JPS5842176B2 - Fuhouwa Carbon Sanno Seizouhou - Google Patents
Fuhouwa Carbon Sanno SeizouhouInfo
- Publication number
- JPS5842176B2 JPS5842176B2 JP50040659A JP4065975A JPS5842176B2 JP S5842176 B2 JPS5842176 B2 JP S5842176B2 JP 50040659 A JP50040659 A JP 50040659A JP 4065975 A JP4065975 A JP 4065975A JP S5842176 B2 JPS5842176 B2 JP S5842176B2
- Authority
- JP
- Japan
- Prior art keywords
- catalyst
- reaction
- nitrate
- carbon
- seizouhou
- 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
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
- 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】
本発明は不飽和アルデヒドを空気または分子状酸素によ
り、気相高温で酸化して相当する不飽和カルボン酸を製
造する方法に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a process for producing the corresponding unsaturated carboxylic acid by oxidizing an unsaturated aldehyde with air or molecular oxygen at high temperature in the gas phase.
従来、不飽和アルデヒドを気相接触酸化して相当する不
飽和カルボン酸の製造法に関して数多くの特許が提案さ
れている。Conventionally, many patents have been proposed regarding methods for producing corresponding unsaturated carboxylic acids by vapor phase catalytic oxidation of unsaturated aldehydes.
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
タクリル酸製造用として使用すると副反応が太きいため
選択率が低く、また、寿命が短かく実用的でなかった。The main focus is on the method of producing acrylic acid from acrolein, and when the catalyst proposed there is used for producing methacrylic acid, the selectivity is low due to large side reactions, and the life is short, making it impractical for practical use. It wasn't on point.
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
ても数多くの提案がなされており、例えばPMoSb系
(特開昭49−82622.85017゜109316
号など)、PMoアルカリ系(特開昭48−61416
.61417,67216゜72116号など)、PM
oAs系(特公昭49−10652号など)の触媒が知
られている。Many proposals have been made regarding methods for producing methacrylic acid from methacrolein.
etc.), PMo alkaline system (JP-A-48-61416)
.. 61417, 67216゜72116 etc.), PM
OAs-based catalysts (Japanese Patent Publication No. 49-10652, etc.) are known.
これらの触媒はそれぞれ特徴を有するものであるが反応
成績が低かったり、触媒活性の経時的低下が著しかった
り、反応温度が高すぎるなどの欠点も有し、工業触媒と
しては必ずしも充分とは言えない。Although each of these catalysts has its own characteristics, they also have drawbacks such as poor reaction results, a marked decline in catalytic activity over time, and too high reaction temperatures, so they cannot necessarily be said to be sufficient as industrial catalysts. .
本発明者らはメタクロレインからメタクリル酸を製造す
るに用いる触媒について鋭意研究したところ、上記の欠
点を改良し、活性、選択性、寿命ともに実用性の高い触
媒を見い出し、さらに、この触媒がアクロレインからア
クリル酸を製造する方法にも適用し得ることを見い出し
、本発明を完成するに到った。The present inventors conducted intensive research on catalysts used to produce methacrylic acid from methacrolein, and found a catalyst that improved the above-mentioned drawbacks and had high practicality in terms of activity, selectivity, and lifespan. The present inventors have discovered that the present invention can also be applied to a method for producing acrylic acid from acrylic acid, and have completed the present invention.
本発明は不飽和アルデヒドを分子状酸素で接触酸化して
相当する不飽和カルボン酸を得るに際し、一般式
P a M o b X c Y d Z e Of但
し、Pはリン、MOはモリブデン、Oは酸素を表わし、
さらにXはカリウム、ルビジウムおよびセシウムより成
る群から選ばれる少くとも一種、Yは鉄、ニッケルおよ
びウランより成る群から選ばれる少くとも一種、Zはタ
ングステン、亜鉛、カドミウム、コバルトおよびアンチ
モンより成る群から選ばれる少くとも一種、a t b
+ C+ d +e y fは各々の成分の原子比を
表わし、a=0.5〜6 + b= 12 t c=0
.2〜6 y d=0.01〜6+e−0〜6.fは触
媒の酸化状態で定まる値である。In the present invention, when an unsaturated aldehyde is catalytically oxidized with molecular oxygen to obtain a corresponding unsaturated carboxylic acid, the general formula P a Mo b X c Y d Z e Of, where P is phosphorus, MO is molybdenum, O represents oxygen;
Further, X is at least one selected from the group consisting of potassium, rubidium, and cesium, Y is at least one selected from the group consisting of iron, nickel, and uranium, and Z is at least one selected from the group consisting of tungsten, zinc, cadmium, cobalt, and antimony. At least one selected one, a t b
+ C+ d + e y f represents the atomic ratio of each component, a=0.5~6 + b= 12 t c=0
.. 2-6 y d=0.01-6+e-0-6. f is a value determined by the oxidation state of the catalyst.
で表わされる触媒を用いる製造法である。This is a production method using a catalyst represented by
本発明の方法によれば不飽和アルデヒドから不飽和カル
ボン酸が高収率、高選択率で得ることが可能であり、特
に長期にわたって高い触媒活性が維持されるので、工業
的価値はきわめて大きい。According to the method of the present invention, it is possible to obtain an unsaturated carboxylic acid from an unsaturated aldehyde in high yield and high selectivity, and in particular, high catalytic activity is maintained over a long period of time, so the industrial value is extremely large.
リンおよびモリブデンを含む触媒系がアクロレインまた
はメタクロレインの気相接触酸化用として有効であるこ
とは良く知られている。It is well known that catalyst systems containing phosphorus and molybdenum are effective for the gas phase catalytic oxidation of acrolein or methacrolein.
リンとモリブデンはその混合割合、熱処理の温度雰囲気
によってきわめて複雑な化合物を生成する。Phosphorus and molybdenum form extremely complex compounds depending on their mixing ratio and the temperature and atmosphere of heat treatment.
そのため、リン、モリブデンを含む触媒系を気相酸化に
用いると通常用いられる反応温度領域で経時的に活性、
選択性の低下が生ずることが多い。Therefore, when a catalyst system containing phosphorus and molybdenum is used for gas phase oxidation, it becomes active over time in the reaction temperature range normally used.
A decrease in selectivity often occurs.
本発明者らが先に提案(特願昭48−91976号)し
たリン、モリブデンおよびヒ素を含む触媒は活性、選択
性が高く、高性能であるが触媒の熱的安定性が低い欠点
を有している。The catalyst containing phosphorus, molybdenum, and arsenic that the present inventors proposed earlier (Japanese Patent Application No. 48-91976) has high activity, high selectivity, and high performance, but has the drawback of low thermal stability of the catalyst. are doing.
これに対してヒ素を全く含まない本発明の触媒では熱的
安定性が著しく高く、600°Cで熱処理を施しても高
性能を維持することができる。In contrast, the catalyst of the present invention, which does not contain any arsenic, has extremely high thermal stability and can maintain high performance even when heat treated at 600°C.
本発明の触媒ではリン、モリブデン以外の添加金属はリ
ン、モリブデンときわめて安定な塩を作る性質があり、
この事が活性、選択性の維持に寄与しているものと思わ
れる。In the catalyst of the present invention, added metals other than phosphorus and molybdenum have the property of forming extremely stable salts with phosphorus and molybdenum.
This seems to contribute to maintaining activity and selectivity.
本発明で用いる触媒の各成分元素の化学的な存在状態は
極めて複雑であって厳密には明らかでないが、おそらく
どの成分も単独の酸化物としては存在せず、緊密に結合
していると思われる。The chemical state of existence of each component element of the catalyst used in the present invention is extremely complex and is not strictly clear, but it is likely that none of the components exists as an individual oxide, but rather is tightly bound. It will be done.
触媒を調製する方法としては特殊な方法に限定する必要
はなく、成分の著しい偏在を伴なわない限り、従来から
よく知られている蒸発乾固法、沈澱法、酸化物混合法等
の種々の方法を用いることができる。The method for preparing the catalyst does not need to be limited to a special method, and various well-known methods such as evaporation to dryness method, precipitation method, oxide mixing method, etc. can be used as long as the method does not involve significant uneven distribution of components. A 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、アンモニウム塩、ハロゲン化物等の塩類、酸化物あ
るいはリン、モリブデン酸等のへテロポリ酸またはその
塩類を組合せて使用することができる。As the raw material compounds used in the preparation of the catalyst, salts and oxides of each element such as nitrates, ammonium salts, and halides, or heteropolyacids such as phosphorus and molybdic acid, or their salts can be used in combination.
例えばモリブデン酸アンモニウムの水溶液にリン酸の水
溶液を加えた後硝酸タリウム水溶液を加え、更に硝酸鉄
の水溶液を加えて得られたスラリーに適当な担体物質を
加えて蒸発乾固する。For example, an aqueous solution of phosphoric acid is added to an aqueous solution of ammonium molybdate, an aqueous solution of thallium nitrate is added, and an aqueous solution of iron nitrate is further added to the resulting slurry, an appropriate carrier material is added, and the slurry is evaporated to dryness.
熱処理の温度は300〜650℃、好ましくは350〜
6000Cの範囲で、熱処理の時間は温度によって異な
るが1時間ないし数十時間が適当である。The temperature of heat treatment is 300-650°C, preferably 350-650°C
The heat treatment time is within the range of 6000C and varies depending on the temperature, but is suitable for one hour to several tens of hours.
本発明の方法で用いる触媒はシリカ、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、あるいはこれらで希釈して用いることができ
る。The catalyst used in the method of the present invention can be supported on an inert carrier such as silica, alumina, silica-alumina, silicon carbide, etc., or can be used after being diluted with these.
本発明の触媒は固定床、流動床あるいは移動床にも使用
できる。The catalyst of the invention can be used in fixed beds, fluidized beds or moving beds.
原料ガス中の不飽和アルデヒド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、と
くに3〜15%が好ましい。Although the concentration of unsaturated aldehyde in the raw material gas can be varied within a wide range, a range of 1 to 20% by volume is appropriate, and a range of 3 to 15% is particularly preferred.
原料不飽和アルデヒドは水、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
実質的な影響を与えない。The raw material unsaturated aldehyde may contain small amounts of impurities such as water and lower saturated aldehydes, but 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 air enriched with pure oxygen can also be used if necessary.
原料ガス中の酸素濃度は不飽和アルデヒドに対するモル
比で規定され、この値は0.3〜4、とくに0.4〜2
.5が好ましい。The oxygen concentration in the raw material gas is defined by the molar ratio to the unsaturated aldehyde, and this value is 0.3 to 4, particularly 0.4 to 2.
.. 5 is preferred.
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。The raw material gas may be diluted by adding an inert gas such as nitrogen, water vapor, or carbon dioxide gas.
反応圧力は常圧から散気圧までがよい。The reaction pressure is preferably from normal pressure to diffused pressure.
反応温度は240〜450℃の範囲で選ぶことができる
が、とくに270〜400°Cが好ましい。Although the reaction temperature can be selected within the range of 240 to 450°C, 270 to 400°C is particularly preferred.
以下に実施例および比較例を挙げて本発明の方法を更に
詳しく説明する。The method of the present invention will be explained in more detail below with reference to Examples and Comparative Examples.
以下においては部は重量部を表わし、不飽和カルボン酸
選択率は不飽和アルデヒドの反応したモル数に対する生
成した不飽和カルボン酸のモル数の割合(パーセント)
を表わす。In the following, parts represent parts by weight, and unsaturated carboxylic acid selectivity is the ratio (percentage) of the number of moles of unsaturated carboxylic acid produced to the number of moles of unsaturated aldehyde reacted.
represents.
反応時間は反応条件に設定した時点から計った経過時間
を意味する。Reaction time means the elapsed time measured from the time when the reaction conditions were set.
実施例 1
パラモリブデン酸アンモニウム88.3gを約60℃の
純水400部に溶解した水溶液に85%リン酸9.7部
を純水10i5に溶解した水溶液を加えた。Example 1 To an aqueous solution in which 88.3 g of ammonium paramolybdate was dissolved in 400 parts of pure water at about 60° C., an aqueous solution in which 9.7 parts of 85% phosphoric acid was dissolved in 10 parts of pure water was added.
更にこの液に硝酸セシウム16.4部を純水200部に
溶解した溶液と硝酸第二鉄16.8部を純水50部に溶
解した水溶液を加えた後、攪拌しながら蒸発乾固した。Furthermore, a solution of 16.4 parts of cesium nitrate dissolved in 200 parts of pure water and an aqueous solution of 16.8 parts of ferric nitrate dissolved in 50 parts of pure water were added to this solution, and the mixture was evaporated to dryness while stirring.
得られたケークを130°で16時間乾燥した後、粉砕
した。The resulting cake was dried at 130° for 16 hours and then ground.
これを加圧成形し、10〜20メツシユに破砕したのち
、450℃で5時間焼成し、これを触媒とした。This was pressure-molded, crushed into 10 to 20 meshes, and then calcined at 450°C for 5 hours to be used as a catalyst.
この触媒の組成は原子比でP2Mo12 C52Fel
であった。The composition of this catalyst is P2Mo12C52Fel in atomic ratio.
Met.
本触媒を反応器に充填し、メタクロレイン5%、酸素1
0%、水蒸気30φ、窒素55%(容量%)の混合ガス
を反応温度335°C1接触時間3.6秒で通じた。This catalyst was packed into a reactor, and 5% methacrolein and 1% oxygen were added.
A mixed gas of 0% water vapor, 30φ water vapor, and 55% nitrogen (volume %) was passed through the reactor at a reaction temperature of 335° C. and a contact time of 3.6 seconds.
生成物をガスクロマトグラフ法によって分析したところ
、次のような結果を得た。When the product was analyzed by gas chromatography, the following results were obtained.
メタクロレイン反応率 78.6% *メタク
リル酸選択率 81,2φ
この他、酢酸、炭酸ガス、−酸化炭素等が生成した。Methacrolein reaction rate 78.6% *Methacrylic acid selectivity 81.2φ In addition, acetic acid, carbon dioxide gas, -carbon oxide, etc. were produced.
同一条件で約1000時間連続反応を行なった後、次の
結果を得た。After continuous reaction for about 1000 hours under the same conditions, the following results were obtained.
メタクロレイン反応率 78.6%
メタクリル酸選択率 81.3%
実施例 2〜4
実施例1と同様にしてX成分として硝酸セシウムあるい
は硝酸ルビジウムを用い、さらにY成分として硝酸第二
鉄の代りに硝酸ニッケル、硝酸ウラニルを用い、その他
の点については実施例1と同様にして触媒を調製した。Methacrolein reaction rate 78.6% Methacrylic acid selectivity 81.3% Examples 2 to 4 In the same manner as in Example 1, cesium nitrate or rubidium nitrate was used as the X component, and ferric nitrate was substituted for the Y component. A catalyst was prepared in the same manner as in Example 1 except that nickel nitrate and uranyl nitrate were used.
但し、焼成温度、開開は第1表に示した如く変えた。However, the firing temperature and opening were changed as shown in Table 1.
これらの触媒について反応温度以外は実施例1と同一に
して反応した。These catalysts were reacted in the same manner as in Example 1 except for the reaction temperature.
触媒、反応条件ならびに反応結果の要点を第1表に示す
。Table 1 summarizes the catalyst, reaction conditions, and reaction results.
実施例 10〜11
実施例1,6の触媒を用い、アクロレイン5%、酸素1
0%、水蒸気30%、窒素55多の混合ガ*スを接触時
間3.6秒で反応させた。Examples 10 to 11 Using the catalysts of Examples 1 and 6, 5% acrolein and 1% oxygen
A mixed gas containing 0% water vapor, 30% water vapor, and 55% nitrogen was reacted for a contact time of 3.6 seconds.
触媒、反応条件ならびに反応結果の要点を第3表に示す
。Table 3 summarizes the catalyst, reaction conditions, and reaction results.
実施例 12
実施例1の硝酸セシウムを硝酸カリウムに替え、硝酸第
二鉄を硝酸ニッケル及び硝酸コバルトに替えて、その他
の点については実施例1と同様にした。Example 12 The same procedure as in Example 1 was carried out except that cesium nitrate in Example 1 was replaced with potassium nitrate, and ferric nitrate was replaced with nickel nitrate and cobalt nitrate.
但し、組成比、焼成温度、時間は第4表に示した如く変
えた。However, the composition ratio, firing temperature, and time were changed as shown in Table 4.
この触媒について反応温度以外の条件は実施例1と同一
にして反応した。The reaction of this catalyst was carried out under the same conditions as in Example 1 except for the reaction temperature.
触媒ならびに反応結果の要点を第4表に示す。Table 4 shows the catalyst and the main points of the reaction results.
比較例 1〜3
実施例2において硝酸セシウムを、実施例4において硝
酸ニッケル、実施例2において硝酸ニッケルを除いた触
媒を調製し、反応温度以外は実施例1と同じにして反応
した。Comparative Examples 1 to 3 Catalysts were prepared except for using cesium nitrate in Example 2, nickel nitrate in Example 4, and nickel nitrate in Example 2, and the reactions were carried out in the same manner as in Example 1 except for the reaction temperature.
反応の結果を第4表に示す。The results of the reaction are shown in Table 4.
Claims (1)
する不飽和カルボン酸を得るに際し、次の一般式 %式% 但し、Pはリン、MOはモリブデン、Oは酸素を表わし
、Xはカリウム、ルビジウムおよびセシウムより成る群
から選ばれる少くとも一種、Yは鉄、ニッケルおよびウ
ランより戒る群から選ばれる少くとも一種、Zはタング
ステン、亜鉛、カドミウム、コバルトおよびアンチモン
より成る群から選ばれる少くとも一種、a、b、c、d
、e。 fは各々の成分の原子比を表わし、a=0.5〜6゜b
= 12 p c=0.2〜6 t d=0.01〜6
t eO〜6.fは触媒の酸化状態で定まる値である
。 で表わされる触媒を用いる製造法。[Claims] 1. When an unsaturated aldehyde is catalytically oxidized with molecular oxygen to obtain a corresponding unsaturated carboxylic acid, the following general formula % is used. However, P is phosphorus, MO is molybdenum, and O is oxygen. represented by At least one selected from the group, a, b, c, d
, e. f represents the atomic ratio of each component, a=0.5~6゜b
= 12 p c = 0.2 ~ 6 t d = 0.01 ~ 6
teO~6. f is a value determined by the oxidation state of the catalyst. A manufacturing method using a catalyst represented by
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP50040659A JPS5842176B2 (en) | 1975-04-03 | 1975-04-03 | Fuhouwa Carbon Sanno Seizouhou |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP50040659A JPS5842176B2 (en) | 1975-04-03 | 1975-04-03 | Fuhouwa Carbon Sanno Seizouhou |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS51115413A JPS51115413A (en) | 1976-10-12 |
JPS5842176B2 true JPS5842176B2 (en) | 1983-09-17 |
Family
ID=12586652
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP50040659A Expired JPS5842176B2 (en) | 1975-04-03 | 1975-04-03 | Fuhouwa Carbon Sanno Seizouhou |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS5842176B2 (en) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5248618A (en) * | 1975-10-14 | 1977-04-18 | Asahi Glass Co Ltd | Process for preparation of unsaturated carboxylic acids |
DE2718399A1 (en) * | 1976-05-05 | 1977-11-17 | Standard Oil Co Ohio | PROCESS FOR MANUFACTURING UNSATATURATED ALIPHATIC ACIDS AND CATALYSTS USED THEREFORE |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5333569A (en) * | 1976-09-09 | 1978-03-29 | Sony Corp | Method of reducing lattice defects of single crystal |
JPS5335924A (en) * | 1976-09-16 | 1978-04-03 | Hitachi Ltd | Current transformer |
JPS5341653A (en) * | 1976-09-27 | 1978-04-15 | Kubota Ltd | Forced air-cooled engine |
-
1975
- 1975-04-03 JP JP50040659A patent/JPS5842176B2/en not_active Expired
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5333569A (en) * | 1976-09-09 | 1978-03-29 | Sony Corp | Method of reducing lattice defects of single crystal |
JPS5335924A (en) * | 1976-09-16 | 1978-04-03 | Hitachi Ltd | Current transformer |
JPS5341653A (en) * | 1976-09-27 | 1978-04-15 | Kubota Ltd | Forced air-cooled engine |
Also Published As
Publication number | Publication date |
---|---|
JPS51115413A (en) | 1976-10-12 |
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