JPH064558B2 - Method for producing methacrylic acid - Google Patents

Method for producing methacrylic acid

Info

Publication number
JPH064558B2
JPH064558B2 JP61002632A JP263286A JPH064558B2 JP H064558 B2 JPH064558 B2 JP H064558B2 JP 61002632 A JP61002632 A JP 61002632A JP 263286 A JP263286 A JP 263286A JP H064558 B2 JPH064558 B2 JP H064558B2
Authority
JP
Japan
Prior art keywords
methacrylic acid
catalyst
methacrolein
reaction
producing methacrylic
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
Application number
JP61002632A
Other languages
Japanese (ja)
Other versions
JPS62161739A (en
Inventor
求 大北
正明 加藤
雅夫 小林
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Rayon Co Ltd
Original Assignee
Mitsubishi Rayon Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Mitsubishi Rayon Co Ltd filed Critical Mitsubishi Rayon Co Ltd
Priority to JP61002632A priority Critical patent/JPH064558B2/en
Priority to DE8787900686T priority patent/DE3772655D1/en
Priority to PCT/JP1987/000008 priority patent/WO1987004086A1/en
Priority to US07/103,580 priority patent/US4803302A/en
Priority to KR1019870700810A priority patent/KR900002454B1/en
Priority to EP87900686A priority patent/EP0253896B1/en
Publication of JPS62161739A publication Critical patent/JPS62161739A/en
Publication of JPH064558B2 publication Critical patent/JPH064558B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00Technologies relating to chemical industry
    • Y02P20/50Improvements relating to the production of bulk chemicals
    • Y02P20/52Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts

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  • Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
  • Catalysts (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明はメタクロレインの気相接触酸化によりメタクロ
レインを製造する方法に関するものである。
TECHNICAL FIELD The present invention relates to a method for producing methacrolein by gas phase catalytic oxidation of methacrolein.

〔従来の技術〕[Conventional technology]

従来、不飽和アルデヒドを気相接触酸化して不飽和カル
ボン酸を製造する方法に関して、極めて数多くの特許が
提案されている。これらは主としてアクロレインからア
クリル酸を製造する方法を重点とするものであり、そこ
に提案されている触媒をメタクロレイン酸製造用として
使用すると副反応が大きいため選択率が低く、また寿命
が短かく実用的でなかつた。
Conventionally, an extremely large number of patents have been proposed regarding a method for producing an unsaturated carboxylic acid by vapor-phase catalytic oxidation of an unsaturated aldehyde. These mainly focus on the method of producing acrylic acid from acrolein, and when the catalyst proposed there is used for the production of methacrolein acid, the side reaction is large and the selectivity is low, and the life is short. It was not practical.

一方、メタクロレインからメタクリル酸を製造する方法
に関しても多数の触媒が提案されているが、いずれも、
反応成績が充分でなかつたり、触媒活性の経時低下が大
きかつたり、反応温度が高すぎたりの欠点を有し、工業
触媒としての使用に際しては更に改良が望まれている。
On the other hand, many catalysts have been proposed for the method of producing methacrylic acid from methacrolein, but all of them are
It has drawbacks such as insufficient reaction results, a large decrease in catalyst activity over time, and an excessively high reaction temperature, and further improvement is desired when it is used as an industrial catalyst.

〔発明が解決しようとする問題点〕[Problems to be solved by the invention]

本発明はメタクロレインからメタクリル酸を有利に製造
する方法の提供を目的とし、特に活性、選択性、寿命共
に実用性の高い触媒を用いたメタクリル酸の製造法を提
供しようとするものである。
An object of the present invention is to provide a method for producing methacrylic acid from methacrolein in an advantageous manner, and particularly to provide a method for producing methacrylic acid using a catalyst having high activity, selectivity and long life.

〔問題点を解決するための手段〕[Means for solving problems]

本発明はメタクロレインを分子状酸素で気相接触酸化し
メタクリル酸を製造するにあたり、 一般式 PaMobcFedCueSbfghij (ここで式中、Xはカリウム、ルビジウム、セシウム及
びタリウムからなる群より選ばれた少なくとも1種以上
の元素、Yはテルル、ランタン及びホウ素からなる群よ
り選ばれた少なくとも1種以上の元素、Zは銀及び/又
はマグネシウムを示し、aないしiは各元素の原子比率
を表わし、b=12のとき、a=0.3〜4、c=0.01〜
3、d=0.01〜4、e=0.01〜3、f=0.01〜3、g=
0.01〜3、h=0.001〜5、i=0〜5であり、jは前
記各成分の原子価を満足するのに必要な酸素原子数であ
る。)で表される触媒であって、かつ触媒構成成分がヘ
テロポリ酸塩構造である触媒を使用する事を特徴とする
メタクリル酸の製造法である。
In the present invention, when methacrolein is subjected to vapor-phase catalytic oxidation with molecular oxygen to produce methacrylic acid, a general formula P a Mo b V c F d Cu e Sb f X g Y h Z i O j (wherein X is at least one element selected from the group consisting of potassium, rubidium, cesium and thallium, Y is at least one element selected from the group consisting of tellurium, lanthanum and boron, Z is silver and / or Represents magnesium, a to i represent atomic ratios of respective elements, and when b = 12, a = 0.3 to 4, c = 0.01 to
3, d = 0.01 to 4, e = 0.01 to 3, f = 0.01 to 3, g =
0.01-3, h = 0.001-5, i = 0-5, and j is the number of oxygen atoms required to satisfy the valence of each component. The method for producing methacrylic acid is characterized in that the catalyst represented by the formula (1) is used, and the catalyst constituent component is a heteropolyacid salt structure.

本発明で用いる触媒は、これをX線回析でみた場合にヘ
テロポリ酸塩特有のピークである2θ=26.4゜,10.8゜に
大きなピークが現れ、ヘテロポリ酸に特有の2θ=8.0
゜,8.9゜,9.3゜には殆どピークがみられないので、実質
的に全部がヘテロポリ酸塩構造を有していると考えられ
る。ヘテロポリ酸塩構造の触媒は徐々に分解して触媒活
性が低下し、到底工業的に耐え得る程度の寿命を有しな
いという見解もみられるが、これは一部の触媒について
真実であってもすべてのヘテロポリ酸塩構造の触媒に当
てはまる事実ではない。
The catalyst used in the present invention has large peaks at 2θ = 26.4 ° and 10.8 °, which are peculiar to the heteropolyacid salt, when observed by X-ray diffraction, and 2θ = 8.0 peculiar to the heteropolyacid.
Since almost no peaks are observed at °, 8.9 °, and 9.3 °, it is considered that substantially all have a heteropolyacid salt structure. There is also a view that a catalyst having a heteropolyacid salt structure gradually decomposes and its catalytic activity decreases, and it does not have an industrially endurable lifetime. This is not the case for catalysts with a heteropolyacid salt structure.

本発明においては、リン、モリブデン、バナジウム及び
銅を含む触媒に特定量の鉄とアンチモン及びその他の特
定元素を加えることにより活性、選択性が高くなり、活
性が高いために低い反応温度でも充分な反応率を達成す
ることができ、その結果長期にわたつて高い触媒活性が
維持されるので工業的価値の極めて高いメタクリル酸の
製造法を提供できる。
In the present invention, by adding a specific amount of iron, antimony and other specific elements to a catalyst containing phosphorus, molybdenum, vanadium and copper, the activity and the selectivity are increased, and the activity is high, so that the reaction temperature is sufficient. A reaction rate can be achieved, and as a result, a high catalytic activity is maintained over a long period of time, so that a method for producing methacrylic acid having an extremely high industrial value can be provided.

本発明に用いられる触媒を製造する方法としては特殊な
方法に限定され必要はなく、成分の著しい偏在を伴わな
い限り、従来からよく知られている例えば蒸発乾固法、
沈澱法等の種々の方法を用いることができる。
The method for producing the catalyst used in the present invention is not limited to a special method, and unless a significant uneven distribution of the components is involved, a conventionally well-known method such as an evaporation-drying method,
Various methods such as a precipitation method can be used.

触媒の調製に用いる原料化合物としては各元素の硝酸
塩、炭酸塩、アンモニウム塩、ハロゲン化物、酸化物な
どを組合せて使用することができる。
As the raw material compound used for the preparation of the catalyst, nitrates, carbonates, ammonium salts, halides, oxides and the like of each element can be used in combination.

本発明の方法で用いる触媒は無担体でも有効であるが、
シリカ、アルミナ、シリカ・アルミナ、シリコンカーバ
イト等の不活性担体に担持させるか、あるいはこれで希
釈して用いることもできる。
Although the catalyst used in the method of the present invention is effective without a carrier,
It can also be used by supporting it on an inert carrier such as silica, alumina, silica-alumina, or silicon carbide, or by diluting it.

本発明の実施に際し、原料ガス中のメタクロレインの濃
度は広い範囲で変えることができるが、容量で1〜20
%が適当であり、特に3〜10%が好ましい。
In carrying out the present invention, the concentration of methacrolein in the raw material gas can be varied over a wide range, but the volume of methacrolein is 1 to 20
% Is suitable, and particularly preferably 3 to 10%.

原料メタクロレインは水、低級飽和アルデヒド等の不純
物を少量含んでいてもよく、これらの不純物は反応に実
質的は影響を与えない。
The raw material methacrolein may contain a small amount of impurities such as water and lower saturated aldehydes, and these impurities do not substantially affect the reaction.

酸素源としては空気を用いるのが経済的であるが、必要
ならば純酸素で富化した空気も用い得る。
It is economical to use air as the oxygen source, but pure oxygen-enriched air can be used if desired.

原料ガス中の酸素濃度はメタクロレインに対するモル比
で規定され、この値は0.3〜4、特に0.4〜2.5が好まし
い。
The oxygen concentration in the raw material gas is defined by the molar ratio with respect to methacrolein, and this value is preferably 0.3 to 4, particularly 0.4 to 2.5.

原料ガスは窒素、水蒸気、炭酸ガス等の不活性ガスを加
えて希釈してもよい。反応圧力は常圧から数気圧までが
よい。反応温度は230〜450℃の範囲で選ぶことが
できるが、特に250〜400℃が好ましい。反応は固
定床でも流動床でも行うことができる。
The raw material gas may be diluted by adding an inert gas such as nitrogen, steam or carbon dioxide gas. The reaction pressure is preferably atmospheric pressure to several atmospheres. The reaction temperature can be selected in the range of 230 to 450 ° C, but particularly preferably 250 to 400 ° C. The reaction can be carried out in a fixed bed or a fluidized bed.

〔実施例〕〔Example〕

以下、本発明による触媒の調製法および、それを用いて
の反応例を具体的に説明する。
Hereinafter, a method for preparing the catalyst according to the present invention and a reaction example using the same will be specifically described.

実施例、比較例中、部は重量部を意味し、分析はガスク
ロマトグラフイーにより行つた。また、メタクロレイン
の反応率、生成するメタクリル酸の選択率は以下のよう
に定義される。
In the examples and comparative examples, “part” means “part by weight”, and analysis was carried out by gas chromatography. In addition, the reaction rate of methacrolein and the selectivity of methacrylic acid produced are defined as follows.

実施例1 パラモリブデン酸アンモニウム100部、メタパナジン
酸アンモニウム2.8部及び硝酸カリウム4.8部を純水30
0部に溶解した。これに85%リン酸8.2部を純水10
部に溶解したものを加え、更にテルル酸3.3部を純水2
0部に溶解したもの及び三酸化アンチモン3.4を加え撹
拌しながら95℃に昇温した。
Example 1 100 parts of ammonium paramolybdate, 2.8 parts of ammonium metapanazinate and 4.8 parts of potassium nitrate were added to 30 parts of pure water.
Dissolved in 0 parts. To this, 8.2 parts of 85% phosphoric acid was added to pure water 10
Add the dissolved part to 3.3 parts of telluric acid and add 2 parts of pure water.
What was melt | dissolved in 0 part and 3.4 antimony trioxide were added, and it heated up at 95 degreeC, stirring.

つぎに、硝酸銅3.4部及び硝酸第二鉄5.7部を純水30部
に溶解したものを加え、混合液を100℃に加熱撹拌し
ながら蒸発乾固した。
Next, a solution prepared by dissolving 3.4 parts of copper nitrate and 5.7 parts of ferric nitrate in 30 parts of pure water was added, and the mixed solution was evaporated to dryness while heating and stirring at 100 ° C.

得られた固型物を130℃で16時間乾燥後加圧成型
し、空気流通下に380℃で5時間熱処理したものを触
媒として用いた。
The obtained solid product was dried at 130 ° C. for 16 hours, pressure-molded, and then heat-treated at 380 ° C. for 5 hours in an air stream to be used as a catalyst.

得られた触媒の酸素以外の元素の組成(以下同じ)はP
1.5Mo120.5Fe0.3Cu0.3Sb0.51Te0.3であ
つた。本触媒を反応器に充填し、メタクロレイン5%、
酸素10%、水蒸気30%、窒素55%(容量%)の混
合ガスを反応温度290℃、接触時間3.6秒で通じた。
生成物を捕集しガスクロマトグラフイーで分析したとこ
ろ、メタクロレイン反応率87.5%、メタクリル酸選択率
87.3%であつた。
The composition of elements other than oxygen in the obtained catalyst (the same applies hereinafter) is P
It was 1.5 Mo 12 V 0.5 Fe 0.3 Cu 0.3 Sb 0.5 K 1 Te 0.3 . The catalyst was packed in a reactor and methacrolein 5%,
A mixed gas of oxygen 10%, water vapor 30%, and nitrogen 55% (volume%) was passed at a reaction temperature of 290 ° C. and a contact time of 3.6 seconds.
When the product was collected and analyzed by gas chromatography, the reaction rate of methacrolein was 87.5% and the selectivity of methacrylic acid was high.
It was 87.3%.

同一条件で約1000時間反応を継続したところメタク
ロレイン反応率87.3%、メタクリル酸選択率87.0%であ
つた。
When the reaction was continued for about 1000 hours under the same conditions, the methacrolein conversion rate was 87.3% and the methacrylic acid selectivity was 87.0%.

実施例2 実施例1に準じてP1Mo121Fe0.2Cu0.1Sb1
10.3の組成の触媒を調製し、実施例1と同一条件で
反応したところ、メタクロレイン反応率86.5%、メタク
リル酸選択率87.9%であつた。
Example 2 P 1 Mo 12 V 1 Fe 0.2 Cu 0.1 Sb 1 C according to Example 1
When a catalyst having a composition of s 1 B 0.3 was prepared and reacted under the same conditions as in Example 1, the methacrolein conversion was 86.5% and the methacrylic acid selectivity was 87.9%.

実施例3〜6 実施例1に準じ、但しZ成分に相当する銀及びマグネシ
ウムの添加は硝酸銅及び硝酸第二鉄と一緒に純水に溶解
して行い、下記表の各触媒を調製し、実施例1と同一条
件で反応し次表の結果を得た。
Examples 3 to 6 According to Example 1, except that the addition of silver and magnesium corresponding to the Z component was carried out by dissolving in pure water together with copper nitrate and ferric nitrate to prepare each catalyst in the following table, The reaction was carried out under the same conditions as in Example 1, and the results shown in the following table were obtained.

実施例7 実施例1に準じてP1.7Mo120.7Fe0.4Cu0.1Sb
0.91La0.05の組成の触媒を調整し、実施例1と同一
条件で反応させた。反応結果はメタクロレイン反応率が
87.6%、メタクリル酸選択率87.0%であつた。
Example 7 P 1.7 Mo 12 V 0.7 Fe 0.4 Cu 0.1 Sb according to Example 1
A catalyst having a composition of 0.9 K 1 La 0.05 was prepared and reacted under the same conditions as in Example 1. The reaction result shows that the methacrolein reaction rate is
The selectivity was 87.6% and the methacrylic acid selectivity was 87.0%.

実施例8 実施例1の触媒を用い、反応温度を305℃に変えた以
外は、実施例1と同一条件で反応したところ、メタクロ
レイン反応率97.3%メタクリル酸選択率81.5%であつ
た。
Example 8 Using the catalyst of Example 1, the reaction was carried out under the same conditions as in Example 1 except that the reaction temperature was changed to 305 ° C., resulting in a methacrolein conversion of 97.3% and methacrylic acid selectivity of 81.5%.

実施例9 実施例2の触媒を用い、反応温度を305℃に変えた以
外は、実施例1と同一条件で反応したところ、メタクロ
レイン反応率が97.3%、メタクリル酸選択率81.2%であ
つた。
Example 9 The reaction was conducted under the same conditions as in Example 1 except that the reaction temperature was changed to 305 ° C. using the catalyst of Example 2, and the methacrolein conversion was 97.3% and the methacrylic acid selectivity was 81.2%. .

比較例1〜3 実施例1に準じて下記表の比較触媒を調製し、実施例1
と同一条件で反応し次の結果を得た。
Comparative Examples 1 to 3 Comparative catalysts shown in the following table were prepared according to Example 1, and Example 1
The following results were obtained by reacting under the same conditions as.

【図面の簡単な説明】[Brief description of drawings]

第1図は実施例1で得られた触媒のX線回析図である。 FIG. 1 is an X-ray diffraction diagram of the catalyst obtained in Example 1.

フロントページの続き (56)参考文献 特開 昭55−2619(JP,A) 特開 昭59−115750(JP,A)Continuation of front page (56) References JP-A-55-2619 (JP, A) JP-A-59-115750 (JP, A)

Claims (1)

【特許請求の範囲】[Claims] 【請求項1】メタクロレインを分子状酸素で気相接触酸
化しメタクリル酸を製造するにあたり、 一般式 PaMobcFedCueSbfghij (ここで式中、Xはカリウム、ルビジウム、セシウム及
びタリウムからなる群より選ばれた少なくとも1種以上
の元素、Yはテルル、ランタン及びホウ素からなる群よ
り選ばれた少なくとも1種以上の元素、Zは銀及び/又
はマグネシウムを示し、aないしは各元素の原子比率
を表し、b=12のとき、a=0.3〜4、c=0.01〜
3、d=0.01〜4、e=0.01〜3、f=0.01〜3、g=
0.01〜3、h=0.001〜5、=0〜5であり、jは前
記各成分の原子価を満足するのに必要な酸素原子数であ
る。)で表される触媒であって、かつ触媒構成成分がヘ
テロポリ酸塩構造である触媒を使用する事を特徴とする
メタクリル酸の製造法。
1. When producing methacrylic acid by vapor-phase catalytic oxidation of methacrolein with molecular oxygen, a compound represented by the general formula: P a Mo b V c Fe d Cu e Sb f X g Y h Z i O j Where X is at least one element selected from the group consisting of potassium, rubidium, cesium and thallium, Y is at least one element selected from the group consisting of tellurium, lanthanum and boron, Z is silver and / Or magnesium, a to i represents the atomic ratio of each element, when b = 12, a = 0.3 to 4, c = 0.01 to
3, d = 0.01 to 4, e = 0.01 to 3, f = 0.01 to 3, g =
0.01-3, h = 0.001-5, i = 0-5, and j is the number of oxygen atoms required to satisfy the valence of each component. A method for producing methacrylic acid, characterized in that the catalyst represented by the formula (4) is used, and the catalyst constituent component is a heteropolyacid salt structure.
JP61002632A 1986-01-08 1986-01-09 Method for producing methacrylic acid Expired - Lifetime JPH064558B2 (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
JP61002632A JPH064558B2 (en) 1986-01-09 1986-01-09 Method for producing methacrylic acid
DE8787900686T DE3772655D1 (en) 1986-01-08 1987-01-06 PRODUCTION OF METHACRYLIC ACID AND CATALYSTS THEREOF.
PCT/JP1987/000008 WO1987004086A1 (en) 1986-01-08 1987-01-06 Process for producing methacrylic acid and catalysts for the process
US07/103,580 US4803302A (en) 1986-01-08 1987-01-06 Process for the production of methacrylic acid
KR1019870700810A KR900002454B1 (en) 1986-01-08 1987-01-06 Process for producing methacrylic acid and catalysts for the process
EP87900686A EP0253896B1 (en) 1986-01-08 1987-01-06 Process for producing methacrylic acid and catalysts for the process

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP61002632A JPH064558B2 (en) 1986-01-09 1986-01-09 Method for producing methacrylic acid

Publications (2)

Publication Number Publication Date
JPS62161739A JPS62161739A (en) 1987-07-17
JPH064558B2 true JPH064558B2 (en) 1994-01-19

Family

ID=11534766

Family Applications (1)

Application Number Title Priority Date Filing Date
JP61002632A Expired - Lifetime JPH064558B2 (en) 1986-01-08 1986-01-09 Method for producing methacrylic acid

Country Status (1)

Country Link
JP (1) JPH064558B2 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102489321A (en) * 2011-12-28 2012-06-13 郑州大学 Preparation method of Ag/AgCl hybrid photocatalyst

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4056429B2 (en) 2003-06-05 2008-03-05 株式会社日本触媒 Method for producing (meth) acrylic acid

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS552619A (en) * 1978-06-21 1980-01-10 Nippon Kayaku Co Ltd Preparation of methacrylic acid and catalyst
JPS59115750A (en) * 1982-12-22 1984-07-04 Nippon Shokubai Kagaku Kogyo Co Ltd Catalyst for synthesis of methacrylic acid

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102489321A (en) * 2011-12-28 2012-06-13 郑州大学 Preparation method of Ag/AgCl hybrid photocatalyst

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