Production process of p-nitrochlorobenzene

Abstract

The invention relates to the technical field of chemical raw materials, and discloses a production process of p-nitrochlorobenzene, which comprises the following steps: carrying out nitration reaction on chlorobenzene and nitric acid as raw materials under the catalytic action of a catalyst to generate a mixture containing p-nitrochlorobenzene and o-nitrochlorobenzene, and carrying out post-treatment on the mixture of p-nitrochlorobenzene and o-nitrochlorobenzene to obtain p-nitrochlorobenzene. A p-nitrochlorobenzene product is obtained; according to the method, the chlorobenzene and the nitric acid are used as raw materials to be subjected to nitration reaction under the catalytic action of the catalyst, the p-nitrochlorobenzene product is obtained, energy consumption is low, pollution is avoided, and the obtained p-nitrochlorobenzene product is high in quality, purity and yield.

Description

Technical Field

[0001] The invention relates to the technical field of chemical raw materials, in particular to a production process of p-nitrochlorobenzene. Background Art

[0002] 4-Nitrochlorobenzene, also known as p-nitrochlorobenzene, is an organic compound with the chemical formula C6H4ClNO2. It is a light yellow crystalline powder, insoluble in water, slightly soluble in ethanol, ether, and carbon disulfide, and is mainly used as a dye intermediate.

[0003] Prior art: Application publication number CN103086892A specifically discloses "The present invention relates to a method for preparing p-nitrochlorobenzene by nitrating chlorobenzene with nitrogen dioxide, using chlorobenzene as a raw material and nitrogen dioxide as a nitrating reagent to prepare p-nitrochlorobenzene. The present invention improves the utilization rate of reaction atoms, increases the environmental economy of industrial preparation reactions, and reduces environmental pollution. At the same time, the present invention provides a method for nitrating acid-sensitive compounds, which can be used for the nitration of many aromatic compounds, and can even nitrate aromatic compounds containing multiple passivating groups." Because, in the prior art, nitrogen dioxide is used as a nitrating reagent, its nitrating performance is relatively general, and the reaction sufficiency is relatively low, resulting in relatively low purity and yield of p-nitrochlorobenzene obtained by the preparation process of p-nitrochlorobenzene.

[0004] Based on this, the present invention provides a production process of p-nitrochlorobenzene to solve the corresponding problem. Summary of the invention

[0005] In view of the problems in the prior art, the present invention provides a production process of p-nitrochlorobenzene.

[0006] The technical solution adopted by the present invention to solve the technical problem is: a production process of p-nitrochlorobenzene, comprising: using chlorobenzene and nitric acid as raw materials to carry out nitration reaction under the catalytic action of a catalyst to generate a mixture containing p-nitrochlorobenzene and o-nitrochlorobenzene, and then post-treating the mixture of p-nitrochlorobenzene and o-nitrochlorobenzene to obtain a p-nitrochlorobenzene product;

[0007] The reaction temperature is 125-130°C, the reaction time is 1.5-2 hours, the reaction pressure is 0.6MPa in the initial 30 minutes, and the pressure is 0.3-0.4MPa after 30 minutes.

[0008] As a further technical solution: the catalyst preparation method is:

[0009] First, bamboo powder is added to a sodium hydroxide solution and stirred for 40 minutes, then filtered, washed with water until neutral, and dried until the moisture content is less than 10% to obtain pretreated bamboo powder;

[0010] Among them, the mixing ratio of bamboo powder and sodium hydroxide solution is 30g:120mL;

[0011] The mass fraction of the sodium hydroxide solution is 3.5%;

[0012] The pretreated bamboo powder obtained above is subjected to steam explosion treatment, and then dried to a moisture content of less than 10%, and then carbonized under an inert atmosphere to obtain a carbide;

[0013] Among them, the steam explosion pressure is 3MPa, the temperature is 228℃, and the steam explosion time is 1 hour;

[0014] The inert atmosphere was nitrogen, the carbonization temperature was 420°C, and the time was 8 hours;

[0015] The carbide and concentrated sulfuric acid are mixed, heated to react for 2 hours, filtered, and dried to obtain;

[0016] The mass ratio of carbide and concentrated sulfuric acid is 1:2;

[0017] The mass fraction of concentrated sulfuric acid is 80% and the reaction temperature is 85°C.

[0018] As a further technical solution: the specific chemical equation of the nitration reaction is:

[0019]

[0020] As a further technical solution: the post-treatment includes: neutralization, water washing, dehydration, and crystallization;

[0021] Wherein, before post-treatment, the mixture containing p-nitrochlorobenzene and o-nitrochlorobenzene is separated into a nitrate oil phase and an acid phase, and the nitrate oil phase is post-treated.

[0022] As a further technical solution: the neutralization is:

[0023] Add the nitrate oil phase into the alkali washing pot for alkali washing;

[0024] Alkali washing adopts: sodium hydroxide solution is used to carry out alkaline washing treatment on the nitrate oil phase, and the sodium hydroxide solution and the nitrate oil phase are mixed and alkaline washed in a mass ratio of 2:1 to form a neutralization reaction, and then water-oil separation is performed to obtain alkaline nitrate oil;

[0025] Wherein, the concentration of sodium hydroxide solution is 5 mol / L.

[0026] As a further technical solution: water washing is:

[0027] The alkaline nitrate oil is mixed with water and washed with water. After the washing is completed, it is separated by a water washing separator to obtain neutral nitrate oil.

[0028] As a further technical solution: dehydration is:

[0029] The neutral nitrate oil is subjected to a dehydration and drying treatment to obtain dry nitrate oil.

[0030] As a further technical solution: crystallization is:

[0031] The dried nitric acid oil is subjected to distillation separation treatment to remove o-nitrochlorobenzene, and then cooled and crystallized to obtain p-nitrochlorobenzene.

[0032] Beneficial effects of the present invention:

[0033] The invention uses chlorobenzene and nitric acid as raw materials and performs nitration reaction under the catalytic action of a special catalyst to obtain a p-nitrochlorobenzene product, which has low energy consumption and no pollution. The obtained p-nitrochlorobenzene product has high quality, high purity and high yield. The special catalyst of the invention has higher catalytic efficiency and can reduce the generation of side reactions.

[0034] Through a large number of experimental studies, the present invention can greatly improve the purity and crystallization yield of the obtained chloronitrobenzene product by adjusting the reaction pressure in various ways. The present invention mainly adjusts the reaction pressure to a high pressure of 0.6MPa 30 minutes before the reaction, and starts to adjust and reduce the reaction pressure to 0.3-0.4MPa after 30 minutes, thereby improving the reaction process, achieving sufficient reaction, and reducing the generation of by-products, thereby laying a high foundation for improving the high purity and high crystallization yield of the chloronitrobenzene product. DETAILED DESCRIPTION

[0035] In order to enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work should fall within the scope of protection of the present application.

[0036] Example 1

[0037] A production process of p-nitrochlorobenzene, comprising: using chlorobenzene and nitric acid as raw materials to carry out a nitration reaction under the catalytic action of a catalyst to generate a mixture containing p-nitrochlorobenzene and o-nitrochlorobenzene, and then post-treating the mixture of p-nitrochlorobenzene and o-nitrochlorobenzene to obtain a p-nitrochlorobenzene product;

[0038] The reaction temperature was 125°C, the reaction time was 1.5 hours, the reaction pressure was 0.6 MPa in the initial 30 minutes, and the pressure was 0.3 MPa after 30 minutes.

[0039] Wherein chlorobenzene and nitric acid are fed in a molar ratio of 1:1.5;

[0040] The catalyst preparation method is:

[0041] First, bamboo powder is added to a sodium hydroxide solution and stirred for 40 minutes, then filtered, washed with water until neutral, and dried until the moisture content is less than 10% to obtain pretreated bamboo powder;

[0042] Among them, the mixing ratio of bamboo powder and sodium hydroxide solution is 30g:120mL;

[0043] The mass fraction of the sodium hydroxide solution is 3.5%;

[0044] The pretreated bamboo powder obtained above is subjected to steam explosion treatment, and then dried to a moisture content of less than 10%, and then carbonized under an inert atmosphere to obtain a carbide;

[0045] Among them, the steam explosion pressure is 3MPa, the temperature is 228℃, and the steam explosion time is 1 hour;

[0046] The inert atmosphere was nitrogen, the carbonization temperature was 420°C, and the time was 8 hours;

[0047] The carbide and concentrated sulfuric acid are mixed, heated to react for 2 hours, filtered, and dried to obtain;

[0048] The mass ratio of carbide and concentrated sulfuric acid is 1:2;

[0049] The mass fraction of concentrated sulfuric acid is 80%, the reaction temperature is 85°C, and the amount of catalyst added is 3% of the mass of chlorobenzene.

[0050] Post-treatment includes: neutralization, washing, dehydration, and crystallization;

[0051] Wherein, before post-treatment, the mixture containing p-nitrochlorobenzene and o-nitrochlorobenzene is separated into a nitrate oil phase and an acid phase, and the nitrate oil phase is post-treated.

[0052] Neutralization:

[0053] Add the nitrate oil phase into the alkali washing pot for alkali washing;

[0054] Alkali washing adopts: sodium hydroxide solution is used to carry out alkaline washing treatment on the nitrate oil phase, and the sodium hydroxide solution and the nitrate oil phase are mixed and alkaline washed in a mass ratio of 2:1 to form a neutralization reaction, and then water-oil separation is performed to obtain alkaline nitrate oil;

[0055] Wherein, the concentration of sodium hydroxide solution is 5 mol / L.

[0056] Washing:

[0057] The alkaline nitrate oil is mixed with water and washed with water. After the washing is completed, it is separated by a water washing separator to obtain neutral nitrate oil.

[0058] Dehydration for:

[0059] The neutral nitrate oil is subjected to a dehydration and drying treatment to obtain dry nitrate oil.

[0060] Crystallization is:

[0061] The dried nitric acid oil is subjected to distillation separation treatment to remove o-nitrochlorobenzene, and then cooled and crystallized to obtain p-nitrochlorobenzene.

[0062] Example 2

[0063] A production process of p-nitrochlorobenzene, comprising: using chlorobenzene and nitric acid as raw materials to carry out a nitration reaction under the catalytic action of a catalyst to generate a mixture containing p-nitrochlorobenzene and o-nitrochlorobenzene, and then post-treating the mixture of p-nitrochlorobenzene and o-nitrochlorobenzene to obtain a p-nitrochlorobenzene product;

[0064] The reaction temperature was 128°C, the reaction time was 2 hours, the reaction pressure was 0.6 MPa in the initial 30 minutes, and the pressure was 0.33 MPa after 30 minutes.

[0065] Wherein chlorobenzene and nitric acid are fed in a molar ratio of 1:1.5;

[0066] The catalyst preparation method is:

[0067] First, bamboo powder is added to a sodium hydroxide solution and stirred for 40 minutes, then filtered, washed with water until neutral, and dried until the moisture content is less than 10% to obtain pretreated bamboo powder;

[0068] Among them, the mixing ratio of bamboo powder and sodium hydroxide solution is 30g:120mL;

[0069] The mass fraction of the sodium hydroxide solution is 3.5%;

[0070] The pretreated bamboo powder obtained above is subjected to steam explosion treatment, and then dried to a moisture content of less than 10%, and then carbonized under an inert atmosphere to obtain a carbide;

[0071] Among them, the steam explosion pressure is 3MPa, the temperature is 228℃, and the steam explosion time is 1 hour;

[0072] The inert atmosphere was nitrogen, the carbonization temperature was 420°C, and the time was 8 hours;

[0073] The carbide and concentrated sulfuric acid are mixed, heated to react for 2 hours, filtered, and dried to obtain;

[0074] The mass ratio of carbide and concentrated sulfuric acid is 1:2;

[0075] The mass fraction of concentrated sulfuric acid is 80%, the reaction temperature is 85°C, and the amount of catalyst added is 3.4% of the mass of chlorobenzene.

[0076] Post-treatment includes: neutralization, washing, dehydration, and crystallization;

[0077] Wherein, before post-treatment, the mixture containing p-nitrochlorobenzene and o-nitrochlorobenzene is separated into a nitrate oil phase and an acid phase, and the nitrate oil phase is post-treated.

[0078] Neutralization:

[0079] Add the nitrate oil phase into the alkali washing pot for alkali washing;

[0080] Alkali washing adopts: sodium hydroxide solution is used to carry out alkaline washing treatment on the nitrate oil phase, and the sodium hydroxide solution and the nitrate oil phase are mixed and alkaline washed in a mass ratio of 2:1 to form a neutralization reaction, and then water-oil separation is performed to obtain alkaline nitrate oil;

[0081] Wherein, the concentration of sodium hydroxide solution is 5 mol / L.

[0082] Washing:

[0083] The alkaline nitrate oil is mixed with water and washed with water. After the washing is completed, it is separated by a water washing separator to obtain neutral nitrate oil.

[0084] Dehydration for:

[0085] The neutral nitrate oil is subjected to a dehydration and drying treatment to obtain dry nitrate oil.

[0086] Crystallization is:

[0087] The dried nitric acid oil is subjected to distillation separation treatment to remove o-nitrochlorobenzene, and then cooled and crystallized to obtain p-nitrochlorobenzene.

[0088] Example 3

[0089] A production process of p-nitrochlorobenzene, comprising: using chlorobenzene and nitric acid as raw materials to carry out a nitration reaction under the catalytic action of a catalyst to generate a mixture containing p-nitrochlorobenzene and o-nitrochlorobenzene, and then post-treating the mixture of p-nitrochlorobenzene and o-nitrochlorobenzene to obtain a p-nitrochlorobenzene product;

[0090] The reaction temperature was 129°C, the reaction time was 1.5 hours, the reaction pressure was 0.6 MPa in the initial 30 minutes, and the pressure was 0.38 MPa after 30 minutes.

[0091] Wherein chlorobenzene and nitric acid are fed in a molar ratio of 1:1.2;

[0092] The catalyst preparation method is:

[0093] First, bamboo powder is added to a sodium hydroxide solution and stirred for 40 minutes, then filtered, washed with water until neutral, and dried until the moisture content is less than 10% to obtain pretreated bamboo powder;

[0094] Among them, the mixing ratio of bamboo powder and sodium hydroxide solution is 30g:120mL;

[0095] The mass fraction of the sodium hydroxide solution is 3.5%;

[0096] The pretreated bamboo powder obtained above is subjected to steam explosion treatment, and then dried to a moisture content of less than 10%, and then carbonized under an inert atmosphere to obtain a carbide;

[0097] Among them, the steam explosion pressure is 3MPa, the temperature is 228℃, and the steam explosion time is 1 hour;

[0098] The inert atmosphere was nitrogen, the carbonization temperature was 420°C, and the time was 8 hours;

[0099] The carbide and concentrated sulfuric acid are mixed, heated to react for 2 hours, filtered, and dried to obtain;

[0100] The mass ratio of carbide and concentrated sulfuric acid is 1:2;

[0101] The mass fraction of concentrated sulfuric acid is 80%, the reaction temperature is 85°C, and the amount of catalyst added is 3.8% of the mass of chlorobenzene.

[0102] Post-treatment includes: neutralization, washing, dehydration, and crystallization;

[0103] Wherein, before post-treatment, the mixture containing p-nitrochlorobenzene and o-nitrochlorobenzene is separated into a nitrate oil phase and an acid phase, and the nitrate oil phase is post-treated.

[0104] Neutralization:

[0105] Add the nitrate oil phase into the alkali washing pot for alkali washing;

[0106] Alkali washing adopts: sodium hydroxide solution is used to carry out alkaline washing treatment on the nitrate oil phase, and the sodium hydroxide solution and the nitrate oil phase are mixed and alkaline washed in a mass ratio of 2:1 to form a neutralization reaction, and then water-oil separation is performed to obtain alkaline nitrate oil;

[0107] Wherein, the concentration of sodium hydroxide solution is 5 mol / L.

[0108] Washing:

[0109] The alkaline nitrate oil is mixed with water and washed with water. After the washing is completed, it is separated by a water washing separator to obtain neutral nitrate oil.

[0110] Dehydration for:

[0111] The neutral nitrate oil is subjected to a dehydration and drying treatment to obtain dry nitrate oil.

[0112] Crystallization is:

[0113] The dried nitric acid oil is subjected to distillation separation treatment to remove o-nitrochlorobenzene, and then cooled and crystallized to obtain p-nitrochlorobenzene.

[0114] Example 4

[0115] A production process of p-nitrochlorobenzene, comprising: using chlorobenzene and nitric acid as raw materials to carry out a nitration reaction under the catalytic action of a catalyst to generate a mixture containing p-nitrochlorobenzene and o-nitrochlorobenzene, and then post-treating the mixture of p-nitrochlorobenzene and o-nitrochlorobenzene to obtain a p-nitrochlorobenzene product;

[0116] The reaction temperature was 126°C, the reaction time was 1.8 hours, the reaction pressure was 0.6 MPa in the initial 30 minutes, and the pressure was 0.35 MPa after 30 minutes.

[0117] Wherein chlorobenzene and nitric acid are fed in a molar ratio of 1:1-2;

[0118] The catalyst is sulfuric acid, and the amount of catalyst added is 3.6% of the mass of chlorobenzene.

[0119] Post-treatment includes: neutralization, washing, dehydration, and crystallization;

[0120] Wherein, before post-treatment, the mixture containing p-nitrochlorobenzene and o-nitrochlorobenzene is separated into a nitrate oil phase and an acid phase, and the nitrate oil phase is post-treated.

[0121] Neutralization:

[0122] Add the nitrate oil phase into the alkali washing pot for alkali washing;

[0123] Alkali washing adopts: sodium hydroxide solution is used to carry out alkaline washing treatment on the nitrate oil phase, and the sodium hydroxide solution and the nitrate oil phase are mixed and alkaline washed in a mass ratio of 2:1 to form a neutralization reaction, and then water-oil separation is performed to obtain alkaline nitrate oil;

[0124] Wherein, the concentration of sodium hydroxide solution is 5 mol / L.

[0125] Washing:

[0126] The alkaline nitrate oil is mixed with water and washed with water. After the washing is completed, it is separated by a water washing separator to obtain neutral nitrate oil.

[0127] Dehydration for:

[0128] The neutral nitrate oil is subjected to a dehydration and drying treatment to obtain dry nitrate oil.

[0129] Crystallization is:

[0130] The dried nitric acid oil is subjected to distillation separation treatment to remove o-nitrochlorobenzene, and then cooled and crystallized to obtain p-nitrochlorobenzene.

[0131] Example 5

[0132] A production process of p-nitrochlorobenzene, comprising: using chlorobenzene and nitric acid as raw materials to carry out a nitration reaction under the catalytic action of a catalyst to generate a mixture containing p-nitrochlorobenzene and o-nitrochlorobenzene, and then post-treating the mixture of p-nitrochlorobenzene and o-nitrochlorobenzene to obtain a p-nitrochlorobenzene product;

[0133] The reaction temperature was 130°C, the reaction time was 2 hours, the reaction pressure was 0.6 MPa in the initial 30 minutes, and the pressure was 0.4 MPa after 30 minutes.

[0134] Wherein chlorobenzene and nitric acid are fed in a molar ratio of 1:2;

[0135] The catalyst is sulfuric acid, and the amount of the catalyst added is 4% of the mass of chlorobenzene.

[0136] Post-treatment includes: neutralization, washing, dehydration, and crystallization;

[0137] Wherein, before post-treatment, the mixture containing p-nitrochlorobenzene and o-nitrochlorobenzene is separated into a nitrate oil phase and an acid phase, and the nitrate oil phase is post-treated.

[0138] Neutralization:

[0139] Add the nitrate oil phase into the alkali washing pot for alkali washing;

[0140] Alkali washing adopts: sodium hydroxide solution is used to carry out alkaline washing treatment on the nitrate oil phase, and the sodium hydroxide solution and the nitrate oil phase are mixed and alkaline washed in a mass ratio of 2:1 to form a neutralization reaction, and then water-oil separation is performed to obtain alkaline nitrate oil;

[0141] Wherein, the concentration of sodium hydroxide solution is 5 mol / L.

[0142] Washing:

[0143] The alkaline nitrate oil is mixed with water and washed with water. After the washing is completed, it is separated by a water washing separator to obtain neutral nitrate oil.

[0144] Dehydration for:

[0145] The neutral nitrate oil is subjected to a dehydration and drying treatment to obtain dry nitrate oil.

[0146] Crystallization is:

[0147] The dried nitric acid oil is subjected to distillation separation treatment to remove o-nitrochlorobenzene, and then cooled and crystallized to obtain p-nitrochlorobenzene.

[0148] Comparative Example 1:

[0149] The difference from Example 1 is that the pressure during the whole reaction is a fixed value, which is the same as the pressure value after 30 minutes.

[0150] Comparative Example 2:

[0151] The difference from Example 1 is that the pressure during the whole reaction is a fixed value, which is the same as the initial pressure value at 30 min.

[0152] Comparative Example 3:

[0153] The difference from Example 1 is that the catalyst is replaced with an equal amount of sulfuric acid;

[0154] test

[0155] The purity of p-nitrochlorobenzene obtained by the process of the embodiment is tested:

[0156] Table 1

[0157] purity% Example 1 99.3 Example 2 99.8 Example 3 99.1 Example 4 99.5 Example 5 99.0 Comparative Example 1 95.2 Comparative Example 2 93.1 Comparative Example 3 90.4

[0158] As can be seen from Table 1, the p-nitrochlorobenzene obtained by the process of the present invention has a higher purity.

[0159] The yield of p-nitrochlorobenzene crystals obtained by the total mass of dry nitre oil in the embodiment process was tested:

[0160] Table 2

[0161]

[0162]

[0163] It can be seen from Table 2 that the p-nitrochlorobenzene crystal yield obtained by the process of the present invention is higher.

[0164] Based on Example 1, the effects of different 30-min initial reaction pressure settings on the crystallization yield of p-nitrochlorobenzene are compared:

[0165] Table 3

[0166] 30min initial pressure / MPa Crystallization yield% 0.2 60.6 0.3 61.0 0.4 61.3 0.5 62.5 0.6 63.3 0.7 62.4 0.8 62.0

[0167] It can be seen from Table 3 that different 30 min initial reaction pressures in the present invention have a significant effect on the crystallization yield of p-nitrochlorobenzene.

[0168] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A production process for p-nitrochlorobenzene, characterized in that: include: Using chlorobenzene and nitric acid as raw materials, a nitration reaction is carried out under the catalytic action of a catalyst to generate a mixture containing p-nitrochlorobenzene and o-nitrochlorobenzene, and then the p-nitrochlorobenzene and o-nitrochlorobenzene mixture is post-treated to obtain a p-nitrochlorobenzene product; The reaction temperature is 125-130°C, the reaction time is 1.5-2 hours, the reaction pressure is 0.6MPa in the initial 30 minutes, and the pressure is 0.3-0.4MPa after 30 minutes.

2. A production process for p-nitrochlorobenzene according to claim 1, characterized in that: The catalyst preparation method is: First, bamboo powder is added to a sodium hydroxide solution and stirred for 40 minutes, then filtered, washed with water until neutral, and dried until the moisture content is less than 10% to obtain pretreated bamboo powder; Among them, the mixing ratio of bamboo powder and sodium hydroxide solution is 30g:120mL; The mass fraction of the sodium hydroxide solution is 3.5%; The pretreated bamboo powder obtained above is subjected to steam explosion treatment, and then dried to a moisture content of less than 10%, and then carbonized under an inert atmosphere to obtain a carbide; Among them, the steam explosion pressure is 3MPa, the temperature is 228℃, and the steam explosion time is 1 hour; The inert atmosphere was nitrogen, the carbonization temperature was 420°C, and the time was 8 hours; The carbide and concentrated sulfuric acid are mixed, heated to react for 2 hours, filtered, and dried to obtain; The mass ratio of carbide and concentrated sulfuric acid is 1:2; The mass fraction of concentrated sulfuric acid is 80% and the reaction temperature is 85°C.

3. A production process for p-nitrochlorobenzene according to claim 2, characterized in that: The specific chemical equation of the nitration reaction is:

4. A production process for p-nitrochlorobenzene according to claim 1, characterized in that: The post-treatment includes: neutralization, water washing, dehydration, and crystallization; Wherein, before post-treatment, the mixture containing p-nitrochlorobenzene and o-nitrochlorobenzene is separated into a nitrate oil phase and an acid phase, and the nitrate oil phase is post-treated.

5. A production process for p-nitrochlorobenzene according to claim 4, characterized in that: The neutralization is: Add the nitrate oil phase into the alkali washing pot for alkali washing; Alkali washing adopts: sodium hydroxide solution is used to carry out alkaline washing treatment on the nitrate oil phase, and the sodium hydroxide solution and the nitrate oil phase are mixed and alkaline washed in a mass ratio of 2:1 to form a neutralization reaction, and then water-oil separation is performed to obtain alkaline nitrate oil; Wherein, the concentration of sodium hydroxide solution is 5 mol / L.

6. A production process for p-nitrochlorobenzene according to claim 4, characterized in that: Washing: The alkaline nitrate oil is mixed with water and washed with water. After the washing is completed, it is separated by a water washing separator to obtain neutral nitrate oil.

7. A production process for p-nitrochlorobenzene according to claim 4, characterized in that: Dehydration for: The neutral nitrate oil is subjected to a dehydration and drying treatment to obtain dry nitrate oil.

8. A production process for p-nitrochlorobenzene according to claim 4, characterized in that: Crystallization is: The dried nitric acid oil is subjected to distillation separation treatment to remove o-nitrochlorobenzene, and then cooled and crystallized to obtain p-nitrochlorobenzene.

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