hydrochloric acid, improve production efficiency, preparation process of the invention, simple process, it prepares pinacoline to generate without spent acid in the process, solves the pressure of environment；Meanwhile after rectifying, increase decoloration process, avoid being mixed with hydrochloric acid in product, on the basis of guaranteeing product purity, can also guarantee the color of product, and then purity can be prepared and reach >=98%, and colourless pinacoline product.
Description
Technical field
Pinacoline production tail gas is absorbed the present invention relates to pinacoline production field more particularly to a kind of utilization concentrated hydrochloric acid to regenerate
The technique for producing pinacoline.
Background technique
Pinacoline i.e. 3,3- dimethyl-2-butanone, be produce triadimefon, the important source material of the pesticides such as multiple-effect and medicine,
The intermediate of a variety of fine chemical products such as dyestuff.The synthetic method of pinacoline is more, and rearrangement method is using pinacol as raw material, in acid
Property environment in dehydrative rearrangement generate [guizhou chemical industry 2,006 4 (31): 4-6].The method deficiency be raw material pinacol source it is difficult and
Severe reaction conditions.Oxidizing process with 2,3- dimethyl -2- butylene be raw material, with organic peroxide acid or hydrogen peroxide as oxidant
Oxidation, then reset to obtain pinacoline [the ring-opening reaction research Hebei Normal University of Liu Yuheng epoxides, 2009].It should
The shortcomings that method is raw material 2, and 3- dimethyl -2- butylene limited source, process conditions are harsh, process flow is long etc..
Iso-amylene method first generates tert-amyl chloride using iso-amylene as raw material with hydrochloric acid or sulfuric acid reaction, then anti-with hydration formaldehyde
Pinacoline [Hunan chemical industry 1992 (3): 42-47] should be generated.This method advantage is that iso-amylene raw material is easy to get, and yield is higher,
The disadvantage is that using a large amount of inorganic acid and generating largely containing the spent acid of plurality of impurities.
Chinese invention patent application number: 99114409 .0 disclose a kind of new method for preparing pinacoline, different with industry
Amylene is that phosphorus trichloride is added dropwise in raw material in acid medium and iso-amylene carries out addition, obtains intermediate.Intermediate is in counterflow condition
Under, formalin progress condensation reaction is added dropwise and obtains pinacoline [CN1286242A].The method is the disadvantage is that still without solving spent acid
The problem of, yield is lower.
Li Zengguang, Huanghai Sea army et al. are instilled in hydrochloric acid with sulfuric acid or phosphoric acid first in patent " which ketone process for cleanly preparing "
Mixed acid is made, then using industrial iso-amylene as raw material, iso-amylene is added dropwise in mixing acid medium obtained, intermediate is made, it is intermediate
Paraformaldehyde, which is added portionwise, in body under reflux conditions carries out reaction and prepares pinacoline [CN102557905A].The method is the disadvantage is that still
Using a large amount of inorganic acids and generate largely containing the spent acid of plurality of impurities.
It is above-mentioned to generate a large amount of spent acid by the method for raw material of iso-amylene, huge pressure is caused to environment, while
Make increased costs.
For above-mentioned phenomenon, patent CN 105503550A discloses a kind of environment-friendly preparation method thereof of pinacoline, technique step
It is rapid as follows: slowly iso-amylene to be added dropwise in technical hydrochloric acid under agitation first, isolated upper layer intermediate tertiary pentyl
Chlorine, lower layer's acid solution are synthesized for lower step and are used；Obtained tert-amyl chloride is put in reactor, be added methanol or pinacoline make it is molten
Agent is slowly added to metaformaldehyde under stirring condition in batches, is heated to flowing back, and hydrogen chloride that reaction generates is imported what step obtained
In acid solution；Stop reaction, liquid in reactor is down to room temperature naturally, obtaining homogeneous substance is pinacoline crude product, simultaneously
The hydrochloric acid arrived is used for synthesis next time, crude product pinacoline Chun Du≤98% after rectifying, and the invented technology is simple, and where is preparation frequency
Ketone process is generated without waste liquid, solves the pressure of environment, but there are still certain defects for the preparation method: during the preparation process,
Using technical hydrochloric acid, and it is often mixed with some frerrous chlorides in technical hydrochloric acid and makes technical hydrochloric acid presentation yellowish, in pinacoline
Crude product pinacoline can be mixed with certain hydrochloric acid in production, and pinacoline is colorless product, but since the presence of technical hydrochloric acid makes
Product yellowing, influences product color.
Summary of the invention
Pinacoline production tail gas reproduction frequency is absorbed using concentrated hydrochloric acid the technical problem to be solved in the present invention is to provide a kind of
The technique of which ketone is able to solve in pinacoline production and absorbs by-product hydrochloric acid and iso-amylene using water, and iso-amylene is not soluble in water, water
The reluctant problem of the hydrochloric acid of absorption；
In order to solve the above technical problems, the technical solution of the present invention is as follows: a kind of absorb pinacoline production tail gas again using concentrated hydrochloric acid
The technique for producing pinacoline, innovative point are: the specific process is as follows:
S1: the concentrated hydrochloric acid of 31% concentration concentrated hydrochloric acid pre-cooling and enrichment: is cooled to 0 DEG C -3 DEG C by chilled brine in advance；Absorb pinacoline
The isopentene and hydrochloric acid of the generation of production, isopentene react with concentrated hydrochloric acid, and the concentrated hydrochloric acid of 31% concentration is dense after being passed through hydrochloric acid
Degree is promoted；
The preparation of S2:2- chlorine isopentane: the concentrated hydrochloric acid after concentration in S1 is promoted is cooled to -5 DEG C~0 DEG C, delays under stirring condition
The slow iso-amylene for being added dropwise 0 DEG C~3 DEG C, is added dropwise, and stirs 1~3 hour, generates 2- chlorine isopentane；
S3: the synthesis of pinacoline: the 2- chlorine isopentane generated in step S2 is pumped into condensation reaction kettle by front pump, so
Stirring is opened afterwards, while slowly heating, when gas phase temperature reaches 70 DEG C~80 DEG C, start to be slowly added dropwise into condensation reaction kettle
Formaldehyde is added dropwise, and insulation reaction 1~2 hour, after reaction, cooling, stratification, upper layer crude product pinacoline entered 70
DEG C~80 DEG C of rectifier unit carries out rectifying, lower layer's acid solution is evacuated to spent acid distillation still and is fractionated；
S4: decoloration: the pinacoline after rectifying is sent into dedicated azeotropic point distillation decoloration device, in 100 DEG C~110 DEG C of condition
Lower progress decolorization 2~4 hours can obtain purity and reach >=98%, and colourless pinacoline product.
Further, the byproduct gas in the S2 includes hydrochloric acid and iso-amylene, and the hydrochloric acid is all made of with iso-amylene
The step of S1, carries out absorbing reaction.
Further, the hydrogen chloride that condensation reaction generates in the S3 is carried out in the concentrated hydrochloric acid into S1 by pipeline
The enrichment of concentrated hydrochloric acid.
Further, lower layer's acid solution of the step S3 is evacuated to spent acid distillation still, and water, and the volume ratio of acid solution and water is added
For 1:8,80 DEG C~100 DEG C at a temperature of be fractionated, the dilute hydrochloric acid after fractionation is pumped into hydrochloric acid pans, the crude product obtained to fractionation
Pinacoline carries out rectifying into 70 DEG C~80 DEG C of rectifier unit, after rectifying, repeats step S4 and decolourizes, finally, will decoloration
Pinacoline afterwards, which is sent to special-purpose dewatering device, to be carried out dehydrating, and can be obtained purity and be reached >=98%, and colourless pinacoline product.
The present invention has the advantages that
1) the pinacoline product purity in the present invention using this method production is high, ensure that the color of product, generates in production
Tail gas can repeated recycling utilize into the production of pinacoline, green production is really realized, in addition, passing through the pre- cold energy of concentrated hydrochloric acid
It enough effectively shortens the reaction time, improves production efficiency, preparation process of the invention, simple process prepares nothing during pinacoline
Spent acid generates, and solves the pressure of environment；Meanwhile after rectifying, increases decoloration process, avoid being mixed with hydrochloric acid in product, protect
On the basis of demonstrate,proving product purity, can also guarantee the color of product, and then purity can be prepared up to >=98%, and colourless frequency which
Ketone product.
Specific embodiment
The following examples can make professional and technical personnel that the present invention be more fully understood, but therefore not send out this
It is bright to be limited among the embodiment described range.
Embodiment 1:
A kind of technique absorbing pinacoline production tail gas reproduction pinacoline using concentrated hydrochloric acid, the specific process is as follows:
S1: the concentrated hydrochloric acid of 31% concentration concentrated hydrochloric acid pre-cooling and enrichment: is cooled to 0 DEG C -3 DEG C by chilled brine in advance；Absorb pinacoline
The isopentene and hydrochloric acid of the generation of production, isopentene react with concentrated hydrochloric acid, and the concentrated hydrochloric acid of 31% concentration is dense after being passed through hydrochloric acid
Degree is promoted, and the concentration of concentrated hydrochloric acid can be promoted to 33% after testing；
The preparation of S2:2- chlorine isopentane: the concentrated hydrochloric acid after concentration in S1 is promoted is cooled to -5 DEG C~0 DEG C, delays under stirring condition
The slow iso-amylene for being added dropwise 0 DEG C~3 DEG C, is added dropwise, and stirs 1~3 hour, generates 2- chlorine isopentane；
S3: the synthesis of pinacoline: the 2- chlorine isopentane generated in step S2 is pumped into condensation reaction kettle by front pump, so
Stirring is opened afterwards, while slowly heating, when gas phase temperature reaches 70 DEG C~80 DEG C, start to be slowly added dropwise into condensation reaction kettle
Formaldehyde is added dropwise, and insulation reaction 1~2 hour, after reaction, cooling, stratification, upper layer crude product pinacoline entered 70
DEG C~80 DEG C of rectifier unit carries out rectifying, lower layer's acid solution is evacuated to spent acid distillation still and is fractionated；
S4: decoloration: the pinacoline after rectifying is sent into dedicated azeotropic point distillation decoloration device, in 100 DEG C~110 DEG C of condition
Lower progress decolorization 2~4 hours can obtain purity and reach >=98%, and colourless pinacoline product.
The step of byproduct gas in S2 includes hydrochloric acid and iso-amylene, and the hydrochloric acid is all made of S1 with iso-amylene is inhaled
Receive reaction.
The hydrogen chloride that condensation reaction generates in S3 carries out the enrichment of concentrated hydrochloric acid by pipeline in the concentrated hydrochloric acid into S1.
Lower layer's acid solution of S3 is evacuated to spent acid distillation still, water is added, and acid solution and the volume ratio of water are 1:8,80 DEG C~100
Be fractionated at a temperature of DEG C, dilute hydrochloric acid after fractionation is pumped into hydrochloric acid pans, to the crude product pinacoline that fractionation obtains enter 70 DEG C~
80 DEG C of rectifier unit carries out rectifying, after rectifying, repeats step S4 and decolourizes, finally, sending the pinacoline after decoloration to special
It is carried out dehydrating with dehydration device, purity can be obtained and reach >=98%, and colourless pinacoline product.
It should be understood by those skilled in the art that the present invention is not limited to the above embodiments, above-described embodiment and explanation
It is merely illustrated the principles of the invention described in book, without departing from the spirit and scope of the present invention, the present invention also has
Various changes and modifications, these changes and improvements all fall within the protetion scope of the claimed invention.The claimed scope of the invention
It is defined by the appending claims and its equivalent thereof.
Claims (4)
1. a kind of technique for absorbing pinacoline production tail gas reproduction pinacoline using concentrated hydrochloric acid, it is characterised in that: concrete technology
It is as follows:
S1: the concentrated hydrochloric acid of 31% concentration concentrated hydrochloric acid pre-cooling and enrichment: is cooled to 0 DEG C -3 DEG C by chilled brine in advance；Absorb pinacoline
The isopentene and hydrochloric acid of the generation of production, isopentene react with concentrated hydrochloric acid, and the concentrated hydrochloric acid of 31% concentration is dense after being passed through hydrochloric acid
Degree is promoted；
The preparation of S2:2- chlorine isopentane: the concentrated hydrochloric acid after concentration in S1 is promoted is cooled to -5 DEG C~0 DEG C, delays under stirring condition
The slow iso-amylene for being added dropwise 0 DEG C~3 DEG C, is added dropwise, and stirs 1~3 hour, generates 2- chlorine isopentane；
S3: the synthesis of pinacoline: the 2- chlorine isopentane generated in step S2 is pumped into condensation reaction kettle by front pump, so
Stirring is opened afterwards, while slowly heating, when gas phase temperature reaches 70 DEG C~80 DEG C, start to be slowly added dropwise into condensation reaction kettle
Formaldehyde is added dropwise, and insulation reaction 1~2 hour, after reaction, cooling, stratification, upper layer crude product pinacoline entered 70
DEG C~80 DEG C of rectifier unit carries out rectifying, lower layer's acid solution is evacuated to spent acid distillation still and is fractionated；
S4: decoloration: the pinacoline after rectifying is sent into dedicated azeotropic point distillation decoloration device, in 100 DEG C~110 DEG C of condition
Lower progress decolorization 2~4 hours can obtain purity and reach >=98%, and colourless pinacoline product.
2. a kind of technique that pinacoline production tail gas reproduction pinacoline is absorbed using concentrated hydrochloric acid according to claim 1,
It is characterized by: the byproduct gas in the S2 includes hydrochloric acid and iso-amylene, the hydrochloric acid and iso-amylene are all made of the step of S1
It is rapid to carry out absorbing reaction.
3. a kind of technique that pinacoline production tail gas reproduction pinacoline is absorbed using concentrated hydrochloric acid according to claim 1,
It is characterized by: the hydrogen chloride that condensation reaction generates in the S3 carries out concentrated hydrochloric acid in the concentrated hydrochloric acid into S1 by pipeline
Enrichment.
4. a kind of technique that pinacoline production tail gas reproduction pinacoline is absorbed using concentrated hydrochloric acid according to claim 1,
It is characterized by: lower layer's acid solution of the step S3 is evacuated to spent acid distillation still, water is added, and acid solution and the volume ratio of water are 1:8,
80 DEG C~100 DEG C at a temperature of be fractionated, dilute hydrochloric acid after fractionation is pumped into hydrochloric acid pans, the crude product pinacoline obtained to fractionation
Rectifying is carried out into 70 DEG C~80 DEG C of rectifier units, after rectifying, step S4 is repeated and decolourizes, finally, by the frequency after decoloration
Which ketone, which is sent to special-purpose dewatering device, is carried out dehydrating, and can obtain purity and reach >=98%, and colourless pinacoline product.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110452108A (en) * | 2019-08-14 | 2019-11-15 | 南通鸿富达利化工有限公司 | A kind of pinacoline production product separating technique |
| CN111484401A (en) * | 2020-04-07 | 2020-08-04 | 南通利奥化工科技有限公司 | Production process for improving conversion rate of dichloropinacolone |
| CN113061076A (en) * | 2021-04-02 | 2021-07-02 | 开封银河日化有限责任公司 | Preparation method of chloro-tert-pentane |
| CN113717025A (en) * | 2021-08-10 | 2021-11-30 | 江苏七洲绿色化工股份有限公司 | Synthesis method of chloro-tert-pentane |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110452108A (en) * | 2019-08-14 | 2019-11-15 | 南通鸿富达利化工有限公司 | A kind of pinacoline production product separating technique |
| CN111484401A (en) * | 2020-04-07 | 2020-08-04 | 南通利奥化工科技有限公司 | Production process for improving conversion rate of dichloropinacolone |
| CN113061076A (en) * | 2021-04-02 | 2021-07-02 | 开封银河日化有限责任公司 | Preparation method of chloro-tert-pentane |
| CN113061076B (en) * | 2021-04-02 | 2023-09-26 | 开封银河日化有限责任公司 | Preparation method of chloroterpentane |
| CN113717025A (en) * | 2021-08-10 | 2021-11-30 | 江苏七洲绿色化工股份有限公司 | Synthesis method of chloro-tert-pentane |
| CN113717025B (en) * | 2021-08-10 | 2023-11-14 | 江苏七洲绿色化工股份有限公司 | Synthesis method of chloroterpentane |
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Application publication date: 20190426 |