CN107814362A - A kind of method and device that sulfuric acid is reclaimed from nitrating wasting acid - Google Patents
A kind of method and device that sulfuric acid is reclaimed from nitrating wasting acid Download PDFInfo
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- CN107814362A CN107814362A CN201711078832.5A CN201711078832A CN107814362A CN 107814362 A CN107814362 A CN 107814362A CN 201711078832 A CN201711078832 A CN 201711078832A CN 107814362 A CN107814362 A CN 107814362A
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- acid
- evaporator
- effect evaporator
- sulfuric acid
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B17/00—Sulfur; Compounds thereof
- C01B17/69—Sulfur trioxide; Sulfuric acid
- C01B17/90—Separation; Purification
- C01B17/94—Recovery from nitration acids
Abstract
The invention discloses a kind of method and device that sulfuric acid is reclaimed from nitrating wasting acid.Methods described comprises the following steps：Nitrating wasting acid adsorbs through polymeric adsorbent successively, decolourize and UF membrane obtains acid-bearing wastewater；The acid-bearing wastewater sequentially enters 1st effective evaporator A, 2nd effect evaporator, triple effect evaporator and four-effect evaporator and carries out steam step-by-step heating, that is, realizes the purpose that sulfuric acid is reclaimed from the nitrating wasting acid.The inventive method solves industrialization nitrating wasting acid and is difficult to reclaim high-concentration sulfuric acid, makes its cycling and reutilization, and in generally use and/or produces the problems of other byproducts.The technological process of the inventive method is simple, and cost is low, and product purity is high; the sulfuric acid that concentration is more than 96% can be directly obtained, for the rate of recovery of sulfuric acid up to more than 97%, the sulfuric acid of recovery is available for nitrification production technology to reuse; resource can both be circulated, efficiently utilized, again can environmental protection.
Description
Technical field
The present invention relates to a kind of method that sulfuric acid is reclaimed from nitrating wasting acid, belong to industrial waste acid process field
Background technology
2- nitro -4- acetyl-anisidines are production disperse dyes and medicine important intermediate 2- amino -4- acetyl
The intermediate product of aminoanisole, it is both at home and abroad raw material generally using paraphenetidine, through acylation, nitrification, reduction process life
Produce 2- amino -4- acetyl-anisidines.In nitrification process, p acetamidoanisol is nitrified using nitration mixture,
2- nitro -4- acetyl-anisidines are made through water washing, separation, this process can cause substantial amounts of acid pickle, containing highly concentrated
The sulfuric acid of degree and substantial amounts of aromatic compound.Wherein sulphuric acid is a strong corrosive, and aromatic compound has carcinogenic, cause mostly
Abnormal and mutagenic property, it is directly discharged in environment not only cause high risks to ecological environment and health, can also makes
Into the waste of resource.
At present, industrial spent acid processing is more using the side such as Waste Sulfuric Acid concentration, Pintsch process, extraction, neutralisation treatment, film process
Method, the improvement recovery of acid pickle is also very common in fine chemistry industry production caused by the mixed acid nitrification production of arene.In
In state patent application CN106276817A, Sinopec Group Wang Pei orchids and Zou Ningfen, 1,2- dichloros are utilized
Ethane is extracted to spent acid caused by 1,2,3- trichloro-benzenes nitrification, removes organic matter therein, spent acid then is subject into profit again
With.Though this method can effectively remove the organic matter in acid pickle, also contain a small amount of nitric acid, and sulfuric acid in the spent acid after processing
Concentration it is relatively low, it is impossible to be directly used in and nitrify again.Slowly women's headgear et al. is built in Chinese patent application CN105858627A to benzene homologues nitre
Change spent acid to be recycled, first the spent acid from benzene homologues nitration reaction process is mixed with activated carbon and carried out at decolouring
Spent acid after decolorization, is then added in batch reactive distillation tower by reason, adds potassium nitrate, certain temperature, pressure are entered below
Row border ring distillation operation, collection slip out liquid, i.e. recovered liquid.Add water into batch reactive distillation tower reactor again afterwards, and use hydrogen-oxygen
Change sodium regulation pH value, filter while hot, filtrate natural cooling separates out solid, i.e. potassium acid sulfate, and mother liquor carries out recovery.Though invention
Spent acid can effectively be utilized, but cannot be used for nitrification operation again, can not complete to recycle.Chinese patent application
Refined et al. the invention of CN104649910A willows《A kind of acid applies mechanically the method that serialization nitrification prepares 2,5- dichloronitrobenzenes》.Its
Middle nitrating wasting acid first extracts organic matter with paracide, while consumes residual nitric acid therein, after the waste acid concentration after extraction with
Nitric acid configures nitration mixture and nitrified for lower batch.In this invention, the concentration of concentrated vitriol can reach 90%.Chinese patent application
CN103214388A, Zhejiang Longsheng Chemicals Co., Ltd. invent《A kind of recoverying and utilizing method of nitrating wasting acid》, this hair
It is bright using nitrating wasting acid mother liquor caused by p acetamidoanisol and mixed acid nitrification as raw material, by being passed through ammonia or adding liquefied ammonia
Neutralization, cold filtration, organic matter separation, decolouring oxidation, condensing crystallizing producing ammonium sulfate byproduct, organic itrated compound of separation, which returns, to be used as
Raw material is nitrified, concentration condensing hot air furnace is used for the washing for nitrifying filter cake；Though effectively increasing nitration product yield, spent acid is realized
Comprehensive utilization of resources, but spent acid is nitrified the purpose recycled also without reaching.Chinese patent application CN102936002A
Positive virtue of leaf et al. is invented《The method and its application of high-purity sulphuric acid are reclaimed from 2,4,6- trinitrotoluene nitrating wasting acids》；Invention
Point out, rectifying stage by stage is carried out to TNT nitrating wasting acids using glass spring stuffing rectification column, constantly removes spent acid reclaimed water and big portion
Divide organic impurities, improve the concentration and purity of sulfuric acid, finally give high-purity sulphuric acid；This invention directly can obtain 98% it is high-purity
Sulfuric acid, retrieval of sulfuric acid rate are available for TNT nitration processes to recycle up to 90%；But such a process from glass spring due to being filled out
Expect rectifying column, laboratory small lot, high-purity, severe corrosive feed separation can only be carried out, and it is a large amount of useless to be difficult to industrialization
The recycling of acid.
The content of the invention
It is an object of the invention to provide a kind of method and device that sulfuric acid is reclaimed from nitrating wasting acid, have that cost is low, work
The characteristics of skill is simple, suitable industrialized production.
Involved nitrating wasting acid refers to waste liquid caused by nitration reaction in the present invention, the sulfuric acid containing high concentration and
Substantial amounts of aromatic compound, waste liquid, chloro- 2, the 4- dinitroanilines of 6- as caused by p acetamidoanisol and mixed acid nitrification
Caused waste liquid etc. in production.
The method provided by the present invention that sulfuric acid is reclaimed from nitrating wasting acid, comprises the following steps：
Nitrating wasting acid adsorbs through polymeric adsorbent successively, decolourize and UF membrane obtains acid-bearing wastewater；The acid-bearing wastewater is successively
Steam step-by-step heating is carried out into 1st effective evaporator A, 2nd effect evaporator, triple effect evaporator and four-effect evaporator, that is, is realized from institute
State the purpose that sulfuric acid is reclaimed in nitrating wasting acid.
In described method, the polymeric adsorbent can be anion exchange resin, as macroporous strong basic styrene series the moon from
Sub-exchange resin；Adsorption temp is normal temperature, and adsorption time is untill reaching adsorption saturation；
Most organic impurities can be removed by the adsorption step.
In described method, the decolorization process is carried out using activated carbon；
Using activated carbon conventional in the art, bleaching temperature is normal temperature, bleaching time be acid pickle color no longer
Untill obvious shoal occurs.
In described method, the UF membrane can use NF membrane, such as nanofiltration membrane；Separation temperature is normal temperature.
In described method, in a heated state, the part acid-bearing wastewater overflow in the 1st effective evaporator A to institute
State in 1st effective evaporator B, then sequentially enter in the 2nd effect evaporator, the triple effect evaporator and the four-effect evaporator.
In described method, what the 1st effective evaporator A, the 1st effective evaporator B and the 2nd effect evaporator evaporated
Water vapour contains a small amount of acid and organic matter, and condensed recovery is as nitrification wash water (i.e. nitration product slurry).
In described method, the water vapour that the triple effect evaporator and the four-effect evaporator evaporate is condensed into cold
Condensate storage pool, as washing water circulation use.
In described method, control the condition of the 1st effective evaporator A as follows：
It can be 88~130 DEG C to heat room temperature, and concretely 100 DEG C, evaporation chamber pressure can be 25~38kPa, specifically may be used
For 35kPa；
In described method, control the condition of the 2nd effect evaporator as follows：
It can be 116~136 DEG C to heat room temperature, and concretely 120 DEG C, evaporation chamber pressure can be 16~28kPa, specifically may be used
For 25kPa；
For acid-bearing wastewater after 2nd effect evaporator processing, sulfuric acid concentration reaches 65~78%, and such as 70%；
Control the condition of the triple effect evaporator as follows：
It can be 145~163 DEG C to heat room temperature, and concretely 150 DEG C, evaporation chamber pressure can be 9~18kPa, specifically may be used
For 15kPa；
After triple effect evaporator processing, sulfuric acid concentration reaches 75~85%, and such as 83%.
Control the condition of the four-effect evaporator as follows：
It can be 170~212 DEG C to heat room temperature, and concretely 190 DEG C, evaporation chamber pressure can be 3~12kPa, specifically may be used
For 10kPa；
After four-effect evaporator processing, sulfuric acid concentration reaches 90~99%, and such as 97%.
In described method, control the condition of the 1st effective evaporator B as follows：
Heating chamber treatment temperature can be 88~130 DEG C, concretely 110 DEG C, evaporation chamber pressure can be 25~
38kPa, concretely 35kPa；
Acid-bearing wastewater is after 1st effective evaporator A/ 1st effective evaporators B processing, and sulfuric acid concentration reaches 47~68%, such as
47%.
Can be as follows using the recovery of following device realization sulfuric acid from nitrating wasting acid, the structure of the device：
Including the polymeric adsorbent adsorption tower, activated carbon decolorizing tower and UF membrane tower being sequentially connected；
The liquid outlet of the UF membrane tower steams with 1st effective evaporator A, 2nd effect evaporator, triple effect evaporator and quadruple effect successively
Hair device is connected；
The liquid outlet of the 1st effective evaporator A is also connected with 1st effective evaporator B；
The 1st effective evaporator A, the 1st effective evaporator B, the 2nd effect evaporator, the triple effect evaporator and described four
The evaporation vapor outlet of effect evaporator is connected with condenser, for the water vapour condensation for evaporating four-effect evaporator；
Enter solid waste retracting device through the isolated solid waste of the UF membrane tower；
Described device is additionally included in the vacuum compressor that nitrating wasting acid is conveyed under negative pressure.
The present invention has the advantages that：
The present invention realizes the processing of nitrating wasting acid and the comprehensive utilization of resource, nitrating wasting acid adsorbed through polymeric adsorbent, after
Activated carbon decolorizing, micro-filtration UF membrane；Then after acid-bearing wastewater is heated, 1st effective evaporator A/ 1st effective evaporators B, two are sequentially entered
Evaporator, triple effect evaporator and four-effect evaporator are imitated, is heated by steam step-by-step, constantly evaporates moisture and organic impurities, is improved
The concentration and purity of sulfuric acid, finally give the sulfuric acid of high-purity, high concentration.It is difficult that the inventive method solves industrialization nitrating wasting acid
To reclaim high-concentration sulfuric acid, make its cycling and reutilization, and in generally use and/or produce the problems of other byproducts.Present invention side
The technological process of method is simple, and cost is low, and product purity is high, can directly obtain the sulfuric acid that concentration is more than 96%, the recovery of sulfuric acid
Rate is up to more than 97%, and the sulfuric acid of recovery is available for nitrification production technology to reuse, and resource can both be circulated, efficiently utilized, again
Can environmental protection.
Brief description of the drawings
Fig. 1 is the process chart of sulfuric acid in present invention recovery nitrating wasting acid.
Embodiment
Experimental method used in following embodiments is conventional method unless otherwise specified.
Material used, reagent etc., unless otherwise specified, are commercially obtained in following embodiments.
The present embodiment using the nitrating wasting acid in the production of Ningxia Ming Shengranhua Co., Ltds 6- chloro- 2,4- dinitroanilines as
Raw material.
According to the sulfuric acid in the flow recovery nitrating wasting acid shown in Fig. 1.
By nitrating wasting acid after settling tank settles, it is directly entered polymeric adsorbent adsorption tower and adsorbed under normal temperature, wherein inhaling
Attached resin is D201 macroporous strong basic styrene series anion exchange resin, and the spent acid after absorption enters activated carbon decolorizing tower,
Decolourized under normal temperature after reaching balance, into nanofiltration membrane knockout tower, normal temperature is separated off solid waste, and acid pickle is heated
Into 1st effective evaporator A, 1st effective evaporator A heating chambers are kept for 100 DEG C, and evaporation chamber pressure keeps 35kPa or so, 1st effective evaporator
Spent acid in A is partly overflowed in 1st effective evaporator B in a heated state, and 1st effective evaporator B heating chambers are kept for 110 DEG C, evaporation
Chamber pressure keeps 35kPa or so.Acid-bearing wastewater is after 1st effective evaporator A/B processing, into 2nd effect evaporator, 2nd effect evaporator
Heating room temperature is maintained at 120 DEG C, and evaporation chamber pressure keeps 25kPa, and acid-bearing wastewater is after 2nd effect evaporator is handled, into triple effect
Evaporator, the heating room temperature of triple effect evaporator are maintained at 150 DEG C, and evaporation chamber pressure keeps 15kPa, and acid-bearing wastewater steams through triple effect
After sending out device processing, into four-effect evaporator, the heating room temperature of four-effect evaporator is maintained at 190 DEG C, and evaporation chamber pressure is maintained at
10kPa, for acid-bearing wastewater after four-effect evaporator is handled, sulfuric acid concentration reaches 97%.
During above-mentioned recycling, after 1st effective evaporator A/ 1st effective evaporators B processing, sulfuric acid concentration reaches 47%；
After 2nd effect evaporator is handled, sulfuric acid concentration reaches 70%；After triple effect evaporator is handled, sulfuric acid concentration reaches 83%.
During above-mentioned recycling, water vapour that 1st effective evaporator A/ 1st effective evaporators B and 2nd effect evaporator evaporate,
Containing a small amount of acid and organic matter, condensed recovery is as nitrification wash water.
During above-mentioned recycling, water vapour that triple effect evaporator and four-effect evaporator evaporate, it is condensed enter it is cold
Condensate storage pool, as industrial washing water.
Claims (10)
1. a kind of method that sulfuric acid is reclaimed from nitrating wasting acid, comprises the following steps：
Nitrating wasting acid adsorbs through polymeric adsorbent successively, decolourize and UF membrane obtains acid-bearing wastewater；The acid-bearing wastewater sequentially enters
1st effective evaporator A, 2nd effect evaporator, triple effect evaporator and four-effect evaporator carry out steam step-by-step heating, that is, realize from the nitre
Change the purpose that sulfuric acid is reclaimed in spent acid.
2. according to the method for claim 1, it is characterised in that：The polymeric adsorbent is ion exchange resin.
3. method according to claim 1 or 2, it is characterised in that：The decolorization process is carried out using activated carbon；The film
Separation uses NF membrane.
4. according to the method any one of claim 1-3, it is characterised in that：Part institute in the 1st effective evaporator A
Acid-bearing wastewater overflow is stated into the 1st effective evaporator B, then sequentially enter the 2nd effect evaporator, the triple effect evaporator and
In the four-effect evaporator.
5. according to the method for claim 4, it is characterised in that：The 1st effective evaporator A, the 1st effective evaporator B and institute
State the condensed recovery of water vapour that 2nd effect evaporator evaporates and be used as nitrification wash water.
6. according to the method any one of claim 1-5, it is characterised in that：The triple effect evaporator and the quadruple effect steam
The water vapour that hair device evaporates is condensed into water condensate storage pond, as washing water circulation use.
7. according to the method any one of claim 1-6, it is characterised in that：Control the condition of the 1st effective evaporator A
It is as follows：
It is 88~130 DEG C to heat room temperature, and evaporation chamber pressure is 25~38kPa.
8. according to the method any one of claim 1-7, it is characterised in that：Control the condition of the 2nd effect evaporator such as
Under：
It is 116~136 DEG C to heat room temperature, and evaporation chamber pressure is 16~28kPa；
Control the condition of the triple effect evaporator as follows：
It is 145~163 DEG C to heat room temperature, and evaporation chamber pressure is 9~18kPa；
Control the condition of the four-effect evaporator as follows：
It is 170~212 DEG C to heat room temperature, and evaporation chamber pressure is 3~12kPa.
9. according to the method any one of claim 4-8, it is characterised in that：Control the condition of the 1st effective evaporator B
It is as follows：
Heating chamber treatment temperature is 88~130 DEG C, and evaporation chamber pressure is 25~38kPa.
10. a kind of device that sulfuric acid is reclaimed from nitrating wasting acid, including polymeric adsorbent adsorption tower, the activated carbon decolorizing being sequentially connected
Tower and UF membrane tower；
The liquid outlet of the UF membrane tower successively with 1st effective evaporator A, 2nd effect evaporator, triple effect evaporator and four-effect evaporator
It is connected；
The liquid outlet of the 1st effective evaporator A is also connected with 1st effective evaporator B；
The 1st effective evaporator A, the 1st effective evaporator B, the 2nd effect evaporator, the triple effect evaporator and the quadruple effect steam
The evaporation vapor outlet of hair device is connected with condenser.
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| CN201711078832.5A CN107814362A (en) | 2017-11-06 | 2017-11-06 | A kind of method and device that sulfuric acid is reclaimed from nitrating wasting acid |
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| CN201711078832.5A CN107814362A (en) | 2017-11-06 | 2017-11-06 | A kind of method and device that sulfuric acid is reclaimed from nitrating wasting acid |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110204125A (en) * | 2019-06-14 | 2019-09-06 | 齐鲁工业大学 | A kind of recycling reuse method of dangerization spent acid |
| CN111268843A (en) * | 2020-02-28 | 2020-06-12 | 河北大鹏医药化工有限公司 | Process for recovering nitric acid from nitrified wastewater |
| CN111392697A (en) * | 2020-03-18 | 2020-07-10 | 湖南吴赣药业有限公司 | Method for treating organic waste acid in synthesis of p-acetamido-benzenesulfonyl chloride |
| CN114163152A (en) * | 2021-11-24 | 2022-03-11 | 江苏宝众宝达药业股份有限公司 | Method for preparing building gypsum by recycling waste nitrified sulfuric acid |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110204125A (en) * | 2019-06-14 | 2019-09-06 | 齐鲁工业大学 | A kind of recycling reuse method of dangerization spent acid |
| CN110204125B (en) * | 2019-06-14 | 2022-04-01 | 齐鲁工业大学 | Resource recycling method for hazardous waste acid |
| CN111268843A (en) * | 2020-02-28 | 2020-06-12 | 河北大鹏医药化工有限公司 | Process for recovering nitric acid from nitrified wastewater |
| CN111268843B (en) * | 2020-02-28 | 2022-04-22 | 河北大鹏医药化工有限公司 | Process for recovering nitric acid from nitrified wastewater |
| CN111392697A (en) * | 2020-03-18 | 2020-07-10 | 湖南吴赣药业有限公司 | Method for treating organic waste acid in synthesis of p-acetamido-benzenesulfonyl chloride |
| CN111392697B (en) * | 2020-03-18 | 2021-10-26 | 湖南吴赣药业有限公司 | Method for treating organic waste acid in synthesis of p-acetamido-benzenesulfonyl chloride |
| CN114163152A (en) * | 2021-11-24 | 2022-03-11 | 江苏宝众宝达药业股份有限公司 | Method for preparing building gypsum by recycling waste nitrified sulfuric acid |
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