JPS6272634A - Purification of styrene compound - Google Patents

Abstract

PURPOSE:To remove the highly unsaturated impurities in a styrene compound in high selectivity easily, by selectively hydrogenating the impurities in the presence of a catalyst while keeping the partial pressure of hydrogen supplied to the reaction system at a specific level. CONSTITUTION:Highly unsaturated impurities (e.g. acetylene compound such as phenylacetylene, diolefins, etc.) in a styrene compound are selectively hydrogenated in the presence of a hydrogenation catalyst to eliminate the above impurities from the styrene compound. In the above process, the partial pressure of hydrogen supplied to the reaction system is maintained to <=2kg/cm<2>, preferably <=1kg/cm<2>. The hydrogenation selectivity of the impurities can be improved, the loss of the useful component such as styrene can be suppressed, the removing ratio of the impurities can be improved and a purified styrene compound having uniform polymerization characteristics and suitable for the production of a polymer having stable quality can be economically produced on an industrial scale by this process.

Description

【発明の詳細な説明】 （＆）発明の目的 本発明はスチレン類の精製方法、特に含有される高不飽
和不純物を容易に除去・（か製する方法に関する。DETAILED DESCRIPTION OF THE INVENTION (&) OBJECTS OF THE INVENTION The present invention relates to a method for purifying styrenes, and particularly to a method for easily removing and/or producing highly unsaturated impurities contained therein.

（産業上の利用分野） 本発明の精製方法は、スチレン類に含まれる高不飽和不
純物、すなわちフェニルアセチレン等のアセチレン類及
びジオレフィン類を高い選択率で選択的に水素添加して
容易に除去できるので、重合特性にバラツキがなく１品
質の安定したポリマー製品を得るのに適する精製スチレ
ン類を製造するのに有利に使用される。(Industrial Application Field) The purification method of the present invention easily removes highly unsaturated impurities contained in styrenes, that is, acetylenes such as phenylacetylene and diolefins by selectively hydrogenating them with high selectivity. Therefore, it is advantageously used to produce purified styrenes that are suitable for obtaining stable polymer products of one quality without variations in polymerization properties.

（従来の技術） スチレン類はポリマー原料として広く用いられている。(Conventional technology) Styrenes are widely used as polymer raw materials.

しかし、スチレン類を重合させてポリマー原料造する場
合に、重合特性にノ々ラツキがあり、安定した品質のポ
リマー製品が得られない問題点があった。However, when producing polymer raw materials by polymerizing styrenes, there was a problem that the polymerization characteristics were uneven and a polymer product of stable quality could not be obtained.

その原因は、本発明者等の知見によれば、エチルベンゼ
ン類の脱水素反応によって得られるスチレン類が、その
反応において用いた触媒特性、反応形式、グランドの運
転条件等によって、高不飽和不純物、すなわちフェニル
アセチレン等のアセチレン類、ジオレフィン類などの含
有機が大巾に変動し、これらの高不飽和不純物がスチレ
ン類の重合時に重合抑制剤として働くことによることが
わかった。The cause of this is, according to the findings of the present inventors, that styrene obtained by the dehydrogenation reaction of ethylbenzenes contains highly unsaturated impurities and In other words, it was found that the content of acetylenes such as phenylacetylene and diolefins fluctuated widely, and this is due to the fact that these highly unsaturated impurities act as polymerization inhibitors during the polymerization of styrenes.

従来、スチレン類に含有される高不飽和不純物の除去に
関する文献等は、１）まシ見当らなかった。Conventionally, no literature has been found regarding the removal of highly unsaturated impurities contained in styrenes.

ただわずかに、特公昭４Ｂ−１６４９７号公報には、ニ
ッケル５％以上、及びクロム、マンガン、銅の１種以上
をニッケルに対して５０％以下含有せしめた固体多元触
媒を特定の有機硫黄化合物で処理した触媒を用いて、ス
チレン類を水素添加処理し、含有されているフェニルア
セチレンを選択的に水素添加して除く記載がある。しか
し、同公報に記載の水素添加処理は、液空間速度がわず
か５ｈｒ−’程度であることからして、かかる方法はフ
ェニルアセチレンを選択的に水素添加して除くことがで
きても、工業的に有利に実施できる方ではない。However, Japanese Patent Publication No. 4B-16497 discloses that a solid multi-component catalyst containing 5% or more of nickel and 50% or less of one or more of chromium, manganese, and copper relative to nickel is prepared using a specific organic sulfur compound. There is a description of hydrogenating styrene using a treated catalyst and selectively hydrogenating and removing the phenylacetylene contained therein. However, since the hydrogenation treatment described in the same publication has a liquid hourly space velocity of only about 5 hr-', this method is not suitable for industrial use even though it is possible to selectively hydrogenate and remove phenylacetylene. I am not the type of person who can implement this in an advantageous way.

（発明が解決しようとする問題点） 本発明は含有される高不飽和不純物、すなわちアセチレ
ン類やジオレフィン類を工業的に有利に除去できるスチ
レン類の精製方法を提供しようとするものである。(Problems to be Solved by the Invention) The present invention aims to provide a method for purifying styrenes that can industrially advantageously remove the highly unsaturated impurities contained therein, that is, acetylenes and diolefins.

（ｂ）発明の構成 （問題点を解決するための手段）本 発明者等は、前記の問題点を解決するために種々研究を
重ねた結果、高不飽和不純物、特にフェニルアセチレン
等のアセチレン類を含有するスチレン類を水素添加処理
するに当り、該水素添加反応における水素分圧を２　ｋ
ｌｉｌ　／　ｃｍ”以下に保つことによって、高不飽和
不純物のみを選択的に水素添加して除去できることを見
出し、本発明に到達したのである。(b) Structure of the Invention (Means for Solving the Problems) As a result of various studies to solve the above problems, the present inventors have found that highly unsaturated impurities, especially acetylenes such as phenylacetylene, When hydrogenating styrene containing styrene, the hydrogen partial pressure in the hydrogenation reaction is set to 2 k
It was discovered that only highly unsaturated impurities can be selectively hydrogenated and removed by maintaining the hydrogenation temperature at or below 2.li/cm", and the present invention was achieved based on this finding.

すなわち、本発明のスチレン類の精製方法は、スチレン
類を水素添加触媒の存在下で水素添加処理をして含有さ
れる高不飽和不純物を選択的に水素添加して除く方法に
おいて、該水素添加反応における反応系に供給される水
素分圧を２　ｋｇ　／　ｃｍ２以下に保つことを特徴と
する方法である。That is, the method for purifying styrenes of the present invention includes hydrogenating styrenes in the presence of a hydrogenation catalyst to selectively hydrogenate and remove contained highly unsaturated impurities. This method is characterized by maintaining the hydrogen partial pressure supplied to the reaction system in the reaction at 2 kg/cm2 or less.

本発明の精製方法の対象となるスチレン類とは、スチレ
ン、ｐ−メチルスチレン、ビニルトルエン、ｐ−をブチ
ルスチレン、ジビニルベンゼン及ヒこれらの少なくとも
１種を含有する組成物をいう。The styrenes to be subjected to the purification method of the present invention include styrene, p-methylstyrene, vinyltoluene, p-butylstyrene, divinylbenzene, and compositions containing at least one of these.

かかるスチレン類は、通常、エチルベンゼン、ｐ−’ｆ
Ａ／エチルＲンゼン、エチルトルエン、ｐ−をブチルエ
チルベンゼン、ジエチルベンゼン等の少なくとも１種の
エチルベンゼン類を脱水素触媒、たとえばＦｅ−Ｃｏ−
Ｋｆ主成分とする触媒（特開昭４９−１２０８８７号、
同４９−１２０８８８号。Such styrenes are usually ethylbenzene, p-'f
A/Ethyl R-benzene, ethyltoluene, p- and at least one kind of ethylbenzene such as butyl ethylbenzene, diethylbenzene, etc., as a dehydrogenation catalyst, such as Fe-Co-
Catalyst containing Kf as main component (JP-A-49-120887,
No. 49-120888.

ｆ８Ｊ　５３−１２９１９０号、及び同５３−１２９１
９１号の各公報等参照）、又はＦｅ　−Ｃｒ　−Ｋ　ｆ
主成分とする触媒等の種々の脱水素触媒の存在下で脱水
素反応をさせて得られる反応生成物、又は同反応生成物
の蒸留分離によって得られる留分等である。f8J No. 53-129190 and No. 53-1291
91, etc.), or Fe -Cr -K f
These include reaction products obtained by dehydrogenation reaction in the presence of various dehydrogenation catalysts such as catalysts as main components, or fractions obtained by distillation separation of the reaction products.

上記のような方法で得られるスチレン類には、フェニル
アセチレン等のアセチレン類、及びジオレフィン類が含
まれている。スチレン類中に含有されるかかる高不飽和
不純物の含有社は、製造条件等によっても異なるが、ア
セチレン類が１０〜１０１０００ｐｐ重量）程度、ジオ
レフィン類が５〜５００　ｐｐｍ　（１瓜）程度である
。The styrenes obtained by the above methods include acetylenes such as phenylacetylene and diolefins. The amount of highly unsaturated impurities contained in styrenes varies depending on the manufacturing conditions, etc., but it is about 10 to 101,000 ppm (by weight) for acetylenes and about 5 to 500 ppm (1 melon) for diolefins. .

本発明の精製方法で使用する水素添加触媒は、水素添加
触媒能を有するものであればよい。好ましいその触媒は
白金拠金属を触媒成分として含有する触媒である。この
種の水素添加触媒は、通常、その触媒成分が適当な担体
に担持されており、その触媒成分の担持駄は通常、０．
０１〜１重社係、好ましくは０．０５〜０．５重置チで
ある。また、そイソウ土、多孔性粘土などの天然無機物
担体等があげられる。The hydrogenation catalyst used in the purification method of the present invention may be any catalyst as long as it has hydrogenation catalytic ability. Preferred catalysts are those containing a platinum-based metal as a catalyst component. In this type of hydrogenation catalyst, the catalyst component is usually supported on a suitable carrier, and the amount of the catalyst component supported is usually 0.
01 to 1, preferably 0.05 to 0.5. Also included are natural inorganic carriers such as sorghum earth and porous clay.

本発明の精製方法の特徴は、前記したようにその水素添
加反応を水素分圧２　ｋｇ　／　ｃｍ２以下、好ましく
は１　ｋｌ　／　ｃｍ”以下で行なわせる点にある。そ
の水素分圧が高すぎるとスチレン等の有用なスチレン類
が水素添加されてロスになるし、その水素分圧があまり
低くすぎると目的の高不飽和不純物を有効に水素添加し
て除くことができなくなる。As mentioned above, the feature of the purification method of the present invention is that the hydrogenation reaction is carried out at a hydrogen partial pressure of 2 kg/cm2 or less, preferably 1 kl/cm" or less. If the hydrogen partial pressure is too high, Useful styrenes such as styrene are hydrogenated and lost, and if the hydrogen partial pressure is too low, the target highly unsaturated impurities cannot be effectively removed by hydrogenation.

また、水素添加反応の全圧は１通常、常圧〜加圧下、好
ましくは常圧〜１０ｋｇ／の２Ｇである。The total pressure of the hydrogenation reaction is usually normal pressure to pressurized, preferably normal pressure to 10 kg/2G.

本発明の水素添加における反応温度は２００℃以下、好
ましくは１００℃〜室温である。その反応温度が高すぎ
るとスチレン等のスチレン類が水素添加されてロスにな
るし、低くすぎると目的の高不飽和不純物の水素添加速
度がおそくなり、工業的実施上の支障となる。The reaction temperature in the hydrogenation of the present invention is 200°C or less, preferably 100°C to room temperature. If the reaction temperature is too high, styrenes such as styrene will be hydrogenated and lost, and if it is too low, the rate of hydrogenation of the target highly unsaturated impurities will be slow, which will be a hindrance to industrial implementation.

本発明の水素添加触媒は、パッチ方式により行なわせる
ことができるし、所定温度に保たれた触媒層ヘスチレン
類及び水素を連続的に供給して反応させる連続方式によ
っても実施することができる。連続方式で反応させる場
合の触媒層へのスチレン類の供給速度は、液空間速度（
Ｌ）ＩｓＶ　）で１〜５００　ｈｒ−’　、好ましくは
１０〜３００ｈｒ−’である。The hydrogenation catalyst of the present invention can be carried out by a patch method, or by a continuous method in which hestyrenes and hydrogen are continuously supplied to a catalyst layer kept at a predetermined temperature and reacted. In the case of continuous reaction, the supply rate of styrene to the catalyst layer is determined by the liquid hourly space velocity (
L)IsV) from 1 to 500 hr-', preferably from 10 to 300 hr-'.

同速度が高すぎるとフェニルアセチレン等の高不飽和不
純物の転化率が低下して、充分に除去できなくなるし、
同速度が低くすぎるとスチレン等の有用なスチレン類が
水素添加されてロスになる。If the same speed is too high, the conversion rate of highly unsaturated impurities such as phenylacetylene will decrease and it will not be possible to remove them sufficiently.
If the same rate is too low, useful styrenes such as styrene will be hydrogenated and will be lost.

本発明における水素添加反応系への水素の供給量は、目
的の高不飽和不純物の水素添加に必要な水素量の１〜１
００倍１程度である。供給する水素量が多すぎるとスチ
レン等の有用成分が水素添加されてロスとなプ、その収
量が低下する。The amount of hydrogen supplied to the hydrogenation reaction system in the present invention is 1 to 1% of the amount of hydrogen necessary for hydrogenating the target highly unsaturated impurity.
It is about 00 times 1. If the amount of hydrogen supplied is too large, useful components such as styrene are hydrogenated and lost, resulting in a lower yield.

（実施例等） 以下に、触媒製造例、実施例及び比較例をあげてさらに
詳述する。これらの例に記載のｐｐｍ及びチは特に記載
しない限り重置基準による。(Examples, etc.) Below, catalyst production examples, examples, and comparative examples will be given to further explain in detail. The ppm and chi in these examples are on a superimposed basis unless otherwise specified.

触媒製造例 ３ｍφ×３蛎の円柱型に成形したｒ−アルミナに、濃度
０．６重量係の塩化・ぐラジウム水ｍ液を含浸させ、１
１０℃で１星夜乾燥させた。Catalyst Production Example R-alumina molded into a cylindrical shape of 3 mφ x 3 oysters was impregnated with an aqueous solution of chloride/gladium at a concentration of 0.6 weight.
It was dried for one night at 10°C.

次いで、その乾燥物を水素気流下で４００℃の温度で１
６時時間光処理して、組成がＰｄ　（０，３％）／ｒ　
−ｍ２ｏ３の水素添加触媒を得た。Next, the dried product was heated at a temperature of 400°C under a hydrogen stream for 1 hour.
After 6 hours of light treatment, the composition was Pd (0.3%)/r.
-m2o3 hydrogenation catalyst was obtained.

実施例１ 容Ｊ１２００ｔｄのＳＵＳ製オートクレーブに、スチレ
ン６０％、エチルベンゼン４０％及びフェニルアセチレ
ン９５　ｐｐｍを含有する粗スチレン留分１００ｄｋ仕
込み、これに上記の様にして調製した触媒１．９を加え
、反応温度を室温（２０℃）に保ちながら、水素ガスを
圧入して常圧で２時間反応させた。この反応における反
応系の水素分圧は１．０に９／儒２であった＠ この反応における反応系のスチレン濃度とフェニルアセ
チレン濃度の経時変化は第１図に示すとおりであった〇 比較例１ 水素を圧入して反応系の圧力を２　ｋｌｌ　／　ｃｍ”
　Ｇに保ち、そのほかは実施例１と同様の条件で反応さ
せた。この場合の反応系の水素分圧は３．０　ｋｇ　／
　ｃｍ２であった。Example 1 A 100 dk crude styrene fraction containing 60% styrene, 40% ethylbenzene and 95 ppm of phenylacetylene was charged into a SUS autoclave with a capacity of J1200 td, and the catalyst 1.9 prepared as described above was added thereto, followed by reaction. While keeping the temperature at room temperature (20° C.), hydrogen gas was introduced under pressure and the reaction was carried out at normal pressure for 2 hours. The hydrogen partial pressure in the reaction system in this reaction was 1.0 to 9/F2 @ The time-dependent changes in the styrene concentration and phenylacetylene concentration in the reaction system in this reaction were as shown in Figure 1 〇 Comparative example 1 Pressurize hydrogen to lower the pressure of the reaction system to 2 kll/cm”
The reaction was carried out under the same conditions as in Example 1 except that the temperature was maintained at In this case, the hydrogen partial pressure in the reaction system is 3.0 kg/
It was cm2.

この反応における反応系のスチレン濃度とフェニルアセ
チレン濃度の経時変化は第２図に示すとおりであった。The changes over time in the styrene concentration and phenylacetylene concentration in the reaction system in this reaction are as shown in FIG.

第１図と第２図の対比から明らかなように、比較例１の
場合は、実施例１の場合よりも水素添加によるスチレン
濃度低下（スチレンのロス）が著しい。As is clear from the comparison between FIG. 1 and FIG. 2, in the case of Comparative Example 1, the decrease in styrene concentration (loss of styrene) due to hydrogenation is more remarkable than in the case of Example 1.

比較例２ 粗スチレンの仕込数を１２０ｍＪ、触媒量を０．５ｙ、
反応温度を８０℃にそれぞれ変更し、かつ水素を圧入し
て反応圧力’ｋ　４　ｋｇ／　ｙｒ２Ｇ　（水素分圧５
、０　’に９　／　ｃｍ２）に保ち、そのほかは実施例
１と同様にして反応を行なわせた。Comparative Example 2 The number of crude styrene charged was 120 mJ, the amount of catalyst was 0.5y,
The reaction temperature was changed to 80°C, and hydrogen was pressurized to increase the reaction pressure 'k4 kg/yr2G (hydrogen partial pressure 5
, 0' to 9/cm2), and otherwise carried out the reaction in the same manner as in Example 1.

この反応における反応系のスチレン濃度とフェニルアセ
チレン濃度の経時変化は第３図に示すとおシであった。The time-dependent changes in the styrene concentration and phenylacetylene concentration in the reaction system in this reaction are shown in FIG.

この場合は、実施例１及び比較例１と較べて、スチレン
濃度の低下がさらに著しい。In this case, compared to Example 1 and Comparative Example 1, the decrease in styrene concentration is even more remarkable.

実施例３ 窒素で希釈した水素濃度３０容量チの水素を使用し、反
応圧力を４に９／ｃｍ”Ｇ（水素分圧１．５に９／ｃｍ
２）に保ち、そのほかは比較例２と同一の条件で反応を
行なわせた。Example 3 Hydrogen with a hydrogen concentration of 30 volumes diluted with nitrogen was used, and the reaction pressure was adjusted to 4 to 9/cm"G (hydrogen partial pressure to 1.5 to 9/cm"G).
2), and the reaction was otherwise carried out under the same conditions as in Comparative Example 2.

この反応における反応系のスチレン濃度及びフェニルア
セチレン濃度の経時変化は、第４図に示すとおりであり
、比較例２の場合に較べてスチレン濃度の低下が著しく
少ない。The time-dependent changes in the styrene concentration and phenylacetylene concentration in the reaction system in this reaction are as shown in FIG. 4, and the decrease in styrene concentration is significantly smaller than in Comparative Example 2.

実施例４ 第５図に示すような装置ｔｚｔ用いて連続的に実施例１
で用いた粗スチレン中のフェニルアセチレンの水添反応
を行なった。Example 4 Example 1 was continuously carried out using the apparatus tzt as shown in FIG.
The hydrogenation reaction of phenylacetylene in crude styrene was carried out.

反応方法は、まずＨ爵解槽でＩ（２圧力１ゆ／α２Ｇで
粗スチレン中にＨ２を８解させ、これをＩングで３　ｋ
ｇ　／　ｃｍ２Ｑに昇圧して反応器ヘフィードした。触
媒は実施例１で用いたものと同じものを用いた。The reaction method is to first decompose H2 in crude styrene at 1 pressure/α2G in an H-type decomposition tank, and then dissolve it in an I-type reactor to 3K.
The pressure was raised to g/cm2Q and fed to the reactor. The same catalyst used in Example 1 was used.

反応温度は８０℃、　ＬＨ８Ｖは５０ｈｒ　　で実施し
た。The reaction temperature was 80°C, and LH8V was carried out for 50 hours.

その結果、含有されていたフェニルアセチレンの５０％
が水添されたが、スチレンは殆んど水添されなかった。As a result, 50% of the phenylacetylene contained
was hydrogenated, but styrene was hardly hydrogenated.

［ｅ）発明の効果 本発明の精製方法は、スチレン型中に含まれるフェニル
アセチレン等の不純物を、高い水素添加選択率で除去す
ることができ、その際にスチレン等の有用成分の水素添
加による消耗が少ない。[e) Effects of the Invention The purification method of the present invention can remove impurities such as phenylacetylene contained in the styrene mold with high hydrogenation selectivity, and in this case, it is possible to remove impurities such as phenylacetylene contained in the styrene mold by hydrogenation of useful components such as styrene. Less wear and tear.

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

第１図は実施例１の、第２図は比較例１の、第３図は比
較例２の、そして第４図は実施例３のそれぞれの反応系
におけるスチレン濃度及びフェニルアセチレン濃度の経
時変化を示した図面である。 第５図は本発明の精製方法を連続的に実施する装置の概
略図である。 第１図 第２図 反応時間（分） 第３図 第４図 反応時間（分） ホフフFigure 1 shows the changes over time in the styrene and phenylacetylene concentrations in the reaction systems of Example 1, Figure 2 of Comparative Example 1, Figure 3 of Comparative Example 2, and Figure 4 of Example 3. This is a drawing showing. FIG. 5 is a schematic diagram of an apparatus for continuously carrying out the purification method of the present invention. Figure 1 Figure 2 Reaction time (minutes) Figure 3 Figure 4 Reaction time (minutes) Hoffu

Claims (1)

【特許請求の範囲】 １）スチレン類を水素添加触媒の存在下で水素添加処理
をして含有される高不飽和不純物を選択的に水素添加し
て除く方法において、該水素添加反応における反応系に
供給される水素分圧を２ｋｇ／ｃｍ＾２以下に保つこと
を特徴とするスチレン類の精製方法。 ２）水素分圧が１ｋｇ／ｃｍ＾２以下である特許請求の
範囲第１項記載の方法。[Claims] 1) A method for selectively hydrogenating and removing highly unsaturated impurities contained in styrenes by hydrogenating them in the presence of a hydrogenation catalyst, wherein the reaction system in the hydrogenation reaction is A method for purifying styrenes, characterized by maintaining the partial pressure of hydrogen supplied to 2 kg/cm^2 or less. 2) The method according to claim 1, wherein the hydrogen partial pressure is 1 kg/cm^2 or less.