JP2013095701A - Method of producing 4-nitro-diphenylamine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of producing 4-nitro-diphenylamine capable of carrying out easily and simply aftertreatment for a reaction mixture.SOLUTION: The method of producing the 4-nitro-diphenylamine is constituted to react aniline with nitrobenzene in the presence of a catalyst with an alkali metal carbonate carried on a carrier. At least one kind selected from the group comprising potassium carbonate, lithium carbonate, sodium carbonate and cesium carbonate is preferable as the alkali metal carbonate, and at least one kind selected from the group comprising alumina, zirconia, silica, titania and activated carbon is preferable as the carrier, in the method.

Description

  The present invention relates to a process for producing 4-nitrodiphenylamine from aniline and nitrobenzene. 4-Nitrodiphenylamine is useful as a raw material for azo dyes. Further, 4-nitrodiphenylamine is converted to 4-aminodiphenylamine by hydrogenation, and 4-alkyldiphenylamine is alkylated to produce 4-alkylaminodiphenylamine useful as an antioxidant for natural rubber and synthetic rubber. Can be obtained.

  As a method for producing 4-nitrodiphenylamine, for example, Patent Document 1 discloses a method of reacting aniline with nitrobenzene in the presence of quaternary ammonium hydroxide such as tetramethylammonium hydroxide dihydrate. Patent Document 2 discloses a method of reacting aniline with nitrobenzene in the presence of an alkali metal hydroxide such as potassium hydroxide and a quaternary ammonium salt such as tetramethylammonium chloride. Patent Documents 3 to 5 disclose methods for reacting aniline and nitrobenzene using montmorillonite, hydrotalcite or ruthenium-supported alumina in the presence of potassium hydroxide in a dimethyl sulfoxide solvent. Yes.

Japanese National Patent Publication No. 6-508630 JP 2005-515163 A JP 2007-176811 A JP 2007-176812 A JP 2007-302588 A

  However, in the above conventional method, a large amount of compounds that can be dissolved in the reaction mixture after the reaction, such as alkali metal hydroxide, quaternary ammonium hydroxide, and quaternary ammonium salt, must be used. There are problems such as complicated steps and operations required for post-treatment of the reaction mixture such as separation and recovery of the compounds and purification for preventing the compounds from remaining in the target product, which is not industrially preferable.

  Then, the objective of this invention is providing the manufacturing method of 4-nitrodiphenylamine which can post-process the reaction mixture obtained after reaction easily.

  As a result of intensive studies to achieve the above object, the present inventor has found that the post-treatment of the reaction mixture can be simplified by reacting aniline with nitrobenzene in the presence of a specific catalyst.

  That is, the present invention provides a method for producing 4-nitrodiphenylamine, which comprises reacting aniline and nitrobenzene in the presence of a catalyst in which an alkali metal carbonate is supported on a carrier.

  According to the present invention, it is industrially advantageous because 4-nitrodiphenylamine can be produced by simplifying the post-treatment of the reaction mixture obtained after the reaction.

  Hereinafter, the present invention will be described in detail. In the present invention, 4-nitrodiphenylamine is produced by reacting aniline and nitrobenzene in the presence of a catalyst in which an alkali metal carbonate is supported on a carrier.

  The catalyst used in the present invention is a catalyst in which an alkali metal carbonate is supported on a carrier (supported alkali metal carbonate catalyst). Examples of the alkali metal carbonate include potassium carbonate, lithium carbonate, sodium carbonate, cesium carbonate, and the like. Among these, potassium carbonate is preferable. Only one alkali metal carbonate may be used, or two or more alkali metal carbonates may be used in combination.

  Examples of the carrier include alumina, zirconia, silica, titania, activated carbon, and the like. Among these, alumina is preferable. When alumina is contained in the carrier, examples of alumina include α-alumina, γ-alumina, θ-alumina, δ-alumina, β-alumina, amorphous alumina, boehmite, and the like. You may mix and use a seed | species or more. Among these, γ-alumina is preferable. Only one type of carrier may be used, or two or more types may be used in combination.

  The content of the alkali metal carbonate in the catalyst is usually 1 to 60% by weight, preferably 10 to 40% by weight, based on the total amount of the catalyst, in that 4-nitrodiphenylamine can be produced with good yield. More preferably, it is 20 to 30% by weight. When two or more alkali metal carbonates are used in combination, the total content may be within the above range.

  Examples of the method of supporting the alkali metal carbonate on the carrier include a method of contacting the carrier with a solution containing an alkali metal carbonate. In the contact treatment, the temperature during the treatment is preferably 0 to 100 ° C., and the pressure during the treatment is preferably 0.001 to 1.0 MPa. Such contact treatment can be performed in an air atmosphere or in an inert gas atmosphere such as nitrogen, helium, argon, or oxygen dioxide. Examples of the solvent used for preparing the solution include water; alcohols such as methanol and ethanol. Only 1 type may be used for a solvent and it may use 2 or more types together. The usage-amount of a solvent is suitably adjusted with the alkali metal carbonate to be used.

  Examples of the contact treatment include mixing, impregnation or immersion. Examples of the method for contact treatment with the solution include (A) a method in which a support is impregnated with a solution containing an alkali metal carbonate, and (B) a method in which the support is immersed in a solution containing an alkali metal carbonate. However, the method (A) is preferred. In the method (B), the immersion may be performed while stirring. What is necessary is just to adjust suitably the usage-amount of a support | carrier and an alkali metal carbonate so that content of the alkali metal carbonate in the catalyst obtained may become the said range.

  Before the contact treatment, the support is preferably subjected to a treatment for holding at a temperature of 200 to 700 ° C. in an inert gas, oxidizing gas or reducing gas atmosphere as pre-baking.

  It is preferable that an alkali metal carbonate is supported on the carrier, dried, and then fired. As the drying method, a conventionally known method can be employed. Specifically, a known method such as an evaporating and drying method, a box-type dryer, a drum-type aeration dryer, a spray dryer, an air dryer or the like can be used. A drying method using a drying apparatus can be used, and a combination of an evaporation to dryness method and a drying method using a known drying apparatus can also be used. As the evaporation / drying method, for example, a method of distilling off the solvent from a slurry of the carrier and the solution containing the alkali metal carbonate is preferably used. A drying temperature is 100-200 degreeC normally, Preferably it is 110-150 degreeC. The drying may be performed under normal pressure, under pressure, or under reduced pressure, but is preferably under normal pressure or under reduced pressure. Such drying can be performed in an air atmosphere or an inert gas atmosphere such as nitrogen, helium, argon, or oxygen dioxide.

  The calcination can be performed in an inert gas, oxidizing gas, or reducing gas atmosphere. The firing temperature in firing is usually 300 to 1000 ° C, preferably 300 to 800 ° C. Moreover, you may perform this baking in a multistep within the range of 300-1000 degreeC by inert gas, oxidizing gas, or reducing gas atmosphere.

  Examples of the inert gas used for the pre-baking or baking include nitrogen, carbon dioxide, helium, argon, and the like, and diluted with water vapor as necessary. Among these, nitrogen is preferable as the inert gas. The oxidizing gas used for the pre-firing or the calcining is a gas containing an oxidizing substance, and examples thereof include an oxygen-containing gas. As the oxygen source, air or pure oxygen is usually used. Diluted with inert gas or water vapor. Of these, air is preferable as the oxidizing gas. The reducing gas used for pre-firing or calcination is a gas containing a reducing substance, and examples thereof include a hydrogen-containing gas, a carbon monoxide-containing gas, a hydrocarbon-containing gas, and the concentration thereof is, for example, inert. It is adjusted with gas or water vapor. Among them, the reducing gas is preferably a hydrogen-containing gas or a carbon monoxide-containing gas.

  The shape of the catalyst is not particularly limited, and may be in the form of a powder, or may be a molded body having a shape such as a granular shape or a tablet shape. In particular, from the viewpoint of ease of handling, a granular molded body and a tablet-shaped molded body are preferable.

  The usage-amount of the said catalyst is 1-100g normally with respect to 1 mol of nitrobenzene, Preferably it is 3-50g.

  The ratio of aniline and nitrobenzene used as raw materials is usually 1:30 to 30: 1 as aniline: nitrobenzene (molar ratio), preferably 1:10 to 10: 1. The reaction solvent can be used as necessary, and examples thereof include dimethyl sulfoxide, dimethylformamide, N-methyl-2-pyrrolidone, N, N-dimethylformamide, tetrahydrofuran, t-butanol, toluene and the like. Can be mentioned.

  The reaction temperature is usually 100 to 500 ° C, preferably 120 to 250 ° C. The reaction pressure is usually 0.01 to 5.0 MPa in absolute pressure.

  In the reaction, a gas inert to the reaction may be present. Examples of the inert gas include nitrogen, helium, air, and argon.

  The reaction may be performed in a batch system, a semi-batch system, a continuous system, or a combination of a batch system, a semi-batch system and a continuous system. In the case of a semi-batch type, it is preferable to carry out the reaction while supplying the reaction raw material into a stirring / mixing type or loop type reactor. In the case of a continuous type, a method of extracting the liquid phase of the reaction mixture while supplying the reaction raw material into a stirring / mixing type or loop type reactor, or a fixed bed flow for circulating the reaction raw material in a fixed bed reactor filled with a catalyst. It is desirable to carry out the above reaction in terms of productivity and operability. In the fixed bed flow system, as the fixed bed reactor used, various flow-type fixed bed reactors in which a raw material supply port and a reaction liquid take-out port are provided in the reactor can be used. The number of reaction tubes is not particularly limited, and either a single tube fixed bed reactor or a multi-tube fixed bed reactor can be used. Moreover, a fixed bed reactor of an adiabatic system or a heat exchange system can be used.

  Regarding the post-treatment operation of the reaction mixture obtained by the above reaction, the reaction mixture is filtered to recover the catalyst as a filter residue, and the filtrate is washed as necessary and subjected to separation and purification operations such as distillation, distribution, and crystallization. Just do it. The recovered catalyst can be reused. In the present invention, compounds such as alkali metal hydroxides such as potassium hydroxide, quaternary ammonium hydroxides such as tetramethylammonium hydroxide dihydrate, and quaternary ammonium salts such as tetramethylammonium chloride are not used. Therefore, separation and recovery of compounds such as alkali metal hydroxide, quaternary ammonium hydroxide and quaternary ammonium salt from the reaction mixture is not required, and the target product is alkali metal hydroxide and quaternary hydroxide. This is industrially advantageous because it eliminates the need for a purification step in order not to leave compounds such as ammonium and quaternary ammonium salts, and simplifies the post-treatment. Usually, 4-nitrodiphenylamine is recovered from the reaction mixture by filtering the reaction mixture, recovering the catalyst as a filter residue, and then recovering unreacted raw material as a fraction from the filtrate by distillation or the like, and then recovering 4-nitro. Diphenylamine can be recovered as a fraction, and a high-boiling byproduct can be separated as a residue. By such fractional distillation, the target 4-nitrodiphenylamine can be easily obtained. Moreover, the reaction mixture containing the unreacted raw material and the unreacted raw material recovered as a fraction can be recycled. The filtrate may be subjected to hydrogenation for producing 4-aminodiphenylamine as it is or after recovering unreacted raw material as a fraction by distillation or the like.

  Examples of the present invention will be shown below, but the present invention is not limited thereto.

  The analysis of 4-nitrodiphenylamine was performed by gas chromatography, and the yield of 4-nitrodiphenylamine was calculated by the following formula, where X was the number of moles of nitrobenzene supplied and Y was the number of moles of 4-nitrodiphenylamine produced. .

Yield of 4-nitrodiphenylamine (%) = [Y / X] × 100

Reference Example 1 (Preparation of catalyst A)
While filling 10.0 g of powdery γ-alumina (trade name “AC-11”, manufactured by Sumitomo Chemical Co., Ltd.) into a quartz tube and circulating nitrogen at a flow rate of 50 Nml / min, 2 ° The temperature was raised over time, maintained at 500 ° C. for 16 hours, and then cooled to room temperature. 9.31 g of the obtained powdery alumina carrier was transferred to a beaker, and 5.0 g of 20 wt% potassium carbonate aqueous solution was added dropwise with stirring. The obtained solid was filled in a quartz tube, heated from room temperature to 130 ° C. over 1 hour while flowing nitrogen at a flow rate of 50 Nml / min, kept at 130 ° C. for 16 hours and dried, then 575 The mixture was heated to 2 ° C. over 2 hours and then kept at 575 ° C. for 24 hours, and then cooled to room temperature to prepare 9.77 g of catalyst A (potassium carbonate content: 10% by weight).

Reference Example 2 (Preparation of catalyst B)
9.29 g of catalyst B (potassium carbonate content: 18 wt%) was prepared in the same manner as in Reference Example 1 except that the amount of 20 wt% potassium carbonate aqueous solution was changed from 5.0 g to 10.0 g.

Reference Example 3 (Preparation of catalyst C)
10.85 g of catalyst C (potassium carbonate content: 21 wt%) was prepared in the same manner as in Reference Example 1 except that 5.0 g of 20 wt% potassium carbonate aqueous solution was changed to 7.5 g of 33 wt% potassium carbonate aqueous solution. .

Reference Example 4 (Preparation of catalyst D)
11.30 g of catalyst D (potassium carbonate content: 24 wt%) was prepared in the same manner as in Reference Example 1 except that 5.0 g of 20 wt% potassium carbonate aqueous solution was changed to 10.0 g of 30 wt% potassium carbonate aqueous solution. .

Reference Example 5 (Preparation of catalyst E)
The catalyst E (potassium carbonate content: 21% by weight) 10.94 g was calcined in the same manner as in Reference Example 3 except that the temperature was raised to 500 ° C. over 2 hours and then changed to hold at 500 ° C. for 24 hours. Prepared.

Reference Example 6 (Preparation of catalyst F)
Catalyst F (potassium carbonate content: 21% by weight) 10 in the same manner as in Reference Example 3 except that the temperature was raised to 575 ° C. over 2 hours and then changed to hold at 575 ° C. for 12 hours. .87 g was prepared.

Example 1
In a 100 ml round bottom flask, 2.62 g of catalyst A, 24.74 g (0.27 mol) of aniline and 32.72 g (0.27 mol) of nitrobenzene were placed and stirred under a nitrogen atmosphere at 150.degree. The temperature was raised to ° C. Stirring was continued for 10 hours after the temperature reached 150 ° C., and then cooled to room temperature. As a result of filtering the obtained mixture and analyzing the filtrate, the yield of 4-nitrodiphenylamine was 1.0%. Table 1 shows the transition of the yield of 4-nitrodiphenylamine every hour in the stirring for 10 hours.

Example 2
The same operation as in Example 1 was performed except that the catalyst B was used instead of the catalyst A. The yield of 4-nitrodiphenylamine was 1.2%. Table 1 shows the transition of the yield of 4-nitrodiphenylamine every hour in the stirring for 10 hours.

Example 3
The same operation as in Example 1 was performed except that the catalyst C was used instead of the catalyst A. The yield of 4-nitrodiphenylamine was 1.4%. Table 1 shows the transition of the yield of 4-nitrodiphenylamine every hour in the stirring for 10 hours.

Example 4
The same operation as in Example 1 was performed except that catalyst D was used instead of catalyst A. The yield of 4-nitrodiphenylamine was 1.4%. Table 1 shows the transition of the yield of 4-nitrodiphenylamine every hour in the stirring for 10 hours.

Example 5
The same operation as in Example 1 was performed except that the catalyst E was used instead of the catalyst A. The yield of 4-nitrodiphenylamine was 1.1%. Table 1 shows the transition of the yield of 4-nitrodiphenylamine every hour in the stirring for 10 hours.

Example 6
The same operation as in Example 1 was performed except that the catalyst F was used instead of the catalyst A. The yield of 4-nitrodiphenylamine was 1.2%. Table 1 shows the transition of the yield of 4-nitrodiphenylamine every hour in the stirring for 10 hours.

Comparative Example 1
The same operation as in Example 1 was performed except that hydrotalcite [Mg ₆ Al ₂ (OH) ₁₆ CO ₃ .4H ₂ O; manufactured by Wako Pure Chemical Industries, Ltd.] was used in place of the catalyst A. The yield of 4-nitrodiphenylamine was 0.0%. Table 1 shows the transition of the yield of 4-nitrodiphenylamine every hour in the stirring for 10 hours.

Claims (6)

  A process for producing 4-nitrodiphenylamine, comprising reacting aniline and nitrobenzene in the presence of a catalyst in which an alkali metal carbonate is supported on a carrier.   2. The production method according to claim 1, wherein the alkali metal carbonate is at least one selected from the group consisting of potassium carbonate, lithium carbonate, sodium carbonate, and cesium carbonate.   The production method according to claim 1, wherein the carrier is at least one selected from the group consisting of alumina, zirconia, silica, titania, and activated carbon.   4. The catalyst according to claim 1, wherein the catalyst is obtained by supporting an alkali metal carbonate on a support, drying, and then calcining at 300 to 1000 ° C. in an inert gas atmosphere. The manufacturing method as described in.   The manufacturing method according to claim 4, wherein the inert gas is nitrogen.   The production method according to any one of claims 1 to 5, wherein the reaction temperature is 100 to 500 ° C.