JPH02185593A - Method of purifying tar-base fractionated quinoline and preventing discoloration thereof with time - Google Patents
Method of purifying tar-base fractionated quinoline and preventing discoloration thereof with timeInfo
- Publication number
- JPH02185593A JPH02185593A JP290389A JP290389A JPH02185593A JP H02185593 A JPH02185593 A JP H02185593A JP 290389 A JP290389 A JP 290389A JP 290389 A JP290389 A JP 290389A JP H02185593 A JPH02185593 A JP H02185593A
- Authority
- JP
- Japan
- Prior art keywords
- quinoline
- tar
- fractionated
- base
- time
- 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.)
- Pending
Links
- SMWDFEZZVXVKRB-UHFFFAOYSA-N Quinoline Chemical compound N1=CC=CC2=CC=CC=C21 SMWDFEZZVXVKRB-UHFFFAOYSA-N 0.000 title claims abstract description 80
- 238000000034 method Methods 0.000 title claims description 17
- 238000002845 discoloration Methods 0.000 title description 2
- 239000002994 raw material Substances 0.000 claims description 8
- 239000012535 impurity Substances 0.000 abstract description 6
- 239000012279 sodium borohydride Substances 0.000 abstract description 4
- 229910000033 sodium borohydride Inorganic materials 0.000 abstract description 4
- 238000003860 storage Methods 0.000 abstract description 4
- 239000003381 stabilizer Substances 0.000 abstract description 2
- WQDUMFSSJAZKTM-UHFFFAOYSA-N Sodium methoxide Chemical compound [Na+].[O-]C WQDUMFSSJAZKTM-UHFFFAOYSA-N 0.000 abstract 3
- 239000000203 mixture Substances 0.000 abstract 1
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 24
- 239000011269 tar Substances 0.000 description 14
- 238000004821 distillation Methods 0.000 description 11
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 9
- 239000000243 solution Substances 0.000 description 9
- 150000001875 compounds Chemical class 0.000 description 7
- QPUYECUOLPXSFR-UHFFFAOYSA-N 1-methylnaphthalene Chemical compound C1=CC=C2C(C)=CC=CC2=C1 QPUYECUOLPXSFR-UHFFFAOYSA-N 0.000 description 6
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 4
- JUJWROOIHBZHMG-UHFFFAOYSA-N Pyridine Chemical compound C1=CC=NC=C1 JUJWROOIHBZHMG-UHFFFAOYSA-N 0.000 description 4
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 4
- 238000004040 coloring Methods 0.000 description 4
- 235000011121 sodium hydroxide Nutrition 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- UFWIBTONFRDIAS-UHFFFAOYSA-N Naphthalene Chemical compound C1=CC=CC2=CC=CC=C21 UFWIBTONFRDIAS-UHFFFAOYSA-N 0.000 description 2
- 229910021529 ammonia Inorganic materials 0.000 description 2
- WPYMKLBDIGXBTP-UHFFFAOYSA-N benzoic acid Chemical compound OC(=O)C1=CC=CC=C1 WPYMKLBDIGXBTP-UHFFFAOYSA-N 0.000 description 2
- 239000011280 coal tar Substances 0.000 description 2
- WSZKUEZEYFNPID-UHFFFAOYSA-N hydrogen sulfate;quinolin-1-ium Chemical compound OS(O)(=O)=O.N1=CC=CC2=CC=CC=C21 WSZKUEZEYFNPID-UHFFFAOYSA-N 0.000 description 2
- UMJSCPRVCHMLSP-UHFFFAOYSA-N pyridine Natural products COC1=CC=CN=C1 UMJSCPRVCHMLSP-UHFFFAOYSA-N 0.000 description 2
- NWUYHJFMYQTDRP-UHFFFAOYSA-N 1,2-bis(ethenyl)benzene;1-ethenyl-2-ethylbenzene;styrene Chemical compound C=CC1=CC=CC=C1.CCC1=CC=CC=C1C=C.C=CC1=CC=CC=C1C=C NWUYHJFMYQTDRP-UHFFFAOYSA-N 0.000 description 1
- 239000005711 Benzoic acid Substances 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- -1 acidic compounds form salts Chemical class 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 230000032683 aging Effects 0.000 description 1
- 239000003905 agrochemical Substances 0.000 description 1
- 150000001448 anilines Chemical class 0.000 description 1
- 229940111121 antirheumatic drug quinolines Drugs 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 150000004984 aromatic diamines Chemical class 0.000 description 1
- 235000010233 benzoic acid Nutrition 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 150000001735 carboxylic acids Chemical class 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 230000002925 chemical effect Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000018044 dehydration Effects 0.000 description 1
- 238000006297 dehydration reaction Methods 0.000 description 1
- 231100000676 disease causative agent Toxicity 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 239000000975 dye Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000005984 hydrogenation reaction Methods 0.000 description 1
- 239000003456 ion exchange resin Substances 0.000 description 1
- 229920003303 ion-exchange polymer Polymers 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 150000002894 organic compounds Chemical class 0.000 description 1
- 239000000825 pharmaceutical preparation Substances 0.000 description 1
- 229940127557 pharmaceutical product Drugs 0.000 description 1
- SIOXPEMLGUPBBT-UHFFFAOYSA-N picolinic acid Chemical compound OC(=O)C1=CC=CC=N1 SIOXPEMLGUPBBT-UHFFFAOYSA-N 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 239000002243 precursor Substances 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 150000003248 quinolines Chemical class 0.000 description 1
- 238000010992 reflux Methods 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 239000011289 tar acid Substances 0.000 description 1
- 239000002641 tar oil Substances 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- 238000005292 vacuum distillation Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Other In-Based Heterocyclic Compounds (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明はコールタールを蒸留して得られるタール中油の
メチルナフタリン留分から回収されるキノリンの精製方
法に関し、更に経時着色性不純物を除去する方法に関す
る。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for purifying quinoline recovered from a methylnaphthalene fraction of oil in tar obtained by distilling coal tar, and furthermore, a method for removing impurities that color over time. Regarding.
キノリンは農薬や染料、医薬等の原料として重要なもの
である。Quinoline is important as a raw material for agricultural chemicals, dyes, medicines, etc.
一般にタール系キノリンは、タール中油から回収される
。Generally, tar-based quinolines are recovered from oil in tar.
タール中油にはタール酸類やナフタリン分を多く含むの
で、これらを除去した後の、メチルナフタリン留分を硫
酸で抽出して、硫酸キノリンとして分離した後、アンモ
ニアで分解して、含水粗製キノリンとし、ついで脱水蒸
留と精製減圧蒸留により、９５％程度の一般用分留キノ
リンを得ている。（特公昭４６−３９６９６号公報参照
）又、用途によっては、再蒸留により、純度を９７％以
上に高めた高純度キノリンも得ている。Since tar oil contains a large amount of tar acids and naphthalene, after these are removed, the methylnaphthalene fraction is extracted with sulfuric acid and separated as quinoline sulfate, which is then decomposed with ammonia to produce hydrous crude quinoline. Then, by dehydration distillation and purification vacuum distillation, a general-purpose fractionated quinoline of about 95% is obtained. (Refer to Japanese Patent Publication No. 46-39696) Also, depending on the application, high purity quinoline with a purity of 97% or more can be obtained by redistillation.
従来、有機化合物の経時着色を防止する方法として、種
々の手段が提案されている。ＮａＯＨのようなアルカリ
性化合物を添加して蒸留する方法もその一つで、例えば
特開昭６０−１．９９８６１号公報では、芳香族ジアミ
ンの精製を
Ｎ ａ ２ ＣＯｓやＮａＯＨの存在下で蒸留している
。Conventionally, various means have been proposed as methods for preventing organic compounds from discoloring over time. One such method is distillation with the addition of an alkaline compound such as NaOH; for example, in JP-A-60-1.99861, aromatic diamines are purified by distillation in the presence of Na 2 COs or NaOH. ing.
又ピリジン塩基類の着色防止法として、特公昭６０−１
９２９４号公報では、ピリジン塩基類を多孔質イオン交
換樹脂または多孔質吸着樹脂と接触処理する方法も提案
されている。In addition, as a method for preventing coloration of pyridine bases,
No. 9294 also proposes a method in which pyridine bases are brought into contact with a porous ion exchange resin or a porous adsorption resin.
タール系分留キノリンは、貯蔵中に、数時間程度で変色
しはじめ、１ケ月も経過すると黒色に着色する性質があ
る。医薬品等の原料用に使用するものは、特に着色製品
は著しく価値を減するため経時着色を起こさせる原因物
質の除去が強く望まれている。Tar-based fractionated quinoline has the property of starting to change color within a few hours during storage, and turning black after a month has passed. For products used as raw materials for pharmaceutical products, especially colored products, the value is significantly reduced, so it is strongly desired to remove the substances that cause coloration over time.
かかる分留キノリンの経時着色の原因物質や着色のメカ
ニズムについては未だ明確にされていないが、タール系
分留キノリンには、一般に安息香酸やピリジンカルボン
酸のようなカルボン酸類、トルメチルフェノールのよう
な高沸点タール酸及びアニリン誘導体等の微量の不純物
が含まれており、これらの不純物の内のある化合物が何
らかの関係をもっているものと考えられる。分留キノリ
ンの経時着色を防止する方法については、未だ有効な方
法は見い出されておらず、これの解決方法が望まれてい
た。Although the causative agents and coloring mechanisms of fractionated quinoline over time have not yet been clarified, tar-based fractionated quinoline generally contains carboxylic acids such as benzoic acid and pyridinecarboxylic acid, and tolumethylphenol. It contains trace amounts of impurities such as high-boiling tar acid and aniline derivatives, and it is thought that certain compounds among these impurities are somehow related. No effective method has yet been found for preventing coloration of fractionated quinoline over time, and a solution to this problem has been desired.
本発明の目的はタール系分留キノリンの精製方法および
その経時着色を防止する方法を提供することである。An object of the present invention is to provide a method for purifying tar-based fractionated quinoline and a method for preventing coloration thereof over time.
本発明者等は前記の課題を解決するため鋭意研究を行っ
た。その結果、アルカリ性化合物としてＣＨＯＮａのメ
タノール溶液を蒸留時に分留キノリンに添加するのが有
効であることを見い出した。またかくて精製されたキノ
リンにＮ ａ Ｂ Ｈ４を５０〜３００ ｐｐｍ添加す
るとタール系分留キノリンの経時着色を著しく防止し得
ることを見い出して本発明を完成した。The present inventors conducted extensive research to solve the above problems. As a result, it was found that it is effective to add a methanol solution of CHONa as an alkaline compound to the fractionated quinoline during distillation. The present invention was also completed based on the discovery that when 50 to 300 ppm of NaBH4 was added to the thus purified quinoline, coloration of tar-based fractionated quinoline over time could be significantly prevented.
本発明はタール系分留キノリンを蒸留して純度を高める
際、蒸留原料に対し、ＣＨ３０Ｎ ａを添加することを
特徴とするタール系分留キノリンの精製方法である。The present invention is a method for purifying tar-based fractionated quinoline, which is characterized by adding CH30Na to the distillation raw material when distilling the tar-based fractionated quinoline to improve its purity.
又、この方法で精製されたタール系分留キノリンにＮ
ａ Ｂ Ｈ４を５０〜３００ｐｐＩ１１添加することを
特徴とするタール系分留キノリンの経時着色防止方法で
ある。In addition, N is added to the tar-based fractionated quinoline purified by this method.
a B This is a method for preventing discoloration of tar-based fractionated quinoline over time, which is characterized by adding 50 to 300 ppI11 of H4.
以下本発明の詳細な説明する。The present invention will be explained in detail below.
本発明で取扱うタール系分留キノリンとは、タール中油
から回収された含水粗製キノリンを脱水処理した後の、
粗製キノリン留分を蒸留して、９５％程度の純度のキノ
リン留分を得る際に適用し得ることは勿論であるが、経
時的な面からは、着色を望まない用途向けのもの、例え
ば純度９５％程度のキノリン留分が貯蔵中に変色又は着
色しているものの一部を、特殊用途向けに再蒸留して純
度を高める際に適用するのがより望ましい。The tar-based fractionated quinoline handled in the present invention is obtained by dehydrating the hydrous crude quinoline recovered from oil in tar.
Of course, it can be applied to distilling a crude quinoline fraction to obtain a quinoline fraction with a purity of about 95%, but from the perspective of aging, it can also be applied to applications where coloring is not desired, such as purity It is more desirable to apply this method when a part of the 95% quinoline fraction, which is discolored or colored during storage, is redistilled to increase purity for special purposes.
ＣＨｓ ＯＮ ａは通常メタノール溶液にＮａを溶解し
たものであるが、ＣＨａ ＯＮ ａメタノール溶液とし
ては、ＣＨ３０Ｎ ａとして２０〜４０重量％の濃度の
ものがよい。CHs ON a is usually a methanol solution in which Na is dissolved, but the CH3ON a methanol solution preferably has a concentration of 20 to 40% by weight as CH30Na.
ＣＨｓ ＯＮ ａのメタノール溶液の蒸留原料への添加
量としては、ＣＨｓ ＯＮ ａとして１１〜２重量％、
好ましくは０．１５〜１．５重量％である。The amount of methanol solution of CHs ON a added to the distillation raw material is 11 to 2% by weight as CHs ON a;
Preferably it is 0.15 to 1.5% by weight.
０．１重量％未満ては効果が認められず、２重量％を超
えると蒸留借銭中にＮａ分が残留し、燃料等に利用する
際に不利益となるうえに、コスト的に不利であり、効果
もむしろ低下しやすい。アルカリ性化合物として、ＣＨ
ａ ＯＮ ａのメタノール溶液が好適なのは、これが分
留キノリン蒸留原料に可溶なためである。なおＮａＯＨ
水溶液では、蒸留原料に均一に溶解せず効果が少ない。If it is less than 0.1% by weight, no effect will be recognized, and if it exceeds 2% by weight, Na content will remain in the distillate, which is disadvantageous when used as fuel, etc., and is also disadvantageous in terms of cost. Yes, and the effectiveness is likely to decrease. As an alkaline compound, CH
A methanol solution of a ON a is preferred because it is soluble in the fractional quinoline distillation feed. Note that NaOH
In an aqueous solution, it does not dissolve uniformly in the distillation raw material and has little effect.
更に、このようにして得られた分留キノリンに対して、
安定剤としてＮ ａ Ｂ Ｈ４を５０〜３００ｐｐｍ
、好ましくは１００ ｐｐｍ前後添加すると、経時着色
を更に長期にわたり抑制できる。Furthermore, for the fractionated quinoline obtained in this way,
50-300 ppm of N a B H4 as a stabilizer
, preferably at around 100 ppm, it is possible to suppress coloring over time for a longer period of time.
この理由については、ＮａＢＨ４は７０〜８０℃で分解
して、Ｈ２を発生することが知られており、これによっ
て製品中での水添作用により、各種不純物を安定化させ
るものと推定される。The reason for this is that NaBH4 is known to decompose at 70 to 80°C and generate H2, which is presumed to stabilize various impurities through hydrogenation in the product.
蒸留原料にアルカリ性化合物を添加することにより蒸留
製品の経時着色を抑制できるが、これはある種の酸性化
合物が、アルカリ性化合物と塩を形成したり、あるいは
ある種の不純物がアルカリ性化合物の触媒作用により重
合物へ転化する等の化学的な作用が生ずることにより蒸
留製品中の経時着色原因物質またはその前駆物質の含有
量が減少したためであると推定している。By adding an alkaline compound to the distillation raw material, it is possible to suppress the coloration of the distilled product over time, but this is because certain acidic compounds form salts with alkaline compounds, or certain impurities are caused by the catalytic action of alkaline compounds. It is presumed that this is because the content of the coloring-causing substance or its precursor substance in the distilled product decreased over time due to chemical effects such as conversion to a polymer.
コールタールを蒸留してえられるメチルナフタレン留分
（キノリンを１０％含有）を３０％硫酸で抽出してえら
れる硫酸キノリンをアンモニアで分解して粗製キノリン
をうる。この粗製キノリンからえられる純度９５％の着
色したキノリン留分に２７％ＣＨｓ ＯＮ ａメタノー
ル溶液を蒸留原料に対しＣＨ３０Ｎ ａとして０ 、
１〜５ ｖｔ％の範囲で種々に変えて添加し、各々１０
０°／３ｈ還流する。次いで１７０ ｌｌｌｍＨｇαａ
の減圧下で精密蒸留し、前留分と後留分約５％を除いた
純度９７％の製品キノリンを得た。A methylnaphthalene fraction (containing 10% quinoline) obtained by distilling coal tar is extracted with 30% sulfuric acid, and the obtained quinoline sulfate is decomposed with ammonia to obtain crude quinoline. A colored quinoline fraction with a purity of 95% obtained from this crude quinoline was added with a 27% CHsONa methanol solution to the distilled raw material as CH30Na0,
They were added in various amounts in the range of 1 to 5 vt%, and each
Reflux at 0°/3h. Then 170 lllmHgαa
Precision distillation was carried out under reduced pressure to obtain product quinoline with a purity of 97%, excluding about 5% of the pre-distillate and post-distillate.
製品キノリンの試料をガラス容器に採り密閉し暗所に保
存し、適当な間隔をおいて着色度（ハーゼンＮ０８）を
観察した。ハーゼンＮｏ、の測定法はＪＩＳＫ−２４２
３，９，色の試験方法による。A sample of the product quinoline was taken in a glass container, sealed and stored in a dark place, and the degree of coloration (Hazen N08) was observed at appropriate intervals. The measurement method for Hazen No. is JISK-242.
3.9. According to the color test method.
種々の条件の試料の着色度の推移を第１表に示す。なお
、比較のためにＣＨａ ＯＮ ａのメタノール溶液を添
加しない他は実施例と同一条件で蒸留処理した場合につ
いても第１表に示した。Table 1 shows the changes in the degree of coloring of the samples under various conditions. For comparison, Table 1 also shows the case where the distillation treatment was carried out under the same conditions as in the example except that the methanol solution of CHa ON a was not added.
又各再蒸留品に対して更にＮ ａ Ｂ Ｈ４を１１００
ｐｐ添加した場合についても第１表に併せて示す。Additionally, 1100 N a B H4 was added to each redistilled product.
The case where pp is added is also shown in Table 1.
第１表
〔発明の効果〕
従来の単純な再蒸留品は貯蔵中３０１」以内に、ハーゼ
ンＮｏ、で５００番以上に着色していた。水沫の製品は
Ｎ ａ ＯＨｓのメタノール溶液を加えて、蒸留しただ
けで、Ｎ ａ Ｂ Ｈ４を添加しない製品でも３ケ月経
過しても３００番以内に保持できる。Table 1 [Effects of the Invention] Conventional simple redistilled products were colored to Hazen No. 500 or higher within 301" during storage. The water droplet product is simply distilled by adding a methanol solution of NaOHs, and even a product without adding NaBH4 can maintain the number within 300 even after 3 months.
更にＮ ａ Ｂ Ｈ４を添加したものは、３ケ月経過後
でも、１３０番以内に保持できる。Furthermore, the one to which NaB H4 was added can maintain the number within 130 even after three months have passed.
Claims (1)
蒸留原料に対し、ＣＨ＿３ＯＮａを添加することを特徴
とするタール系分留キノリンの精製方法。 ２、請求項１記載の方法で精製されたタール系分留キノ
リンにＮａＢＨ＿４を５０〜３００ｐｐｍ添加すること
を特徴とするタール系分留キノリンの経時着色防止方法
。[Claims] 1. When distilling tar-based fractionated quinoline to increase its purity,
A method for purifying tar-based fractionated quinoline, which comprises adding CH_3ONa to a distilled raw material. 2. A method for preventing coloration of tar-based fractionated quinoline over time, which comprises adding 50 to 300 ppm of NaBH_4 to the tar-based fractionated quinoline purified by the method according to claim 1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP290389A JPH02185593A (en) | 1989-01-11 | 1989-01-11 | Method of purifying tar-base fractionated quinoline and preventing discoloration thereof with time |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP290389A JPH02185593A (en) | 1989-01-11 | 1989-01-11 | Method of purifying tar-base fractionated quinoline and preventing discoloration thereof with time |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH02185593A true JPH02185593A (en) | 1990-07-19 |
Family
ID=11542314
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP290389A Pending JPH02185593A (en) | 1989-01-11 | 1989-01-11 | Method of purifying tar-base fractionated quinoline and preventing discoloration thereof with time |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH02185593A (en) |
-
1989
- 1989-01-11 JP JP290389A patent/JPH02185593A/en active Pending
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