JPH0331693B2 - - Google Patents
Info
- Publication number
- JPH0331693B2 JPH0331693B2 JP29595185A JP29595185A JPH0331693B2 JP H0331693 B2 JPH0331693 B2 JP H0331693B2 JP 29595185 A JP29595185 A JP 29595185A JP 29595185 A JP29595185 A JP 29595185A JP H0331693 B2 JPH0331693 B2 JP H0331693B2
- Authority
- JP
- Japan
- Prior art keywords
- naphthalene
- distillation
- diethanolamine
- benzothiophene
- crude
- 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
- UFWIBTONFRDIAS-UHFFFAOYSA-N Naphthalene Chemical compound C1=CC=CC2=CC=CC=C21 UFWIBTONFRDIAS-UHFFFAOYSA-N 0.000 claims description 82
- 238000000034 method Methods 0.000 claims description 26
- ZBCBWPMODOFKDW-UHFFFAOYSA-N diethanolamine Chemical compound OCCNCCO ZBCBWPMODOFKDW-UHFFFAOYSA-N 0.000 claims description 15
- 238000009835 boiling Methods 0.000 claims description 6
- 238000000895 extractive distillation Methods 0.000 claims description 3
- FCEHBMOGCRZNNI-UHFFFAOYSA-N 1-benzothiophene Chemical compound C1=CC=C2SC=CC2=C1 FCEHBMOGCRZNNI-UHFFFAOYSA-N 0.000 description 26
- 238000004821 distillation Methods 0.000 description 21
- 238000010992 reflux Methods 0.000 description 6
- 238000007796 conventional method Methods 0.000 description 5
- 239000000203 mixture Substances 0.000 description 5
- 150000003464 sulfur compounds Chemical class 0.000 description 4
- WFDIJRYMOXRFFG-UHFFFAOYSA-N Acetic anhydride Chemical compound CC(=O)OC(C)=O WFDIJRYMOXRFFG-UHFFFAOYSA-N 0.000 description 3
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 description 3
- 238000001640 fractional crystallisation Methods 0.000 description 3
- 238000005984 hydrogenation reaction Methods 0.000 description 3
- 239000012535 impurity Substances 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- 238000011084 recovery Methods 0.000 description 3
- 239000002904 solvent Substances 0.000 description 3
- CXWXQJXEFPUFDZ-UHFFFAOYSA-N tetralin Chemical compound C1=CC=C2CCCCC2=C1 CXWXQJXEFPUFDZ-UHFFFAOYSA-N 0.000 description 3
- YNQLUTRBYVCPMQ-UHFFFAOYSA-N Ethylbenzene Chemical compound CCC1=CC=CC=C1 YNQLUTRBYVCPMQ-UHFFFAOYSA-N 0.000 description 2
- VSCWAEJMTAWNJL-UHFFFAOYSA-K aluminium trichloride Chemical compound Cl[Al](Cl)Cl VSCWAEJMTAWNJL-UHFFFAOYSA-K 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000000746 purification Methods 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- QERFBOIKZHJXKN-UHFFFAOYSA-N C1=CC=C2SC=CC2=C1.C1=CC=CC2=CC=CC=C21 Chemical compound C1=CC=C2SC=CC2=C1.C1=CC=CC2=CC=CC=C21 QERFBOIKZHJXKN-UHFFFAOYSA-N 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 239000004927 clay Substances 0.000 description 1
- 239000011280 coal tar Substances 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 238000001944 continuous distillation Methods 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 238000006477 desulfuration reaction Methods 0.000 description 1
- 230000023556 desulfurization Effects 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
- 239000000284 extract Substances 0.000 description 1
- 239000000077 insect repellent Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 239000012452 mother liquor Substances 0.000 description 1
- 150000002790 naphthalenes Chemical class 0.000 description 1
- 150000002898 organic sulfur compounds Chemical class 0.000 description 1
- 235000006408 oxalic acid Nutrition 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Landscapes
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Description
産業上の利用分野
この発明は、95％ナフタレンと通称されている
粗製ナフタレンの精製方法に関する。
従来技術
ナフタレンは、医薬、染料、その他有機合成原
料として重要な物質であるが、それら用途に供す
るためには、十分に製精することが必要である。
一方、その程高純度を要求されない防虫剤向けの
場合であつても、着色着臭していると商品価値が
低いため、その意味からも精製することが必要と
なる。
このため、従来から幾多の精製法が提案されて
いる。例えば、水素添加法（特開昭53−119856
号、特開昭54−144349号）、メタノールからの晶
析法（特公昭47−47020号）、塩化アルミニウム添
加による不純物除去法（特公昭47−47021号）、分
別結晶と白土処理併用法（特公昭47−47023号）、
無水酢酸添加法（特公昭60−3051号）、シユウ酸
添加法（特開昭53−144557号）、金属または金属
酸化物触媒添加法（特開昭54−81247号、特開昭
53−147048号）等が知られている。
上記従来法のうち、工業的規模で実施されてい
る水素添加法においては、ナフタレンの一部が水
素添加されて生成するテトラリンおよびベンゾチ
オフエンの分解生成物であるエチルベンゼンの除
去工程を付加する必要があり、製品歩留も低下す
る。また、同じく分別結晶法においては、硫黄化
合物であるベンゾチオフエンの除去が不十分なた
め、脱硫工程を付加する必要があり、分別母液と
共にナフタレンがロスし、製品歩留が低下する。
その他の従来法も、装置の耐蝕性、製品歩留、
硫黄化合物除去率の点のいずれかに問題を有して
おり、十分満足できるものではない。
一方、ナフタレン−ベンゾチオフエン系では、
比揮発度が低いため、蒸留でベンゾチオフエンを
分離するためには、例えば５％のベンゾチオフエ
ンを含有する粗製ナフタレンから、１％のベンゾ
チオフエン含有ナフタレンを留取するには、理論
段数182段の蒸留塔を用いて還流比20、あるいは、
理論段数122段の蒸留塔では、還流比30が必要で
あるといわれている（Koks ｉ Khimiya No.11
第32〜35頁、1981）。
第１図は、後述する実施例の第１表に示す組成
の粗製ナフタレンを実施例で使用した蒸留装置を
用い、還流比20：１で精密蒸留し、沸点218〜220
℃留分を分取し、分析した結果を示す。
第１図に示す通り、ナフタレン純度は97％と若
干上昇するものの、ベンゾチオフエンの濃度が
2.0％以上となり、不純物はあまり除去されてい
ない。
以上のことは、単なる精密蒸留操作のみによつ
て、粗製ナフタレンから高純度のナフタレンを分
離することがいかに困難で、それが実際的な分離
方法でないことを語るものである。
解決しようとする問題点
この発明は、上記従来技術に代わる簡易で、し
かもナフタレン誘導体合成反応および製品品質等
を阻害する硫黄化合物を除去し得ると共に、製品
歩留りの高い粗製ナフタレンの精製方法を提供す
るものである。
問題点を解決するための手段
本発明者等は、従来法に拘束されない別の視野
に立ち、広く効率的な粗製ナフタレンの精製法を
研究した結果、粗製ナフタレンにジエタノールア
ミンを添加して蒸留に付し、ナフタレンの沸点の
留分を留取することによつて、容易にベンゾチオ
フエンをほぼ完全に除去でき、白色で高純度のナ
フタレンが高収率で取得できることを見出した。
本発明方法が適用されるナフタレンは、従来の
粗製ナフタレンと特に変わらない。本発明方法に
よれば、不純物なかんずく硫黄化合物が除去でき
るところから、コールタール系粗製ナフタレンに
対してきわめて効果的である。
本発明方法において、ナフタレンに対するジエ
タノールアミンの使用量は、８重量倍以上が適当
である。
適用される蒸留塔にも格別な限定はない。棚段
式、充填塔式あるいは泡鐘式等のいずれでもよ
く、また、バツチ式および連続式のいずれの方式
でもよい。
蒸留時の留出温度は、最高常圧下ナフタレンの
沸点たる約218℃であり、真空下では勿論それ以
下の温度となる。この温度はジエタノールアミン
の使用量と共に実験的に求めた値である。
作 用
本発明方法の理論は未だ必ずしも完全には解明
されていない。しかし実験事実から見て、本発明
方法は一種の抽出蒸留と見て差し支えない。
というのは、ジエタノールアミンは蒸留過程で
ベンゾチオフエンをナフタレンより選択的に抽出
し、釜残中に残留させる。一方、抽出され難いナ
フタレンは、ジエタノールアミンと共沸せず、ナ
フタレンの沸点温度で留出してくる。
先に連続蒸留が可能であると述べたのは、抽出
蒸留の常法に従つて抽出剤ジエタノールアミンを
連続的に蒸留塔上部から供給しつつ、蒸留するこ
とができるからである。
具体例
つぎにこの発明方法を実施するに適した工程図
を示す第２図につき説明する。
原料の粗製ナフタレンＫを管路１により、蒸留
塔２の中段に導入し、管路９を経て循環されるジ
エタノールアミン、および管路１０より新たに補
給されるジエタノールアミンＬを蒸留塔２の上段
部分から導入して蒸留に付す。
導入される原料粗製ナフタレンとジエタノール
アミンとの割合は、１：８重量部以上である。
蒸留塔２の塔頂の管路３からは、精製ナフタレ
ンが留出してくるので、その一部を管路５を経て
精製ナフタレンＮとして回収する。還流は、管路
４により、還流比２：１ないし30：１、好ましく
は５：１ないし20：１である。蒸留塔２の塔底部
分からは、ジエタノールアミンと抽出されたベン
ゾチオフエンおよび留出しなかつた若干量のナフ
タレンを含む混合物を管路６を経て抜出し、溶剤
回収塔７に導入する。溶剤回収塔７の塔頂から
は、管路８を経てベンゾチオフエン濃縮物と残存
したナフタレンが留出し、塔底からは、ベンゾチ
オフエンを含まないジエタノールアミンが管路９
により回収され、管路１０から補給されるジエタ
ノールアミンＬと共に、蒸留塔２に循環する。
実施例
第１表に示す組成の粗製ナフタレン58.0ｇに、
ジエタノールアミン464.0ｇを混合し、100mmHg
の真空下、ナフタレンの沸点である144℃以下の
留分49.2ｇを留取した。使用した蒸留装置は、理
論段数50段のヘリパツク充填式で、還流比は20：
１とした。
留取したナフタレンについての物質収支ならび
に分析結果を一括して第２表に示す。
さらに、従来法の水素添加法および分別結晶法
で精製市販されている製品を購入し、分析した結
果を本発明法と比較して第３表に示す。第３表に
示すとおり、本発明法は、製品品質、製品歩留共
優れていることは明らかである。
INDUSTRIAL FIELD OF APPLICATION This invention relates to a method for purifying crude naphthalene, commonly referred to as 95% naphthalene. Prior Art Naphthalene is an important substance as a raw material for medicines, dyes, and other organic synthesis, but in order to use it for these purposes, it is necessary to sufficiently refine it.
On the other hand, even if the product is used for insect repellent, which does not require such high purity, if it is colored and odorized, its commercial value will be low, so it is necessary to purify it for that reason as well. For this reason, many purification methods have been proposed so far. For example, hydrogenation method (JP-A-53-119856
(Japanese Patent Publication No. 54-144349), crystallization method from methanol (Japanese Patent Publication No. 47-47020), impurity removal method by adding aluminum chloride (Japanese Patent Publication No. 47-47021), combined method of fractional crystallization and white clay treatment (Japanese Patent Publication No. 47-47021) Special Publication No. 47-47023),
Acetic anhydride addition method (Japanese Patent Publication No. 60-3051), oxalic acid addition method (Japanese Patent Publication No. 53-144557), metal or metal oxide catalyst addition method (Japanese Patent Publication No. 54-81247,
53-147048) etc. are known. Among the conventional methods mentioned above, in the hydrogenation method implemented on an industrial scale, it is necessary to add a step to remove ethylbenzene, which is a decomposition product of tetralin and benzothiophene, which are produced by hydrogenating a part of naphthalene. , product yield also decreases. Furthermore, in the same fractional crystallization method, since the removal of benzothiophene, which is a sulfur compound, is insufficient, it is necessary to add a desulfurization step, and naphthalene is lost together with the fractionated mother liquor, resulting in a decrease in product yield. Other conventional methods also improve equipment corrosion resistance, product yield,
It has a problem in one of the sulfur compound removal rates and is not fully satisfactory. On the other hand, in the naphthalene-benzothiophene system,
Due to its low specific volatility, in order to separate benzothiophene by distillation, for example, to distill naphthalene containing 1% benzothiophene from crude naphthalene containing 5% benzothiophene, a distillation column with 182 theoretical plates is required. using a reflux ratio of 20, or
It is said that a distillation column with 122 theoretical plates requires a reflux ratio of 30 (Koks i Khimiya No.11
pp. 32-35, 1981). Figure 1 shows crude naphthalene having a composition shown in Table 1 of the Examples described later, which was precisely distilled at a reflux ratio of 20:1 using the distillation apparatus used in the Examples, with a boiling point of 218 to 220.
The results of fractionating and analyzing the °C fraction are shown. As shown in Figure 1, although the naphthalene purity increases slightly to 97%, the concentration of benzothiophene
It is 2.0% or more, and impurities are not removed much. The above demonstrates how difficult it is to separate high-purity naphthalene from crude naphthalene solely by precision distillation, and that this is not a practical separation method. Problems to be Solved The present invention provides a simple method for purifying crude naphthalene that replaces the above-mentioned conventional techniques, can remove sulfur compounds that inhibit the naphthalene derivative synthesis reaction and product quality, and has a high product yield. It is something. Means for Solving the Problems The present inventors have researched a wide range of efficient purification methods for crude naphthalene from a different perspective that is not constrained by conventional methods. However, it has been found that by distilling off the fraction at the boiling point of naphthalene, benzothiophene can be easily removed almost completely and white, highly pure naphthalene can be obtained in high yield. The naphthalene to which the method of the present invention is applied is not particularly different from conventional crude naphthalene. The method of the present invention is extremely effective for treating coal tar-based crude naphthalene since impurities, especially sulfur compounds, can be removed. In the method of the present invention, the appropriate amount of diethanolamine to be used is 8 times or more by weight of naphthalene. There are no particular limitations on the applicable distillation column. Any of the tray type, packed column type, bubble bell type, etc. may be used, and either batch type or continuous type may be used. The distillation temperature during distillation is approximately 218°C, which is the boiling point of naphthalene under normal pressure, and of course is lower than that under vacuum. This temperature was determined experimentally along with the amount of diethanolamine used. Effect The theory of the method of the present invention has not yet been completely elucidated. However, from the experimental facts, the method of the present invention can be regarded as a type of extractive distillation. This is because diethanolamine selectively extracts benzothiophene from naphthalene during the distillation process, leaving it in the bottom of the still. On the other hand, naphthalene, which is difficult to extract, does not azeotrope with diethanolamine and is distilled out at the boiling point temperature of naphthalene. The reason why continuous distillation is possible is that it is possible to carry out distillation while continuously supplying the extractant diethanolamine from the top of the distillation column in accordance with the conventional method of extractive distillation. Specific Example Next, explanation will be made with reference to FIG. 2, which shows a process diagram suitable for carrying out the method of this invention. Crude naphthalene K as a raw material is introduced into the middle stage of the distillation column 2 through pipe 1, and diethanolamine circulated through pipe 9 and diethanolamine L newly supplied through pipe 10 are introduced from the upper stage of the distillation column 2. introduced and subjected to distillation. The ratio of raw material crude naphthalene and diethanolamine to be introduced is 1:8 parts by weight or more. Purified naphthalene is distilled out from a pipe 3 at the top of the distillation column 2, and a part of it is recovered as purified naphthalene N through a pipe 5. The reflux is via line 4 in a reflux ratio of 2:1 to 30:1, preferably 5:1 to 20:1. A mixture containing diethanolamine, extracted benzothiophene, and a small amount of naphthalene that was not distilled out is extracted from the bottom of the distillation column 2 via a pipe 6 and introduced into a solvent recovery column 7. From the top of the solvent recovery column 7, benzothiophene concentrate and remaining naphthalene are distilled out via pipe 8, and from the bottom of the column, diethanolamine containing no benzothiophene is distilled via pipe 9.
is recovered and recycled to the distillation column 2 together with diethanolamine L supplied from the pipe 10. Example 58.0g of crude naphthalene having the composition shown in Table 1,
Mix 464.0g of diethanolamine, 100mmHg
Under vacuum, 49.2 g of a fraction below 144°C, the boiling point of naphthalene, was distilled off. The distillation equipment used was a helipad packed type with 50 theoretical plates, and the reflux ratio was 20:
It was set as 1. The material balance and analysis results for the distilled naphthalene are summarized in Table 2. Furthermore, commercially available products purified by the conventional hydrogenation method and fractional crystallization method were purchased, and the results of analysis are shown in Table 3 in comparison with the method of the present invention. As shown in Table 3, it is clear that the method of the present invention is superior in both product quality and product yield.
【表】【table】
【表】
値
[Table] Value
【表】【table】
【表】
発明の効果
本発明方法は、前述のとおり、粗製ナフタレン
にジエタノールアミンを添加して蒸留するという
簡単な操作で、高純度のナフタレンのみが留分と
して取得でき、従来最も除去困難とされていたベ
ンゾチオフエン等の有機硫黄化合物は、完全に除
去され、また、製品歩留も大幅に向上する。[Table] Effects of the Invention As mentioned above, the method of the present invention is a simple operation in which diethanolamine is added to crude naphthalene and distilled, and only high-purity naphthalene can be obtained as a fraction, which is conventionally considered to be the most difficult to remove. Organic sulfur compounds such as benzothiophene are completely removed, and the product yield is also greatly improved.
第１図は、第１表に示す組成の粗製ナフタレン
を理論段数50段のヘリパツク充填式蒸留装置を用
い、精密蒸留して218〜220℃留分の10％毎のナフ
タレン濃度とベンゾチオフエン濃度をを分析した
結果を示すグラフ、第２図は、本発明の具体的な
実施工程図である。
２…蒸留塔、７…溶剤回収塔、１，３，４，
５，６，８，９，１０…管路、Ｋ…粗製ナフタレ
ン、Ｌ…ジエタノールアミン、Ｎ…精製ナフタレ
ン。
Figure 1 shows the precision distillation of crude naphthalene with the composition shown in Table 1 using a helipack packed distillation apparatus with 50 theoretical plates to determine the naphthalene concentration and benzothiophene concentration in 10% increments of the 218-220°C fraction. FIG. 2, a graph showing the results of the analysis, is a diagram of a specific implementation process of the present invention. 2... Distillation column, 7... Solvent recovery column, 1, 3, 4,
5, 6, 8, 9, 10...pipe line, K...crude naphthalene, L...diethanolamine, N...purified naphthalene.
Claims (1)
して抽出蒸留に付し、ナフタレンの沸点の留分を
留取することを特徴とするナフタレンの精製方
法。1. A method for purifying naphthalene, which comprises adding diethanolamine to crude naphthalene, subjecting it to extractive distillation, and distilling off a fraction at the boiling point of naphthalene.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29595185A JPS62149633A (en) | 1985-12-25 | 1985-12-25 | Purification of naphthalene |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29595185A JPS62149633A (en) | 1985-12-25 | 1985-12-25 | Purification of naphthalene |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62149633A JPS62149633A (en) | 1987-07-03 |
| JPH0331693B2 true JPH0331693B2 (en) | 1991-05-08 |
Family
ID=17827210
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP29595185A Granted JPS62149633A (en) | 1985-12-25 | 1985-12-25 | Purification of naphthalene |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS62149633A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4566302B2 (en) * | 1999-07-15 | 2010-10-20 | 新日鐵化学株式会社 | Method for producing benzothiophene |
-
1985
- 1985-12-25 JP JP29595185A patent/JPS62149633A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS62149633A (en) | 1987-07-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA2300083C (en) | Propylene oxide purification | |
| US2971010A (en) | Production of dicarboxylic acid anhydrides | |
| US2500329A (en) | Azeotropic distillation of 1-butanol from methyl nu-butyl ketone | |
| US2957811A (en) | Segregation of xylene isomers | |
| US4444624A (en) | Process for separating acetone from carbonylation mixtures | |
| US2591713A (en) | Extractive distillation of alcoholcontaining mixtures | |
| US4551208A (en) | Recovery of formic acid by distillation | |
| US4676874A (en) | Separation of n-propyl acetate from n-propanol and water by extractive distillation | |
| US3689372A (en) | Process for separating 2-ciiloro-1,3-butadiene by extractive distillation with dimethylsulfoxide | |
| US4276126A (en) | Separation of ethylene glycol from N-methylpyrrolidone | |
| US2537115A (en) | Extractive distillation of alcohols | |
| JP2924563B2 (en) | Purification method of ethyl acetate | |
| US3616271A (en) | Separation of chloroform and/or ethyl acetate from vinyl acetate by extractive distillation | |
| US3878058A (en) | Recovery of alkylvinylether by extractive distillation of a feed containing only trace amounts of water | |
| US3591463A (en) | Separation of chloroform and/or ethyl acetate and/or methylethyl ketone from vinyl acetate by extractive distillation | |
| JPH0331693B2 (en) | ||
| US5380405A (en) | Separation of alpha-phellandrene from 3-carene by azeotropic distillation | |
| JPH04270249A (en) | Purification of dimethyl carbonate | |
| JP2688515B2 (en) | Method for purifying 2- (4-isobutylphenyl) -propionic acid | |
| JPH032128B2 (en) | ||
| US2676903A (en) | Fractional liquid extraction of vitamins | |
| US3116341A (en) | Method for recovering methylnaphthalenes | |
| DE1224293B (en) | Process for purifying propylene oxide contaminated with methyl formate | |
| US2671052A (en) | Methyl acetate distillation | |
| US2386755A (en) | Purification of hydrocarbons by azeotropic distillation |