CN113582850A - Method for purifying 2, 4-dinitrochlorobenzene - Google Patents
Method for purifying 2, 4-dinitrochlorobenzene Download PDFInfo
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- CN113582850A CN113582850A CN202010368167.9A CN202010368167A CN113582850A CN 113582850 A CN113582850 A CN 113582850A CN 202010368167 A CN202010368167 A CN 202010368167A CN 113582850 A CN113582850 A CN 113582850A
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- dinitrochlorobenzene
- mixed
- heating
- mother liquor
- sweating
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- 238000000034 method Methods 0.000 title claims abstract description 45
- VYZAHLCBVHPDDF-UHFFFAOYSA-N Dinitrochlorobenzene Chemical compound [O-][N+](=O)C1=CC=C(Cl)C([N+]([O-])=O)=C1 VYZAHLCBVHPDDF-UHFFFAOYSA-N 0.000 title claims abstract description 39
- 238000010438 heat treatment Methods 0.000 claims abstract description 44
- 239000012452 mother liquor Substances 0.000 claims abstract description 37
- 230000035900 sweating Effects 0.000 claims abstract description 31
- 238000001816 cooling Methods 0.000 claims abstract description 24
- BPPMIQPXQVIZNJ-UHFFFAOYSA-N 2-chloro-1,3-dinitrobenzene Chemical compound [O-][N+](=O)C1=CC=CC([N+]([O-])=O)=C1Cl BPPMIQPXQVIZNJ-UHFFFAOYSA-N 0.000 claims abstract description 17
- 239000013078 crystal Substances 0.000 claims abstract description 17
- 210000004243 sweat Anatomy 0.000 claims abstract description 8
- 238000000926 separation method Methods 0.000 abstract description 7
- 239000002904 solvent Substances 0.000 abstract description 6
- 238000000746 purification Methods 0.000 abstract description 5
- 238000002425 crystallisation Methods 0.000 abstract description 4
- 238000005265 energy consumption Methods 0.000 abstract description 4
- 238000011084 recovery Methods 0.000 abstract description 3
- 239000002994 raw material Substances 0.000 description 5
- MVPPADPHJFYWMZ-UHFFFAOYSA-N chlorobenzene Chemical compound ClC1=CC=CC=C1 MVPPADPHJFYWMZ-UHFFFAOYSA-N 0.000 description 4
- PGYZAKRTYUHXRA-UHFFFAOYSA-N 2,10-dinitro-12h-[1,4]benzothiazino[3,2-b]phenothiazin-3-one Chemical compound S1C2=CC(=O)C([N+]([O-])=O)=CC2=NC2=C1C=C1SC3=CC=C([N+](=O)[O-])C=C3NC1=C2 PGYZAKRTYUHXRA-UHFFFAOYSA-N 0.000 description 3
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 3
- BFCFYVKQTRLZHA-UHFFFAOYSA-N 1-chloro-2-nitrobenzene Chemical compound [O-][N+](=O)C1=CC=CC=C1Cl BFCFYVKQTRLZHA-UHFFFAOYSA-N 0.000 description 2
- CZGCEKJOLUNIFY-UHFFFAOYSA-N 4-Chloronitrobenzene Chemical compound [O-][N+](=O)C1=CC=C(Cl)C=C1 CZGCEKJOLUNIFY-UHFFFAOYSA-N 0.000 description 2
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 2
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 2
- 238000009835 boiling Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- WZCQRUWWHSTZEM-UHFFFAOYSA-N 1,3-phenylenediamine Chemical compound NC1=CC=CC(N)=C1 WZCQRUWWHSTZEM-UHFFFAOYSA-N 0.000 description 1
- UFBJCMHMOXMLKC-UHFFFAOYSA-N 2,4-dinitrophenol Chemical compound OC1=CC=C([N+]([O-])=O)C=C1[N+]([O-])=O UFBJCMHMOXMLKC-UHFFFAOYSA-N 0.000 description 1
- 244000144725 Amygdalus communis Species 0.000 description 1
- 235000003893 Prunus dulcis var amara Nutrition 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- -1 chlorobenzene method Chemical compound 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 239000000975 dye Substances 0.000 description 1
- 229940018564 m-phenylenediamine Drugs 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- LZGUHMNOBNWABZ-UHFFFAOYSA-N n-nitro-n-phenylnitramide Chemical compound [O-][N+](=O)N([N+]([O-])=O)C1=CC=CC=C1 LZGUHMNOBNWABZ-UHFFFAOYSA-N 0.000 description 1
- 238000006396 nitration reaction Methods 0.000 description 1
- 125000000449 nitro group Chemical group [O-][N+](*)=O 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 239000000575 pesticide Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C201/00—Preparation of esters of nitric or nitrous acid or of compounds containing nitro or nitroso groups bound to a carbon skeleton
- C07C201/06—Preparation of nitro compounds
- C07C201/16—Separation; Purification; Stabilisation; Use of additives
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention relates to a method for purifying 2, 4-dinitrochlorobenzene, which comprises the following steps: s1, conveying the mixed mother liquor of 2, 4-dinitrochlorobenzene and 2, 6-dinitrochlorobenzene to a crystallizer, and cooling to 15 +/-1 ℃; step S2: step S1, gradually heating the cooled mixed mother liquor to make the crystal sweat; step S21, collecting mixed low oil in the process of heating and sweating, wherein the mixed low oil contains 2.6-dinitrochlorobenzene with the volume fraction of 30 +/-1%; step S22: collecting mixed high oil, wherein the mixed high oil contains 2.6-dinitrochlorobenzene with the volume fraction of 10 +/-1%; step S23: finally obtaining the 2.4-dinitrochlorobenzene crystal with the purity of more than 99.5 percent. The purification method disclosed by the invention is low in energy consumption and temperature, has no three wastes, is the cleanest separation method at present, avoids the risk of high-temperature separation, and also avoids the solvent recovery of a solvent crystallization method.
Description
Technical Field
The invention relates to a purification method of 2, 4-dinitrochlorobenzene, belonging to the technical field of purification methods of chemical products.
Background
2, 4-dinitrochlorobenzene is a pale yellow or yellowish brown needle-like crystal with bitter almond taste, and its molecular formula is C6H3ClN2O4The molecular weight is 202.56, and the relative density is 1.69g/cm3The product has boiling point of 315 ℃, melting point of 53.4 ℃, flash point of 194 ℃, is insoluble in water, is soluble in organic solvents such as ether, benzene, ethanol and the like, is mainly used as raw materials of dyes, pesticides, medicines and the like, and can be used for producing sulfur black, dinitrophenol, dinitroaniline and m-phenylenediamine.
Three methods are available for producing 2, 4-dinitrochlorobenzene, namely chlorobenzene method, p-nitrochlorobenzene method and o-nitrochlorobenzene method. The chlorobenzene method has higher cost, and the purity of products produced by the p-nitrochlorobenzene method and the o-nitrochlorobenzene method cannot meet the requirement, because the isomers of the nitro mixture generated by the nitration reaction of mixed acid have very close chemical properties, especially close boiling points. Therefore, the invention aims to solve the technical problem by providing a pure physical and high-safety method for purifying 2, 4-dinitrochlorobenzene.
Disclosure of Invention
The invention aims to solve the defects of the prior art and provides a method for purifying 2, 4-dinitrochlorobenzene. The method is based on the mixed mother liquor of 2, 4-dinitrochlorobenzene and 2, 6-dinitrochlorobenzene, adopts a physical separation method, and has the advantages of low energy consumption, no pollution, high product quality, safety and reliability.
The technical scheme adopted by the invention for solving the technical problems is as follows:
a method of purifying 2, 4-dinitrochlorobenzene, the method comprising the steps of:
s1, conveying the mixed mother liquor of 2, 4-dinitrochlorobenzene and 2, 6-dinitrochlorobenzene to a crystallizer, and cooling to 15 +/-1 ℃;
step S2: step S1, gradually heating the cooled mixed mother liquor to make the crystal sweat;
step S21, collecting mixed low oil in the process of heating and sweating, wherein the mixed low oil contains 2.6-dinitrochlorobenzene with the volume fraction of 30 +/-1%;
step S22: collecting mixed high oil, wherein the mixed high oil contains 2.6-dinitrochlorobenzene with the volume fraction of 10 +/-1%;
step S23: finally obtaining the 2.4-dinitrochlorobenzene crystal with the purity of more than 99.5 percent.
Preferably, in step S1, the mixed mother liquor contains 89 to 93% of 2, 4-dinitrochlorobenzene, 7 to 11% of 2, 6-dinitrochlorobenzene, and the total content of the two is 100%.
Preferably, in step S1, the mixed mother liquor contains 90% of 2, 4-dinitrochlorobenzene and 10% of 2, 6-dinitrochlorobenzene.
Preferably, in step S1, the cooling rate of the mixed mother liquor in the crystallizer is 0.1-0.2 ℃/min, and the final temperature of cooling is controlled to be 15 ± 0.5 ℃.
More preferably, in step S1, the cooling rate of the mixed mother liquor in the crystallizer is 0.15 ℃/min.
Preferably, in step S2, the temperature-rising rate of temperature-rising sweating is 0.05-0.08 ℃/min, the final temperature of temperature-rising sweating is controlled at 50-64 ℃, and the total time of temperature-rising sweating is controlled at 10-12 hours.
More preferably, the heating rate for heating and sweating is 0.06 ℃/min.
The invention has the beneficial effects that: the purification method disclosed by the invention is low in energy consumption and temperature, has no three wastes, is the cleanest separation method at present, avoids the risk of high-temperature separation, and also avoids the solvent recovery of a solvent crystallization method. In addition, the mixed high oil can be further purified and separated according to the steps of the invention repeatedly to obtain the 2, 4-dinitrochlorobenzene, and the mixed low oil can be directly used as a raw material for producing the sulfur black, so that the comprehensive utilization efficiency of the material is improved, and the additional value of the mixed mother liquor of the 2, 4-dinitrochlorobenzene and the 2, 6-dinitrochlorobenzene is improved.
Detailed Description
The technical solution of the present invention will be further specifically described below by way of specific examples.
In examples 1 to 5 of the present invention, all the crystallizers used were commercially available conventional crystallizers, and each of the raw materials was a commercially available conventional raw material.
Example 1:
a method of purifying 2, 4-dinitrochlorobenzene, the method comprising the steps of:
s1, conveying the mixed mother liquor of the 2, 4-dinitrochlorobenzene and the 2, 6-dinitrochlorobenzene to a crystallizer, and cooling to 14 ℃;
step S2: step S1, gradually heating the cooled mixed mother liquor to make the crystal sweat;
step S21, collecting mixed low oil in the process of heating and sweating, wherein the mixed low oil contains 29% volume fraction of 2.6-dinitrochlorobenzene;
step S22: collecting mixed high oil, wherein the mixed high oil contains 9% of 2.6-dinitrochlorobenzene by volume fraction;
step S23: finally obtaining the 2.4-dinitrochlorobenzene crystal with the purity of more than 99.5 percent.
Specifically, in step S1, the content of 2.4-dinitrochlorobenzene in the mixed mother liquor is 89%, the content of 2.6-dinitrochlorobenzene is 11%, and the sum of the contents is 100%, in step S1, the cooling rate of the mixed mother liquor in a crystallizer is 0.1 ℃/min, the final temperature of cooling is controlled at 14 ℃, in step S2, the heating rate of heating and sweating is 0.05 ℃/min, the final temperature of heating and sweating is controlled at 50 ℃, and the total time of heating and sweating is controlled at 12 hours.
Example 2:
a method of purifying 2, 4-dinitrochlorobenzene, the method comprising the steps of:
s1, conveying the mixed mother liquor of the 2, 4-dinitrochlorobenzene and the 2, 6-dinitrochlorobenzene to a crystallizer, and cooling to 16 ℃;
step S2: step S1, gradually heating the cooled mixed mother liquor to make the crystal sweat;
step S21, collecting mixed low oil in the process of heating and sweating, wherein the mixed low oil contains 31% volume fraction of 2.6-dinitrochlorobenzene;
step S22: collecting mixed high oil, wherein the mixed high oil contains 11% of 2, 6-dinitrochlorobenzene by volume fraction;
step S23: finally obtaining the 2.4-dinitrochlorobenzene crystal with the purity of more than 99.5 percent.
Specifically, in step S1, the content of 2.4-dinitrochlorobenzene in the mixed mother liquor is 93%, the content of 2.6-dinitrochlorobenzene is 7%, and the sum of the contents is 100%, in step S1, the cooling rate of the mixed mother liquor in a crystallizer is 0.2 ℃/min, the final temperature of cooling is controlled at 16 ℃, in step S2, the heating rate of heating and sweating is 0.08 ℃/min, the final temperature of heating and sweating is controlled at 64 ℃, and the total time of heating and sweating is controlled at 10 hours.
Example 3:
a method of purifying 2, 4-dinitrochlorobenzene, the method comprising the steps of:
s1, conveying the mixed mother liquor of the 2, 4-dinitrochlorobenzene and the 2, 6-dinitrochlorobenzene to a crystallizer, and cooling to 15 ℃;
step S2: step S1, gradually heating the cooled mixed mother liquor to make the crystal sweat;
step S21, collecting mixed low oil in the process of heating and sweating, wherein the mixed low oil contains 2.6-dinitrochlorobenzene with the volume fraction of 30%;
step S22: collecting mixed high oil, wherein the mixed high oil contains 10% of 2.6-dinitrochlorobenzene by volume fraction;
step S23: finally obtaining the 2.4-dinitrochlorobenzene crystal with the purity of more than 99.5 percent.
Specifically, in step S1, the content of 2.4-dinitrochlorobenzene in the mixed mother liquor is 90%, the content of 2.6-dinitrochlorobenzene is 10%, in step S1, the cooling rate of the mixed mother liquor in a crystallizer is 0.15 ℃/min, the final temperature of cooling is controlled at 15 ℃, in step S2, the heating rate of heating and sweating is 0.06 ℃/min, the final temperature of heating and sweating is controlled at 51 ℃, and the total time of heating and sweating is controlled at 10 hours.
Example 4:
a method of purifying 2, 4-dinitrochlorobenzene, the method comprising the steps of:
s1, conveying the mixed mother liquor of the 2, 4-dinitrochlorobenzene and the 2, 6-dinitrochlorobenzene to a crystallizer, and cooling to 16 ℃;
step S2: step S1, gradually heating the cooled mixed mother liquor to make the crystal sweat;
step S21, collecting mixed low oil in the process of heating and sweating, wherein the mixed low oil contains 31% volume fraction of 2.6-dinitrochlorobenzene;
step S22: collecting mixed high oil, wherein the mixed high oil contains 11% of 2, 6-dinitrochlorobenzene by volume fraction;
step S23: finally obtaining the 2.4-dinitrochlorobenzene crystal with the purity of more than 99.5 percent.
Specifically, in step S1, the content of 2.4-dinitrochlorobenzene in the mixed mother liquor is 92%, the content of 2.6-dinitrochlorobenzene is 8%, and the sum of the contents is 100%, in step S1, the cooling rate of the mixed mother liquor in a crystallizer is 0.2 ℃/min, the final temperature of cooling is controlled at 16 ℃, in step S2, the heating rate of heating and sweating is 0.06 ℃/min, the final temperature of heating and sweating is controlled at 59.2 ℃, and the total time of heating and sweating is controlled at 12 hours.
Example 5:
a method of purifying 2, 4-dinitrochlorobenzene, the method comprising the steps of:
s1, conveying the mixed mother liquor of the 2, 4-dinitrochlorobenzene and the 2, 6-dinitrochlorobenzene to a crystallizer, and cooling to 15 ℃;
step S2: step S1, gradually heating the cooled mixed mother liquor to make the crystal sweat;
step S21, collecting mixed low oil in the process of heating and sweating, wherein the mixed low oil contains 2.6-dinitrochlorobenzene with the volume fraction of 30%;
step S22: collecting mixed high oil, wherein the mixed high oil contains 10% of 2.6-dinitrochlorobenzene by volume fraction;
step S23: finally obtaining the 2.4-dinitrochlorobenzene crystal with the purity of more than 99.5 percent.
Preferably, in step S1, the content of 2.4-dinitrochlorobenzene in the mixed mother liquor is 91%, the content of 2.6-dinitrochlorobenzene is 9%, and the sum of the contents is 100%, in step S1, the cooling rate of the mixed mother liquor in the crystallizer is 0.18 ℃/min, the final cooling temperature is controlled at 15 ℃, in step S2, the heating rate of heating and sweating is 0.07 ℃/min, the final heating and sweating temperature is controlled at 57 ℃, and the total heating and sweating time is controlled at 10 hours.
In examples 1 to 5, the purity and the crystallization yield of purified 2, 4-dinitrochlorobenzene were as follows:
the purification method disclosed by the invention is low in energy consumption and temperature, has no three wastes, is the cleanest separation method at present, avoids the risk of high-temperature separation, and also avoids the solvent recovery of a solvent crystallization method. In addition, the mixed high oil can be further purified and separated according to the steps of the invention repeatedly to obtain the 2, 4-dinitrochlorobenzene, and the mixed low oil can be directly used as a raw material for producing the sulfur black, so that the comprehensive utilization efficiency of the material is improved, and the additional value of the mixed mother liquor of the 2, 4-dinitrochlorobenzene and the 2, 6-dinitrochlorobenzene is improved.
The above-described embodiments are only preferred embodiments of the present invention, and are not intended to limit the present invention in any way, and other variations and modifications may be made without departing from the spirit of the invention as set forth in the claims.
Claims (7)
1. A method for purifying 2, 4-dinitrochlorobenzene, which is characterized by comprising the following steps:
s1, conveying the mixed mother liquor of 2, 4-dinitrochlorobenzene and 2, 6-dinitrochlorobenzene to a crystallizer, and cooling to 15 +/-1 ℃;
step S2: step S1, gradually heating the cooled mixed mother liquor to make the crystal sweat;
step S21, collecting mixed low oil in the process of heating and sweating, wherein the mixed low oil contains 2.6-dinitrochlorobenzene with the volume fraction of 30 +/-1%;
step S22: collecting mixed high oil, wherein the mixed high oil contains 2.6-dinitrochlorobenzene with the volume fraction of 10 +/-1%;
step S23: finally obtaining the 2.4-dinitrochlorobenzene crystal with the purity of more than 99.5 percent.
2. The method of purifying 2, 4-dinitrochlorobenzene according to claim 1, wherein in step S1, the mixed mother liquor contains 89 to 93% of 2, 4-dinitrochlorobenzene, 7 to 11% of 2, 6-dinitrochlorobenzene, and the sum of the contents is 100%.
3. The method of purifying 2, 4-dinitrochlorobenzene according to claim 2, wherein in step S1, the mixed mother liquor contains 90% of 2, 4-dinitrochlorobenzene and 10% of 2, 6-dinitrochlorobenzene.
4. The method for purifying 2, 4-dinitrochlorobenzene according to claim 1, wherein in step S1, the cooling rate of the mixed mother liquor in the crystallizer is 0.1-0.2 ℃/min, and the final temperature of the cooling is controlled to be 15 ± 0.5 ℃.
5. The method for purifying 2, 4-dinitrochlorobenzene according to claim 4, wherein in step S1, the cooling rate of the mixed mother liquor in the crystallizer is 0.15 ℃/min.
6. The method for purifying 2, 4-dinitrochlorobenzene according to claim 1, wherein in step S2, the heating rate for heating and sweating is 0.05-0.08 ℃/min, the final temperature for heating and sweating is controlled to be 50-64 ℃, and the total time for heating and sweating is controlled to be 10-12 hours.
7. The method for purifying 2, 4-dinitrochlorobenzene according to claim 6, wherein the heating rate for heating and sweating is 0.06 ℃/min.
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| CN202010368167.9A CN113582850A (en) | 2020-04-30 | 2020-04-30 | Method for purifying 2, 4-dinitrochlorobenzene |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115160141A (en) * | 2021-04-01 | 2022-10-11 | 浙江省常山长盛化工有限公司 | Method for producing 2,4-dinitrochlorobenzene by one-step nitration of chlorobenzene |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5395995A (en) * | 1992-05-18 | 1995-03-07 | Bayer Aktiengesellschaft | Process for the preparation and purification of nitroaromatics |
-
2020
- 2020-04-30 CN CN202010368167.9A patent/CN113582850A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5395995A (en) * | 1992-05-18 | 1995-03-07 | Bayer Aktiengesellschaft | Process for the preparation and purification of nitroaromatics |
Non-Patent Citations (1)
| Title |
|---|
| 熊道陵 等: "《洗油分离精制应用技术》", 冶金工业出版社, pages: 222 - 224 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115160141A (en) * | 2021-04-01 | 2022-10-11 | 浙江省常山长盛化工有限公司 | Method for producing 2,4-dinitrochlorobenzene by one-step nitration of chlorobenzene |
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Application publication date: 20211102 |