JP3218125B2 - Trioxane production method - Google Patents
Trioxane production methodInfo
- Publication number
- JP3218125B2 JP3218125B2 JP15918293A JP15918293A JP3218125B2 JP 3218125 B2 JP3218125 B2 JP 3218125B2 JP 15918293 A JP15918293 A JP 15918293A JP 15918293 A JP15918293 A JP 15918293A JP 3218125 B2 JP3218125 B2 JP 3218125B2
- Authority
- JP
- Japan
- Prior art keywords
- trioxane
- solid
- basic substance
- acid catalyst
- 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 - Fee Related
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
- Heterocyclic Compounds That Contain Two Or More Ring Oxygen Atoms (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は、ポリオキシメチレン樹
脂の原料等として用いられるトリオキサンを製造する方
法に関するものである。さらに詳しくは、ホルムアルデ
ヒド水溶液からトリオキサンを合成するにあたり、蟻酸
生成を抑えたトリオキサンの製造方法を提供するもので
ある。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing trioxane used as a raw material of a polyoxymethylene resin. More specifically, the present invention provides a method for producing trioxane, which suppresses formic acid generation when synthesizing trioxane from an aqueous formaldehyde solution.
【０００２】[0002]
【従来の技術及び発明が解決しようとする課題】従来、
トリオキサンを製造する方法としては、30〜70重量％の
ホルムアルデヒド水溶液を硫酸等の液状酸触媒の存在下
で加熱反応させ、蒸留してトリオキサン、ホルムアルデ
ヒドを含む水溶液として液状酸触媒を含む反応系から分
離した後、溶剤抽出等の方法でトリオキサンを分離精製
する方法が古くから知られている（例えば特公昭41−63
44号公報）。しかしながら、かかる方法においては、ホ
ルムアルデヒド水溶液からトリオキサンを合成するに際
し、副反応であるカニツァロ反応が起こり、蟻酸が生成
する。蟻酸はトリオキサンを重合してポリアセタール樹
脂を製造する場合の最も有害な不純物であり、又、他の
用途に対してもトリオキサンの分解を促進し望ましくな
い。従って、トリオキサンの合成時における蟻酸の発生
を抑制することは、精製等の後工程を簡略化し、良質の
トリオキサンを得る上で重要な課題である。一方、トリ
オキサンの合成において、硫酸等の液状酸触媒の代わり
に、或る種の強酸性陽イオン交換樹脂等の固体酸触媒を
用いることにより、硫酸等の液状酸を触媒として用いる
場合に比較して蟻酸生成量が減少する場合もあるが、尚
充分ではない。本発明は、トリオキサンの合成におい
て、トリオキサンの生成反応を何ら阻害することなく、
蟻酸の生成を抑制し、更には原料ホルムアルデヒドから
混入する蟻酸をも除去ないし減少して、その精製工程を
簡略化し、良質のトリオキサンを得ることを目的とする
ものである。2. Description of the Related Art
As a method for producing trioxane, a 30 to 70% by weight aqueous solution of formaldehyde is heated and reacted in the presence of a liquid acid catalyst such as sulfuric acid, and distilled to separate from a reaction system containing a liquid acid catalyst as an aqueous solution containing trioxane and formaldehyde. After that, a method of separating and purifying trioxane by a method such as solvent extraction has been known for a long time (for example, Japanese Patent Publication No. 41-63).
No. 44). However, in such a method, when synthesizing trioxane from an aqueous formaldehyde solution, a cannizaro reaction, which is a side reaction, occurs, and formic acid is generated. Formic acid is the most harmful impurity when polymerizing trioxane to produce a polyacetal resin, and also promotes the decomposition of trioxane for other uses, which is not desirable. Therefore, suppressing the generation of formic acid during the synthesis of trioxane is an important issue in simplifying the subsequent steps such as purification and obtaining good quality trioxane. On the other hand, in the synthesis of trioxane, a solid acid catalyst such as a certain strongly acidic cation exchange resin is used in place of a liquid acid catalyst such as sulfuric acid, so that a liquid acid such as sulfuric acid is used as a catalyst. In some cases, the amount of formic acid produced is reduced, but it is still not sufficient. The present invention, in the synthesis of trioxane, without any inhibition of the production reaction of trioxane,
An object of the present invention is to suppress the production of formic acid and further remove or reduce formic acid mixed in from the raw material formaldehyde to simplify the purification process and obtain good-quality trioxane.
【０００３】[0003]
【課題を解決するための手段】本発明者らは、トリオキ
サンの合成触媒として固体酸を使用し、これに特定の固
体塩基性物質を反応系に添加併用することにより、上記
目的が達成されることを見出し、本発明に到達した。即
ち本発明は、ホルムアルデヒド水溶液からトリオキサン
を合成するにあたり、有機質又は無機質の水不溶性の固
体酸触媒と共に、有機質又は無機質の水不溶性の固体塩
基性物質を反応系に存在せしめて合成反応を行うことを
特徴とするトリオキサンの製造法である。一般に、酸性
物質と塩基性物質の併用は、中和反応により夫々の特性
効果を相殺して、何れの効果をも消去してしまうのが一
般的であり、ホルムアルデヒド水溶液からトリオキサン
を合成する場合においても、塩基性物質の添加はトリオ
キサンの合成触媒としての酸触媒の活性を阻害し、トリ
オキサンの生成を妨害するものと考えられ、事実、水溶
性又は液体の塩基性物質の併用はトリオキサンの合成反
応を停止してしまう。又、酸触媒が硫酸の如き液体酸又
は水溶性酸触媒の場合には、併用する塩基性物質が水に
不溶性であってもその効果は相殺され、効果が発揮され
ない。しかし、本発明の如く、トリオキサン合成反応の
触媒として水不溶性の固体酸を使用し、且つ水不溶性の
固体塩基性物質を併用することにより、意外にも両者の
特性機能を相殺することなく、固体酸触媒はその活性を
保ってトリオキサンの生成を円滑に行うことができ、し
かも固体塩基性物質は蟻酸の生成を抑制するのみなら
ず、原料ホルムアルデヒドから持ち込まれる蟻酸をも低
減、除去する機能を有し、蟻酸の含量の著しく低減した
良質のトリオキサンを取得することができ、トリオキサ
ンの合成反応における斯かる特定の固体酸触媒と固体塩
基性物質との併用と、その効果はこれまで全く知られて
いなかった本発明の特徴である。The present inventors have achieved the above object by using a solid acid as a catalyst for synthesizing trioxane and adding a specific solid basic substance to the reaction system. The inventors have found that the present invention has been achieved. That is, in the present invention, in synthesizing trioxane from an aqueous formaldehyde solution, an organic or inorganic water-insoluble solid basic substance is present in a reaction system together with an organic or inorganic water-insoluble solid acid catalyst to perform a synthesis reaction. This is a method for producing a characteristic trioxane. In general, the combined use of an acidic substance and a basic substance generally offsets each characteristic effect by a neutralization reaction and eliminates any effect.In the case of synthesizing trioxane from an aqueous formaldehyde solution, However, addition of a basic substance is considered to inhibit the activity of an acid catalyst as a catalyst for synthesizing trioxane and hinder the production of trioxane. Will stop. When the acid catalyst is a liquid acid such as sulfuric acid or a water-soluble acid catalyst, even if the basic substance used together is insoluble in water, the effect is canceled and the effect is not exhibited. However, as in the present invention, a water-insoluble solid acid is used as a catalyst for the trioxane synthesis reaction, and by using a water-insoluble solid basic substance in combination, unexpectedly, the solid and solid functions are not canceled out. The acid catalyst maintains its activity and can smoothly produce trioxane, and the solid basic substance not only suppresses the production of formic acid, but also has the function of reducing and removing formic acid introduced from the raw formaldehyde. However, it is possible to obtain high-quality trioxane with significantly reduced formic acid content, and the combined use of such a specific solid acid catalyst and a solid basic substance in the synthesis reaction of trioxane, and the effects thereof have been completely known so far. There are no features of the present invention.
【０００４】本発明に使用する固体酸触媒としては、実
質的に水不溶性であれば有機質固体酸、無機質固体酸の
何れにてもよく、これらの２種以上の混合物又は複合物
でもよい。有機質固体酸としては、例えばスルホン酸
基、フルオロアルカンスルホン酸基等の如き酸性活性基
を有する各種の陽イオン交換樹脂が好ましく用いられ
る。これらの有機質固体酸の形状は特に限定するもので
はなく、粉粒状、繊維状、膜状等何れでもよく、又、他
の担体に被覆させて任意の形状として用いることができ
る。又、無機質固体酸としては、シリカ、アルミナ、チ
タニア等の酸化物、或いはシリカアルミナ、シリカチタ
ニア、アルミナボリア、ゼオライト、酸性白土等の無機
酸化物複合体が用いられ、水不溶性で酸活性を有するも
のであれば何れにてもよく、その形状も任意である。特
に無機質固体酸として好ましいのは、シリカアルミナ、
シリカチタニア、ゼオライト等である。又、これらの固
体酸はその表面が触媒活性を呈するものであるため、表
面積の大きな多孔質の固体であることが好ましい。又、
固体酸触媒は適当な方法で疎水化処理して用いれば更に
好適である。The solid acid catalyst used in the present invention may be any of an organic solid acid and an inorganic solid acid as long as it is substantially insoluble in water, and may be a mixture or a composite of two or more thereof. As the organic solid acid, various cation exchange resins having an acidic active group such as a sulfonic acid group and a fluoroalkanesulfonic acid group are preferably used. The shape of these organic solid acids is not particularly limited, and may be any of a granular form, a fibrous form, a film form, and the like, and may be used as an arbitrary form by coating with another carrier. As the inorganic solid acid, an oxide such as silica, alumina and titania, or an inorganic oxide complex such as silica alumina, silica titania, alumina boria, zeolite, and acid clay are used, which are water-insoluble and have acid activity. Any shape may be used as long as the shape is arbitrary. Particularly preferred as inorganic solid acids are silica alumina,
Silica titania, zeolite and the like. In addition, since these solid acids exhibit catalytic activity on their surfaces, they are preferably porous solids having a large surface area. or,
It is more preferable that the solid acid catalyst is used after being subjected to a hydrophobic treatment by an appropriate method.
【０００５】一方、本発明の方法において、上記固体酸
触媒と共に使用する固体塩基性物質は、これも実質的に
水不溶性であれば有機質固体塩基性物質、無機質固体塩
基性物質の何れにてもよく、これらの２種以上の混合物
又は複合物でもよい。有機質固体塩基性物質としては塩
基性陰イオン交換樹脂が例示される。塩基性陰イオン交
換樹脂としては、例えば４級アンモニウム基、１〜３級
のアミノ基等の塩基性活性基を有する陰イオン交換樹脂
等が挙げられ、これらはスチレン系樹脂等の如きビニル
系の高分子化合物として形成され、その重合法からゲル
型及びＭＲ型がある。これらの塩基性陰イオン交換樹脂
の種類は、トリオキサンの合成反応条件、例えばホルム
アルデヒド水溶液中のホルムアルデヒド濃度及び反応液
温度によって適宜選択される。一般にホルムアルデヒド
水溶液は、その濃度と温度の関係においてパラホルムが
発生し、その取扱い上支障を生じるため、比較的高濃度
のホルムアルデヒド水溶液を使用する場合は比較的高温
にする必要があり、このような場合、陰イオン交換樹脂
の耐熱性の点から１〜３級のアミノ基を活性基とする弱
塩基性陰イオン交換樹脂の使用が望ましい。又、無機質
固体塩基性物質としては、水不溶性のアルカリ土類金属
酸化物、アルカリ土類金属酸化物の混合物、アルカリ土
類金属酸化物をシリカやアルミナと複合化したものが例
示される。又、固体塩基性物質は必要に応じ適当な方法
で疎水化処理して用いれば更に好適である。[0005] On the other hand, in the method of the present invention, the solid basic substance used together with the solid acid catalyst may be any of an organic solid basic substance and an inorganic solid basic substance, if they are also substantially insoluble in water. It may be a mixture or a composite of two or more of these. Examples of the organic solid basic substance include a basic anion exchange resin. Examples of the basic anion exchange resin include, for example, anion exchange resins having a basic active group such as a quaternary ammonium group and a primary to tertiary amino group, and the like. These include vinyl-based resins such as styrene-based resins. It is formed as a polymer compound, and there are a gel type and an MR type depending on the polymerization method. The type of these basic anion exchange resins is appropriately selected depending on the reaction conditions for synthesizing trioxane, for example, the formaldehyde concentration in an aqueous formaldehyde solution and the temperature of the reaction solution. In general, formaldehyde aqueous solution generates paraform in relation to its concentration and temperature, which causes trouble in handling.When using a relatively high concentration of formaldehyde aqueous solution, it is necessary to raise the temperature to a relatively high level. From the viewpoint of the heat resistance of the anion exchange resin, it is desirable to use a weakly basic anion exchange resin having a primary or secondary amino group as an active group. Examples of the inorganic solid basic substance include a water-insoluble alkaline earth metal oxide, a mixture of alkaline earth metal oxides, and a composite of an alkaline earth metal oxide with silica or alumina. Further, it is more preferable that the solid basic substance is used after being subjected to a hydrophobizing treatment by an appropriate method if necessary.
【０００６】本発明における原料ホルムアルデヒドは、
一般には30〜85重量％のホルムアルデヒド水溶液が用い
られる。又、反応温度は80〜120 ℃である。一般に低
温、低ホルムアルデヒド濃度では長い反応時間を要し、
又、取得トリオキサンも低濃度となるため比較的高温で
高濃度のホルムアルデヒド溶液（例えば95〜110 ℃、ホ
ルムアルデヒド55〜75重量％）を用いるのが好ましい
が、高温に過ぎると固体酸触媒や固体塩基性物質の活性
低下を生じ好ましくない。尚、本発明において使用する
固体酸触媒と固体塩基性物質の使用割合は特に限定する
ものではなく、両者の夫々の機能を保持する時間（寿
命）や原料ホルムアルデヒド中の蟻酸含有量により適宜
決定すればよいが、一般には固体酸触媒１重量部に対し
固体塩基性物質0.1 〜10重量部である。In the present invention, the starting formaldehyde is
Generally, a 30 to 85% by weight aqueous formaldehyde solution is used. The reaction temperature is 80 to 120 ° C. Generally, long reaction time is required at low temperature and low formaldehyde concentration,
Since the obtained trioxane also has a low concentration, it is preferable to use a formaldehyde solution having a relatively high temperature and a high concentration (for example, 95 to 110 ° C., 55 to 75% by weight of formaldehyde). It is not preferable because the activity of the active substance is reduced. The proportions of the solid acid catalyst and the solid basic substance used in the present invention are not particularly limited, and may be determined as appropriate according to the time (life) during which the respective functions are maintained and the formic acid content in the raw formaldehyde. The amount is generally 0.1 to 10 parts by weight of the solid basic substance per 1 part by weight of the solid acid catalyst.
【０００７】本発明のトリオキサン合成反応における上
記固体酸触媒及び固体塩基性物質の使用形態は、固定床
形式、流動混合形式の何れにてもよく、この両者が夫々
自由に流動し混合した状態であっても夫々の機能を発揮
し本発明の目的、効果は達せられるが、この両者は夫々
異なる機能を利用するものであり、一般には夫々の更新
時期、再生方法等も異なるため、同一反応器（系）内に
分離して存在させた方が好都合の場合が多く、その意味
から両者は固定床型式、又はそれに準じた方法で分離し
た状態で使用するのが好ましい。又、反応装置として
は、充填層型、パイプ管型、かご型、流動層型、段塔型
など何れの形式でもよい。又、トリオキサンの合成反応
と、生成トリオキサンの濃縮分離を連続的に行うため、
反応器と蒸留装置又は抽出装置を組み合わせ、反応器内
又は蒸留塔内等に本発明の固体酸触媒及び固体塩基性物
質を設置、又は含有させて連続的にトリオキサンの合
成、濃縮分離を行うことも好ましい方法の一つである。The use of the solid acid catalyst and the solid basic substance in the trioxane synthesis reaction of the present invention may be either a fixed-bed type or a fluid-mixing type, in which both are freely flowing and mixed. Even if they do, the respective functions are exhibited and the object and effects of the present invention can be achieved, but both use different functions, and in general, their renewal time, regeneration method, etc. are also different. In many cases, it is more convenient to separate them in (system), and in that sense, it is preferable to use both in a fixed bed type or in a state of being separated by a method similar thereto. The reactor may be of any type such as a packed bed type, a pipe tube type, a cage type, a fluidized bed type, and a column type. In addition, to continuously perform the trioxane synthesis reaction and the concentration and separation of the produced trioxane,
Combining a reactor and a distillation apparatus or an extraction apparatus, and installing or containing the solid acid catalyst and the solid basic substance of the present invention in a reactor or a distillation column to continuously synthesize, concentrate, and separate trioxane. Is also one of the preferred methods.
【０００８】[0008]
【実施例】以下、実施例をもって本発明を具体的に説明
するが、本発明はこれらによって限定されるものではな
い。 実施例１〜４、比較例１〜５ 反応器に、表１に示す固体酸触媒及び固体塩基性物質を
充填し、60重量％のホルムアルデヒド水溶液（蟻酸濃度
1500ppm）を加え、95℃で攪拌し、トリオキサンの合成
を試みた。30分後に反応液を分析し、蟻酸及びトリオキ
サンの濃度を測定した。又、比較のため固体塩基性物質
を使用しない場合、及び触媒として硫酸（３％）を使用
した場合についても同様にして合成反応を行った。結果
を併せて表１に示す。尚、実施例で使用した固体酸触媒
及び固体塩基性物質は以下の通りである。 固体酸触媒 Ａ−１；スルホン酸型陽イオン交換樹脂（三菱化成
（株）、ダイヤイオンPK−216) Ａ−２；ゼオライトZSM-5 （水沢化学（株）) Ａ−３；フッ素化スルホン酸型陽イオン交換樹脂（デュ
ポン社、ナフィオンNR50) 固体塩基性物質 Ｂ−１；塩基性陰イオン交換樹脂（三菱化成（株）、ダ
イヤイオンWA−30) Ｂ−２；MgO-Al2O3 （複合体、モル比20−80）EXAMPLES The present invention will now be described specifically with reference to examples, but the present invention is not limited to these examples. Examples 1 to 4 and Comparative Examples 1 to 5 A reactor was charged with a solid acid catalyst and a solid basic substance shown in Table 1, and a 60% by weight aqueous solution of formaldehyde (formic acid concentration) was added.
(1500 ppm), and the mixture was stirred at 95 ° C. to try to synthesize trioxane. After 30 minutes, the reaction solution was analyzed, and the concentrations of formic acid and trioxane were measured. For comparison, a synthesis reaction was performed in the same manner when no solid basic substance was used and when sulfuric acid (3%) was used as a catalyst. The results are shown in Table 1. The solid acid catalyst and solid basic substance used in the examples are as follows. Solid acid catalyst A-1; Sulfonic acid type cation exchange resin (Mitsubishi Kasei Co., Ltd., Diaion PK-216) A-2; Zeolite ZSM-5 (Mizusawa Chemical Co., Ltd.) A-3; Fluorinated sulfonic acid Type cation exchange resin (Dupont, Nafion NR50) Solid basic substance B-1; Basic anion exchange resin (Mitsubishi Kasei Co., Ltd., Diaion WA-30) B-2; MgO-Al 2 O 3 ( Complex, molar ratio 20-80)
【０００９】[0009]
【表１】 [Table 1]
【００１０】実施例５〜８、比較例６〜10 前記実施例及び比較例に準じ、65重量％のホルムアルデ
ヒド水溶液（蟻酸濃度800ppm）を使用し、反応温度100
℃で同様にトリオキサンの合成を試み、30分後に反応液
を分析し、蟻酸及びトリオキサンの濃度を測定した。結
果を併せて表２に示す。Examples 5 to 8 and Comparative Examples 6 to 10 According to the above Examples and Comparative Examples, a 65% by weight aqueous solution of formaldehyde (800 ppm formic acid) was used, and a reaction temperature of 100%.
The synthesis of trioxane was attempted in the same manner at ° C, and after 30 minutes, the reaction solution was analyzed, and the concentrations of formic acid and trioxane were measured. The results are shown in Table 2.
【００１１】[0011]
【表２】 [Table 2]
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.7，ＤＢ名) C07D 323/06 B01J 29/04 B01J 31/08 B01J 31/10 ──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. 7 , DB name) C07D 323/06 B01J 29/04 B01J 31/08 B01J 31/10
Claims (4)
ンを合成するにあたり、有機質又は無機質の水不溶性の
固体酸触媒と共に、有機質又は無機質の水不溶性の固体
塩基性物質を反応系に存在せしめて合成反応を行うこと
を特徴とするトリオキサンの製造法。When synthesizing trioxane from an aqueous formaldehyde solution, an organic or inorganic water-insoluble solid basic substance is present in a reaction system together with an organic or inorganic water-insoluble solid acid catalyst to perform a synthesis reaction. Characteristic method for producing trioxane.
求項１記載のトリオキサンの製造法。2. The process for producing trioxane according to claim 1, wherein the solid acid catalyst is a cation exchange resin.
求項１記載のトリオキサンの製造法。3. The method for producing trioxane according to claim 1, wherein the solid acid catalyst is a metal oxide complex.
る請求項１〜３の何れか１項記載のトリオキサンの製造
法。4. The process for producing trioxane according to claim 1, wherein the solid basic substance is an anion exchange resin.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15918293A JP3218125B2 (en) | 1993-06-29 | 1993-06-29 | Trioxane production method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15918293A JP3218125B2 (en) | 1993-06-29 | 1993-06-29 | Trioxane production method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0717969A JPH0717969A (en) | 1995-01-20 |
| JP3218125B2 true JP3218125B2 (en) | 2001-10-15 |
Family
ID=15688105
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP15918293A Expired - Fee Related JP3218125B2 (en) | 1993-06-29 | 1993-06-29 | Trioxane production method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3218125B2 (en) |
-
1993
- 1993-06-29 JP JP15918293A patent/JP3218125B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0717969A (en) | 1995-01-20 |
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