JPH0794412B2 - Method for producing aromatic nitro compound - Google Patents
Method for producing aromatic nitro compoundInfo
- Publication number
- JPH0794412B2 JPH0794412B2 JP62162248A JP16224887A JPH0794412B2 JP H0794412 B2 JPH0794412 B2 JP H0794412B2 JP 62162248 A JP62162248 A JP 62162248A JP 16224887 A JP16224887 A JP 16224887A JP H0794412 B2 JPH0794412 B2 JP H0794412B2
- Authority
- JP
- Japan
- Prior art keywords
- benzene
- reaction
- isomer
- nitration
- nitric acid
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts
Landscapes
- Catalysts (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Description
【発明の詳細な説明】 （産業上の利用分野） 本発明は、芳香族ニトロ化合物の製造方法に関するもの
で、さらに詳しくは、ベンゼンまたはベンゼン誘導体を
結晶性シリカ分子フルイ含有触媒の存在下に、硝酸水溶
液を用いて液相状態でニトロ化することを特徴とする芳
香族ニトロ化合物の製造方法に関するものである。TECHNICAL FIELD The present invention relates to a method for producing an aromatic nitro compound, and more specifically, to the addition of benzene or a benzene derivative in the presence of a crystalline silica molecule sieve-containing catalyst. The present invention relates to a method for producing an aromatic nitro compound, which comprises nitrating in a liquid phase using an aqueous nitric acid solution.
（従来の技術） 芳香族ニトロ化合物は、芳香族アミノ化合物の原料等に
用いられる有用な有機化学品の中間体である。芳香族ニ
トロ化合物の工業的製法は、硝酸と濃硫酸の混合物であ
る混酸を用い実施されているが、多量の硫酸を用いるた
め、廃硫酸や廃水処理等の問題がある。一方、廃硫酸を
発生させない方法として気相ニトロ化法が提案されてい
る。例えば、特開昭50−121234号公報には、シリカ・ア
ルミナやアルミノシリケートを触媒に用い、ハロベンゼ
ンを気相ニトロ化する方法が、特開昭54−95521号公報
には、約５〜10Åの細孔径を有する分子フルイ触媒の存
在下で、クロロベンゼンを気相ニトロ化する方法が、特
開昭58−157748号公報、特開昭59−216851号公報には、
アルミノシリケートゼオライトを触媒とし、芳香族化合
物を気相ニトロ化する方法が開示されている。(Prior Art) Aromatic nitro compounds are intermediates of useful organic chemicals used as raw materials for aromatic amino compounds. The industrial production method of aromatic nitro compounds is carried out using a mixed acid which is a mixture of nitric acid and concentrated sulfuric acid, but since a large amount of sulfuric acid is used, there are problems such as waste sulfuric acid and wastewater treatment. On the other hand, a gas phase nitration method has been proposed as a method that does not generate waste sulfuric acid. For example, in JP-A-50-121234, there is disclosed a method of vapor-phase nitration of halobenzene using silica-alumina or aluminosilicate as a catalyst. In the presence of a molecular sieve catalyst having a pore size, a method of gas phase nitration of chlorobenzene, JP-A-58-157748, JP-A-59-216851,
A method for vapor-phase nitration of aromatic compounds using aluminosilicate zeolite as a catalyst is disclosed.
（発明が解決しようとする問題点） 公知の気相ニトロ化方法は、廃硫酸等の処理の問題解決
にはつながるが、いずれも比較的高い反応温度を必要と
しているにもかかわらず、触媒当りのニトロ化合物の収
率も比較的低く、満足できる水準にない。さらに、気相
で比較的高い温度条件のためニトロ化剤の熱分解が生
じ、ニトロ化剤効率が低くなるし、発生する酸化窒素ガ
スは有害であり廃ガス処理が必要となる等の問題も有し
ている。(Problems to be Solved by the Invention) Although the known gas-phase nitration method leads to solving the problem of the treatment of waste sulfuric acid, etc. The yield of the nitro compound is relatively low and not at a satisfactory level. In addition, there is a problem that thermal decomposition of the nitrating agent occurs due to a relatively high temperature condition in the gas phase, the efficiency of the nitrating agent becomes low, and the generated nitric oxide gas is harmful and requires waste gas treatment. Have
気相ニトロ化反応はインダストリー・アンド・エンジニ
ヤリングケミストリー,June,1936,662ページ等に記載の
反応式として、次式にしたがつていると推定されてい
る。The gas-phase nitration reaction is presumed to be according to the following equation as the reaction equation described in Industry and Engineering Chemistry, June, 1936 , p.662, etc.
また、硝酸をニトロ化剤として用いても、硝酸は気相で
は次式にしたがつて酸化窒素への分解が生じること、水
和した硝酸はより安定であることがメラー著「インオー
ガニツク・アンド・セオレテイカルケミストリー」８
巻,572頁等に記載されている。 Moreover, even if nitric acid is used as a nitrating agent, nitric acid decomposes to nitric oxide in the gas phase according to the following formula, and hydrated nitric acid is more stable. And Theoretical Chemistry "8
Vol., Page 572.
4HNO3→4NO2＋2H2O＋O2 ……（２） したがつて、気相ニトロ化反応においては、酸化窒素ガ
スの生成は本質的に避けられないものである。4HNO 3 → 4NO 2 + 2H 2 O + O 2 (2) Therefore, in the gas phase nitration reaction, the production of nitric oxide gas is essentially unavoidable.
これら酸素や酸化窒素の発生は、ニトロ化反応以外の副
反応を生じる恐れも有している。The generation of oxygen and nitric oxide may cause side reactions other than the nitration reaction.
（問題点を解決するための手段） 本発明者らは、比較的低い温度で、かつ高い収率が得ら
れる芳香族化合物のニトロ化方法について鋭意検討を加
えた結果、ベンゼンまたはベンゼン誘導体を、結晶性シ
リカ分子フルイを触媒とし、硝酸水溶液を用いて液相状
態でニトロ化することにより、目的が達成されることを
見い出したものである。すなわち、硝酸の水溶液をニト
ロ化剤に用い、しかも、液相状態で反応させることによ
り、酸化窒素等の有害ガスの発生を抑制でき、かつ前述
の触媒が比較的低温の液相反応に高い活性を有すること
を見い出したものである。(Means for Solving the Problems) The present inventors have conducted extensive studies on a nitration method of an aromatic compound capable of obtaining a high yield at a relatively low temperature, and as a result, benzene or a benzene derivative was It has been found that the object can be achieved by nitrating in the liquid phase with an aqueous nitric acid solution using crystalline silica molecular sieve as a catalyst. That is, by using an aqueous solution of nitric acid as the nitrating agent and reacting in a liquid phase state, it is possible to suppress the generation of harmful gases such as nitric oxide, and the above-mentioned catalyst is highly active in a liquid phase reaction at a relatively low temperature. Is found to have.
本発明方法は、従来公知のニトロ化方法に比べ、ジニト
ロ体等の副生物がほとんど生成しない特徴も有してい
る。また、モノハロベンゼン等モノ置換ベンゼンのニト
ロ化において生成するオルト体、メタ体、パラ体の異性
体分布において有用なパラ置換体を、高い選択率で得る
ことができる等の特徴も合せ有している。The method of the present invention also has a feature that byproducts such as dinitro compounds are scarcely produced as compared with conventionally known nitration methods. In addition, it also has the feature that para-substituted products useful in the isomer distribution of ortho-, meta-, and para-forms generated in the nitration of mono-substituted benzenes such as monohalobenzene can be obtained with high selectivity. ing.
本発明においては、芳香族化合物としてベンゼンおよび
ベンゼン誘導体が用いられる。ベンゼン誘導体として
は、トルエン、エチルベンゼン、キシレン等のアルキル
ベンゼン、モノクロロベンゼン、ジクロロベンゼン、モ
ノブロモベンゼン、ジブロモベンゼン、モノヨウ化ベン
ゼン、ジヨウ化ベンゼン等のハロゲン化ベンゼン類、安
息香酸、フタール酸等のアリールカルボン酸、そのエス
テル類、ビフエニル酸を例示することができる。これら
芳香族化合物は、液相状態で反応に供する。反応系には
必要ならば、これら芳香族化合物を溶解させる溶媒を加
えてもよい。In the present invention, benzene and a benzene derivative are used as the aromatic compound. Examples of the benzene derivative include alkylbenzenes such as toluene, ethylbenzene and xylene, halogenated benzenes such as monochlorobenzene, dichlorobenzene, monobromobenzene, dibromobenzene, monoiodinated benzene and diiodinated benzene, arylcarboxylic acids such as benzoic acid and phthalic acid. Examples thereof include acids, their esters, and biphenyl acid. These aromatic compounds are used for the reaction in a liquid phase state. If necessary, a solvent that dissolves these aromatic compounds may be added to the reaction system.
本発明で用いるニトロ化剤は硝酸水溶液であつて、硝酸
濃度としては10〜98％、好ましくは30〜90％のものであ
る。硝酸濃度が低くすぎると反応率が低く、98％を超え
るとNOx等の発生が生じ、ニトロ化剤の効率が減少す
る。The nitrating agent used in the present invention is an aqueous nitric acid solution having a nitric acid concentration of 10 to 98%, preferably 30 to 90%. If the nitric acid concentration is too low, the reaction rate will be low, and if it exceeds 98%, the generation of NO x will occur and the efficiency of the nitrating agent will decrease.
硝酸の使用割合は、ベンゼンまたはベンゼン誘導体１モ
ルに対して0.1〜10モル、好ましくは0.2〜3.0モルが用
いられる。The nitric acid is used in an amount of 0.1 to 10 mol, preferably 0.2 to 3.0 mol, per 1 mol of benzene or a benzene derivative.
反応温度としては、用いられるベンゼンあるいはベンゼ
ン誘導体により異なるが、通常20〜150℃、好ましくは4
0〜120℃である。The reaction temperature varies depending on the benzene or benzene derivative used, but is usually 20 to 150 ° C., preferably 4
It is 0 to 120 ° C.
反応圧力は通常、常圧で実施されるが、反応系を液相に
保つため加圧にしてもさしつかえない。The reaction pressure is usually atmospheric pressure, but it may be increased to maintain the reaction system in the liquid phase.
本発明で用いる触媒としては、結晶性シリカ分子フルイ
を含有するものである。結晶性シリカ分子フルイの代表
例としては、シリカライトを挙げることができる。ケイ
素の一部を遷移金属元素、例えば、チタン、バナジン、
クロム、鉄、銅、希土類等で置換した結晶性シリカ分子
フルイも同様に用いられる。特に細孔径が約５〜6.5Å
の中間細孔径を有するものが好都合に用いられる。The catalyst used in the present invention contains crystalline silica molecular sieve. Silicalite can be mentioned as a typical example of the crystalline silica molecular sieve. A portion of silicon is a transition metal element, such as titanium, vanadine,
A crystalline silica molecular sieve substituted with chromium, iron, copper, rare earth or the like is also used. Especially the pore size is about 5 to 6.5Å
Those having an intermediate pore size of 3 are conveniently used.
これら触媒の使用形態としては、懸濁状態あるいは固定
床方式等、通常の液相反応に用いられる形態で用いるこ
とができる。触媒の使用量としては、流通方式の場合
は、ベンゼンまたはベンゼン誘導体と硝酸の合計基準に
対して0.05〜20Hr-1の重量空間速度（WHSV）、好ましく
は0.1〜10Hr-1の重量空間速度（WHSV）が用いられる。
懸濁状態で用いる場合は、ベンゼンまたはベンゼン誘導
体の合計重量に対して５〜50重量％、好ましくは10〜30
重量％の触媒が用いられる。The catalyst may be used in a suspension state, a fixed bed system, or the like, which is used in ordinary liquid phase reactions. The amount of the catalyst, in the case of flow system, the weight hourly space velocity of 0.05～20Hr -1 to the total reference benzene or benzene derivative and nitric acid (WHSV), weight hourly space velocity of preferably 0.1 to 10 -1 ( WHSV) is used.
When used in a suspended state, it is 5 to 50% by weight, preferably 10 to 30% by weight based on the total weight of benzene or a benzene derivative.
Weight percent catalyst is used.
（発明の効果） 本発明の方法によれば、ベンゼンおよびベンゼン誘導体
のニトロ化を比較的低温で、かつ高い空時収率で実施す
ることができるとともに、廃硫酸の処理やNOx等の有害
ガスの処理も不要であり、その工業的利点は極めて大き
い。さらに、副生成物として取り扱いが困難なジニトロ
体の生成等もほとんどなく、分離操作上の利点もある。
さらに加えて、モノハロベンゼン等のニトロ化において
耐熱性高分子原料として有用なパラ異性体の選択率を高
められる等の利点も有している。(Effect of the Invention) According to the method of the present invention, nitration of benzene and a benzene derivative can be carried out at a relatively low temperature and a high space-time yield, and the treatment of waste sulfuric acid and the harmful effects of NO x, etc. No gas treatment is required, and its industrial advantage is extremely large. Further, there is almost no formation of a dinitro compound which is difficult to handle as a by-product, and there is an advantage in separation operation.
In addition, it has an advantage that the selectivity of para isomers useful as a heat-resistant polymer raw material can be increased in nitration of monohalobenzene and the like.
（実施例） 以下、実施例を挙げて本発明を具体的に示すが、本発明
は、これに限定されるものではない。(Examples) Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto.
実施例１ 市販のシリカライト（UCC製）を触媒に用い、クロロベ
ンゼンのニトロ化反応を行つた。Example 1 A commercially available silicalite (manufactured by UCC) was used as a catalyst to carry out the nitration reaction of chlorobenzene.
クロロベンゼン6.8g、61％硝酸12.5gおよびシリカライ
ト粉末4gを、ガラス製の50mlの撹拌器付きフラスコに入
れ、撹拌下90℃に加熱し、２時間反応を行なつた。冷却
後、有機層を取り出し、ガスクロマトグラフにより組成
分析を行なつた。その結果、クロロベンゼンの転化率は
14％で、クロロニトロベンゼンの異性体比率はオルト
体：メタ体：パラ体＝17.4:0.4:82.2であつた。なお、
ジニトロ体の生成は見られなかつた。Chlorobenzene (6.8 g), 61% nitric acid (12.5 g) and silicalite powder (4 g) were placed in a glass 50 ml flask equipped with a stirrer, heated to 90 ° C. under stirring and reacted for 2 hours. After cooling, the organic layer was taken out and the composition was analyzed by gas chromatography. As a result, the conversion rate of chlorobenzene is
At 14%, the isomer ratio of chloronitrobenzene was ortho isomer: meta isomer: para isomer = 17.4: 0.4: 82.2. In addition,
No formation of dinitro form was observed.
実施例２ 特開昭56−59619号にしたがつてSiO2/Cr2O3比60のクロ
ム置換結晶性シリカを合成し、常法にしたがつてＨ型と
した。このＨ型クロム置換結晶性シリカを触媒に用いた
以外は、実施例１と同様にクロロベンゼンのニトロ化反
応を行なつた。その結果、クロロベンゼンの転化率は15
％で、クロロニトロベンゼン異性体比率はオルト体：メ
タ体：パラ体＝20.3:0.4:79.4であつた。なお、ジニト
ロ体の生成は見られなかつた。Example 2 A chromium-substituted crystalline silica having a SiO 2 / Cr 2 O 3 ratio of 60 was synthesized according to JP-A-56-59619, and was made into an H type according to a conventional method. The nitration reaction of chlorobenzene was performed in the same manner as in Example 1 except that this H-type chromium-substituted crystalline silica was used as the catalyst. As a result, the conversion rate of chlorobenzene is 15
%, The chloronitrobenzene isomer ratio was ortho isomer: meta isomer: para isomer = 20.3: 0.4: 79.4. No formation of dinitro body was observed.
実施例３ 実施例１と同様に、ただし、クロロベンゼンに替えてベ
ンゼン5gを用いニトロ化反応を行なつた。反応温度は75
℃で行なつた。その結果、ニトロベンゼンの収率は22モ
ル％であり、ジニトロ体等の副生物は見られなかつた。Example 3 As in Example 1, the nitration reaction was carried out using 5 g of benzene instead of chlorobenzene. Reaction temperature is 75
Performed at ℃. As a result, the yield of nitrobenzene was 22 mol%, and byproducts such as dinitro compounds were not found.
実施例４ 石英反応管（10mmφ）に実施例１で用いたと同じシリカ
ライトを圧縮成形して10〜20メツシユに砕いたもの4gを
充填し、90℃に加熱し、クロロベンゼン2.0cc/Hr、61％
硝酸1cc/Hrを同時に供給し、ニトロ化反応を行なつた。
通液後６時間目の反応流出液（有機層）の分析結果は、
クロロベンゼンの転化率は12％で、クロロニトロベンゼ
ン異性体比率はオルト体：メタ体：パラ体＝12.8:0:87.
2であり、ジニトロ体の生成は見られなかつた。また、
反応中NOxガスの発生は見られなかつた。Example 4 A silica reaction tube (10 mmφ) was compression-molded with the same silicalite as used in Example 1 and charged with 4 g of crushed 10-20 mesh and heated to 90 ° C., and chlorobenzene 2.0 cc / Hr, 61 %
Nitric acid 1 cc / Hr was supplied at the same time to carry out the nitration reaction.
The analysis result of the reaction effluent (organic layer) 6 hours after the passage was
The conversion rate of chlorobenzene is 12%, and the isomer ratio of chloronitrobenzene is ortho body: meta body: para body = 12.8: 0: 87.
2 and no formation of dinitro form was observed. Also,
No generation of NO x gas was observed during the reaction.
実施例５ 石英反応管（15mmφ）に実施例４と同様にシリカライト
10gを充填し、55℃に加熱し、トルエンを2.5cc/Hr、70
％硝酸を0.6cc/Hrで供給し、ニトロ化反応を行なつた。
通液後10時間目の反応流出液（有機層）を分析した結
果、ニトロトルエンの収率は７モル％（トルエン基準）
であり、ニトロトルエン異性体比率はオルト体：メタ
体：パラ体＝34:1.5:64.5であり、ジニトロ体等の副生
物は見られなかつた。Example 5 Silicalite was added to a quartz reaction tube (15 mmφ) in the same manner as in Example 4.
Fill with 10g, heat to 55 ℃, and add toluene at 2.5cc / Hr, 70
% Nitric acid was supplied at 0.6 cc / Hr to carry out the nitration reaction.
As a result of analyzing the reaction effluent (organic layer) 10 hours after passing the liquid, the yield of nitrotoluene was 7 mol% (based on toluene).
The nitrotoluene isomer ratio was ortho isomer: meta isomer: para isomer = 34: 1.5: 64.5, and by-products such as dinitro isomer were not found.
実施例６ 実施例１と同様に、ただし、クロロベンゼン6.8gに替え
ブロモベンゼン9.0gを用い、90℃で４時間ニトロ化反応
を行なつた。その結果、ブロモニトロベンゼンの収率は
17モル％であり、異性体比率はオルト体：メタ体：パラ
体＝13.5:0.4:86.1であつた。なお、ジニトロ体の生成
は認められなかつた。Example 6 In the same manner as in Example 1, except that 6.8 g of chlorobenzene was replaced by 9.0 g of bromobenzene, a nitration reaction was carried out at 90 ° C. for 4 hours. As a result, the yield of bromonitrobenzene was
It was 17 mol%, and the isomer ratio was ortho isomer: meta isomer: para isomer = 13.5: 0.4: 86.1. No formation of dinitro body was observed.
Claims (3)
リカ分子フルイ触媒の存在下に、硝酸水溶液を用いて液
相状態でニトロ化することを特徴とする芳香族ニトロ化
合物の製造方法。1. A process for producing an aromatic nitro compound, which comprises nitrating benzene or a benzene derivative in the liquid phase with an aqueous nitric acid solution in the presence of a crystalline silica molecular sieve catalyst.
効細孔径を有するものである特許請求の範囲第１項記載
の方法。2. The method according to claim 1, wherein the crystalline silica molecular sieve has an effective pore size of 5 to 6.5Å.
特許請求の範囲第１項または第２項記載の方法。3. The method according to claim 1 or 2, wherein the benzene derivative is a mono-substituted benzene.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62162248A JPH0794412B2 (en) | 1987-07-01 | 1987-07-01 | Method for producing aromatic nitro compound |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62162248A JPH0794412B2 (en) | 1987-07-01 | 1987-07-01 | Method for producing aromatic nitro compound |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS649960A JPS649960A (en) | 1989-01-13 |
| JPH0794412B2 true JPH0794412B2 (en) | 1995-10-11 |
Family
ID=15750811
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62162248A Expired - Lifetime JPH0794412B2 (en) | 1987-07-01 | 1987-07-01 | Method for producing aromatic nitro compound |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0794412B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11602469B2 (en) | 2014-07-14 | 2023-03-14 | Exokinetics, Inc. | Lifting mechanism and chairs |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5163134A (en) * | 1974-01-21 | 1976-06-01 | Teijin Ltd | harobenzen no nitorokaho |
-
1987
- 1987-07-01 JP JP62162248A patent/JPH0794412B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS649960A (en) | 1989-01-13 |
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