JPH0237896B2 - - Google Patents
Info
- Publication number
- JPH0237896B2 JPH0237896B2 JP58084156A JP8415683A JPH0237896B2 JP H0237896 B2 JPH0237896 B2 JP H0237896B2 JP 58084156 A JP58084156 A JP 58084156A JP 8415683 A JP8415683 A JP 8415683A JP H0237896 B2 JPH0237896 B2 JP H0237896B2
- Authority
- JP
- Japan
- Prior art keywords
- tar
- distillation
- acid
- column
- distillation column
- 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 - Lifetime
Links
- 238000004821 distillation Methods 0.000 claims description 40
- 239000011269 tar Substances 0.000 claims description 27
- 239000011289 tar acid Substances 0.000 claims description 22
- 239000007800 oxidant agent Substances 0.000 claims description 18
- 239000002253 acid Substances 0.000 claims description 16
- 150000007513 acids Chemical class 0.000 claims description 16
- 150000003839 salts Chemical class 0.000 claims description 8
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims description 6
- 150000002989 phenols Chemical class 0.000 claims description 6
- 150000003739 xylenols Chemical class 0.000 claims description 6
- 238000004519 manufacturing process Methods 0.000 claims description 5
- -1 permanganate Chemical compound 0.000 claims description 5
- 239000000126 substance Substances 0.000 claims description 4
- 239000002641 tar oil Substances 0.000 claims description 4
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims description 3
- 230000002378 acidificating effect Effects 0.000 claims description 3
- 239000003513 alkali Substances 0.000 claims description 3
- 150000001896 cresols Chemical class 0.000 claims description 3
- 229910017604 nitric acid Inorganic materials 0.000 claims description 3
- 239000000203 mixture Substances 0.000 claims 1
- QWVGKYWNOKOFNN-UHFFFAOYSA-N o-cresol Chemical compound CC1=CC=CC=C1O QWVGKYWNOKOFNN-UHFFFAOYSA-N 0.000 description 12
- 150000003573 thiols Chemical class 0.000 description 10
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 8
- 238000000034 method Methods 0.000 description 7
- 239000012535 impurity Substances 0.000 description 6
- 239000011280 coal tar Substances 0.000 description 5
- RLSSMJSEOOYNOY-UHFFFAOYSA-N m-cresol Chemical compound CC1=CC=CC(O)=C1 RLSSMJSEOOYNOY-UHFFFAOYSA-N 0.000 description 5
- 229940100630 metacresol Drugs 0.000 description 5
- 150000003464 sulfur compounds Chemical class 0.000 description 5
- 238000000605 extraction Methods 0.000 description 4
- 238000009835 boiling Methods 0.000 description 3
- 230000018044 dehydration Effects 0.000 description 3
- 238000006297 dehydration reaction Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- 229910052739 hydrogen Inorganic materials 0.000 description 3
- RMVRSNDYEFQCLF-UHFFFAOYSA-N thiophenol Chemical compound SC1=CC=CC=C1 RMVRSNDYEFQCLF-UHFFFAOYSA-N 0.000 description 3
- 238000000998 batch distillation Methods 0.000 description 2
- 238000007670 refining Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- QTWJRLJHJPIABL-UHFFFAOYSA-N 2-methylphenol;3-methylphenol;4-methylphenol Chemical compound CC1=CC=C(O)C=C1.CC1=CC=CC(O)=C1.CC1=CC=CC=C1O QTWJRLJHJPIABL-UHFFFAOYSA-N 0.000 description 1
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 description 1
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 229920000297 Rayon Polymers 0.000 description 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- 239000003905 agrochemical Substances 0.000 description 1
- 239000012670 alkaline solution Substances 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 239000013064 chemical raw material Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000004040 coloring Methods 0.000 description 1
- 150000001875 compounds Chemical class 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
- 238000005336 cracking Methods 0.000 description 1
- 229930003836 cresol Natural products 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 239000000284 extract Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910000037 hydrogen sulfide Inorganic materials 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 238000004445 quantitative analysis Methods 0.000 description 1
- 239000002964 rayon Substances 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000010802 sludge Substances 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
- 239000004094 surface-active agent Substances 0.000 description 1
- 238000010189 synthetic method Methods 0.000 description 1
- 238000005292 vacuum distillation Methods 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
Landscapes
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Description
この発明は、コールタール中に含有されるター
ル酸類を分離精製する方法に係り、特に、コール
タールを蒸留して得られるタール軽油、カルボル
油、ナフタリン油、吸収油等タール系油を苛性ソ
ーダ等のアルカリ水溶液で抽出して得られる粗製
タール酸塩からタール酸類を遊離させ、これを蒸
留して純度の高いタール酸類を得る方法に関す
る。
タール酸類は、コールタールから分離されたフ
エノール類を総称するものであり、例えば、フエ
ノール、オルトクレゾール、メタ・パラクレゾー
ル、キシレノール、その他の高沸点フエノール類
がある。そして、これらのタール酸類は、樹脂、
界面活性剤、医薬、農薬等の用途の化学原料とし
て重要であり、合成法によつても製造されている
が、コールタールからも分離され上記用途に使用
されている。
しかしながら、コールタールを蒸留して得られ
るタール系油中には非常に多くの化合物が含有さ
れており、このタール系油からアルカリ抽出によ
つて得られるタール酸中にも不純物が混入する。
そして、この不純物については、それがタール酸
の蒸留精製の際に分離除去し得るものであれば問
題はないが、タール系油中には硫黄化合物、特に
硫化水素、アルキルメルカプタン類、チオフエノ
ール類等のチオール類が存在し、これが不純物と
してタール酸中に混入してくる。この硫黄化合
物、特にチオール類は、その化学的性質がフエノ
ール類と類似しており、通常の蒸留によつては分
離し除去することが難かしく、しかも、タール酸
中に不純物として存在して発臭や着色等の問題を
引き起す。
本発明者等は、かかる観点に鑑み、硫黄化合物
を可及的に分離除去し得るタール酸類の製造法に
ついて鋭意研究を重ねた結果、粗製タール酸を脱
水した後蒸留してタール酸類を製造する際に蒸留
に先がけて酸化剤を添加することにより硫黄化合
物、特にチオール類の留出を防止し、不純物が少
く、かつ、発臭や着色が改善されることを見い出
し、本発明に到達したものである。
すなわち、本発明は、タール系油をアルカリ抽
出し、得られたタール酸塩を酸性物質で分解して
粗製タール酸とし、この粗製タール酸を脱水蒸留
した後、初留塔を経て１又は２以上の蒸留塔でフ
エノール、クレゾール類、キシレノール類等のタ
ール酸類を蒸留分離するに当り、初留塔の塔頂留
出油又は初留塔より後の蒸留塔に装入されるター
ル酸類に、過酸化水素、過マンガン酸塩及び硝酸
から選ばれた酸化剤を添加して蒸留するタール酸
類の製造法である。
本発明において、タール系油をアルカリ抽出
し、タール酸をタール酸塩として回収し、このタ
ール酸塩を酸性物質で分解して粗製タール酸を得
るまでの工程としては従来公知の方法を採用する
ことができる。
そして、本発明においては、上記粗製タール酸
を脱水した後蒸留してフエノール、クレゾール
類、キシレノール類等のタール酸を製造する際に
蒸留に先がけて酸化剤を添加するものであり、酸
化剤を添加するのは初留塔より後の蒸留前であ
る。
この粗製タール酸の蒸留として、初留塔、フエ
ノール塔、オルトクレゾール塔、メタクレゾール
塔及び回分蒸留塔等を使用して連続的に蒸留を行
う方法を採用する場合、酸化剤は、初留塔の塔頂
留出液に添加してもよく、さらには各蒸留塔に装
入される被処理油中にそれぞれ添加してもよい。
なお、酸化剤の添加を初留塔以前の蒸留前、例
えば初留塔に装入される脱水タール酸に添加した
場合は、チオフエノール以外の重質硫黄化合物を
多量含んでいるためか、酸化剤の添加による脱チ
オフエノール効果が低い。
また、本発明で使用される酸化剤は、不純物と
して含有される硫黄化合物、特にチオール類を酸
化若しくは重質化して蒸留の際に留出するのを防
止する作用をするものであり、過酸化水素、過マ
ンガン酸塩、硝酸、等の種々の酸化剤を使用する
ことができ、また、これらの酸化剤を２種以上組
合せて使用することもできる。これらの酸化剤の
うち、過酸化水素は、蒸留した際にスラツジの発
生がなく、また、腐食の問題も発生しないことか
ら特に好ましいものである。
なお、特開昭56−115731号公報には、タール酸
塩又は粗製タール酸に空気等の酸素含有ガスでエ
アレーシヨンを行う方法が記載されているが、チ
オール類の除去効果は低く、特に製品中へのチオ
ール類の留出を効率良く完全に防止することは困
難である。
上記酸化剤は、通常溶液として脱水タール酸に
添加されるもので、溶剤としては水、底沸点アル
コール等の蒸留した際にタール酸類と容易に分離
できるものがよい。この酸化剤は、蒸留に付され
るタール酸に対して、通常100ppm以上、好まし
くは1000〜5000ppm使用する。
酸化剤を添加した後の蒸留は、連続式又は回分
式の減圧蒸留装置が使用される。そして、蒸留塔
は、その塔内最高温度、すなわち塔底温度が200
℃を越えない範囲で行なわれる。塔底温度が200
℃を越えると酸化剤の添加により酸化又は重質化
した硫黄化合物が再分解して蒸留の際に留出し、
製品タール酸中に不純物として混入してくる。従
つて、各蒸留塔での減圧度は、上記塔底温度と蒸
留の対象となるタール酸の沸点との関係で定ま
る。
以下、本発明方法を実施例に基づいて具体的に
説明する。
実施例 １
タール系油を脱油塔に装入し、アルカリ抽出を
行つてその塔底からタール酸塩を抜き出し、この
タール酸塩をガス分解塔に装入してCO2ガスと接
触させて粗製タール酸を遊離せしめ、この粗製タ
ール酸を水等で洗浄した後脱水塔に装入して脱水
し、その塔底から得られた脱水タール酸を初留塔
に装入してキシレノール以上の留分を塔底から抜
き出すと共に、その塔頂留出油についてはフエノ
ール塔、オルトクレゾール塔及びメタクレゾール
塔に順次装入してフエノール、オルトクレゾール
及びメタ・パラクレゾールを製品として取り出
し、また、初留塔及びメタクレゾール塔の塔底油
については回分蒸留塔に装入してキシレノール等
を製品として取り出すようにしたフエノール製造
工程から、以下のような試料をサンプリングし
た。
試料Ａ：脱水塔へ装入する直前の粗製タール酸
Ｂ：初留塔の塔頂留出油
Ｃ：メタクレゾール塔の塔頂留出油
上記各試料Ａ，Ｂ，Ｃについて、酸化剤として
４％KMnO4，４％H2O2，又は30％H2O2の添加
若しくはエアーレヨンを行い、加熱温度151〜179
℃、減圧度310mmHg、留出温度147〜175℃、留出
量85〜90重量％の条件で減圧蒸留を行つた。
得られた留出油についてチオール類の定量分析
を行い、留出油中に残留する硫黄分定量した。結
果を第１表に示す。
The present invention relates to a method for separating and refining tar acids contained in coal tar, and in particular, a method for separating and refining tar acids contained in coal tar. The present invention relates to a method of liberating tar acids from crude tar salts obtained by extraction with an aqueous alkaline solution and distilling the same to obtain highly pure tar acids. Tar acids are a general term for phenols separated from coal tar, and include, for example, phenol, ortho-cresol, meta-para-cresol, xylenol, and other high-boiling phenols. And these tar acids are resin,
It is important as a chemical raw material for uses such as surfactants, medicines, and agricultural chemicals, and is also produced by synthetic methods, but it is also separated from coal tar and used for the above purposes. However, the tar oil obtained by distilling coal tar contains a large number of compounds, and the tar acid obtained from the tar oil by alkaline extraction also contains impurities.
There is no problem with this impurity if it can be separated and removed during the distillation purification of tar acid, but tar oil contains sulfur compounds, especially hydrogen sulfide, alkyl mercaptans, and thiophenols. There are thiols such as thiols, which are mixed into tar acid as impurities. These sulfur compounds, especially thiols, have chemical properties similar to phenols, and are difficult to separate and remove by ordinary distillation. This causes problems such as odor and coloring. In view of this, the present inventors have conducted extensive research on a method for producing tar acids that can separate and remove sulfur compounds as much as possible, and as a result, they have dehydrated crude tar acid and then distilled it to produce tar acids. The present invention was achieved by discovering that adding an oxidizing agent prior to distillation prevents distillation of sulfur compounds, especially thiols, reduces impurities, and improves odor and coloration. It is. That is, the present invention extracts tar-based oil with alkali, decomposes the obtained tar salt with an acidic substance to obtain crude tar acid, dehydrates and distills this crude tar acid, and then passes it through a first distillation column to 1 or 2 In distilling and separating tar acids such as phenols, cresols, and xylenols in the above distillation column, the top distillate oil of the initial distillation column or the tar acids charged into the distillation column after the initial distillation column are This is a method for producing tar acids by adding and distilling an oxidizing agent selected from hydrogen peroxide, permanganate, and nitric acid. In the present invention, conventionally known methods are employed for the steps of alkali extraction of tar-based oil, recovery of tar acid as a tar salt, and decomposition of this tar salt with an acidic substance to obtain crude tar acid. be able to. In the present invention, an oxidizing agent is added prior to distillation when the crude tar acid is dehydrated and then distilled to produce tar acids such as phenols, cresols, xylenol, etc. It is added after the initial distillation column and before distillation. When a continuous distillation method is adopted for the distillation of this crude tar acid using an initial distillation column, a phenol column, an orthocresol column, a metacresol column, a batch distillation column, etc., the oxidizing agent is added to the initial distillation column. It may be added to the top distillate of the distillation column, or it may be added to the oil to be treated which is charged to each distillation column. Furthermore, if an oxidizing agent is added to the dehydrated tar acid charged to the initial distillation tower before distillation, for example, the oxidizing agent may be added to the dehydrated tar acid charged to the initial distillation tower, which may cause oxidation The effect of removing thiophenol by adding the agent is low. In addition, the oxidizing agent used in the present invention has the effect of oxidizing or making thiols contained as impurities, especially thiols, so as to prevent them from being distilled out during distillation. Various oxidizing agents such as hydrogen, permanganate, nitric acid, etc. can be used, and two or more of these oxidizing agents can also be used in combination. Among these oxidizing agents, hydrogen peroxide is particularly preferred because it does not generate sludge during distillation and does not cause corrosion problems. Although JP-A-56-115731 describes a method in which tar salts or crude tar acid are aerated with oxygen-containing gas such as air, the removal effect of thiols is low, especially in products. It is difficult to efficiently and completely prevent the distillation of thiols. The above-mentioned oxidizing agent is usually added to the dehydrated tar acid as a solution, and the solvent is preferably one that can be easily separated from the tar acids during distillation, such as water or a bottom boiling point alcohol. This oxidizing agent is used in an amount of usually 100 ppm or more, preferably 1000 to 5000 ppm, based on the tar acid to be subjected to distillation. For distillation after adding the oxidizing agent, a continuous or batch vacuum distillation apparatus is used. The distillation column has a maximum temperature inside the column, that is, a bottom temperature of 200
It is carried out within a range that does not exceed ℃. Tower bottom temperature is 200
If the temperature exceeds ℃, sulfur compounds that have been oxidized or made heavier by the addition of an oxidizing agent will be re-decomposed and distilled out during distillation.
It is mixed into the product tar acid as an impurity. Therefore, the degree of pressure reduction in each distillation column is determined by the relationship between the bottom temperature and the boiling point of tar acid to be distilled. Hereinafter, the method of the present invention will be specifically explained based on Examples. Example 1 Tar-based oil is charged into a deoiling tower, subjected to alkaline extraction to extract tar salts from the bottom of the tower, and the tar salts are charged into a gas cracking tower and brought into contact with CO 2 gas. After liberating the crude tar acid and washing it with water etc., it is charged into a dehydration tower for dehydration, and the dehydrated tar acid obtained from the bottom of the tower is charged into an initial distillation tower to produce more than xylenol. The fraction is extracted from the bottom of the column, and the distillate oil from the top of the column is sequentially charged to a phenol column, an ortho-cresol column, and a meta-cresol column to extract phenol, ortho-cresol, and meta-para-cresol as products. The following samples were sampled from a phenol manufacturing process in which the bottom oil of the distillation column and meta-cresol column was charged into a batch distillation column and xylenol etc. were extracted as a product. Sample A: Crude tar acid just before being charged to the dehydration tower B: Top distillate oil from the first distillation tower C: Top distillate oil from the meta-cresol tower For each of the above samples A, B, and C, 4 as the oxidizing agent %KMnO 4 , 4% H 2 O 2 , or 30% H 2 O 2 or air rayon, heating temperature 151-179
Distillation under reduced pressure was carried out under the following conditions: °C, degree of vacuum: 310 mmHg, distillation temperature: 147-175 °C, and distillation amount: 85-90% by weight. The obtained distillate oil was quantitatively analyzed for thiols, and the sulfur content remaining in the distillate oil was determined. The results are shown in Table 1.
【表】
(注) 酸化剤添加量は純量換算であ
る。
実施例 ２
実施例１のフエノール製造工程において、初留
塔の塔頂留出油に酸化剤を添加し、フエノール
塔、オルトクレゾール塔及びメタクレゾール塔の
各塔頂からそれぞれ製品ととしてフエノール、オ
ルトクレゾール及びメタ・パラクレゾールの各留
分を得、これら各留分についてチオール類の定量
分析を行つた。結果を第２表に示す。[Table] (Note) The amount of oxidizing agent added is converted to pure amount.
Example 2 In the phenol production process of Example 1, an oxidizing agent was added to the top distillate oil of the initial distillation column, and phenol and ortho-cresol were produced as products from the tops of the phenol column, ortho-cresol column, and meta-cresol column, respectively. Cresol and meta-para-cresol fractions were obtained, and quantitative analysis of thiols was performed on each of these fractions. The results are shown in Table 2.
Claims (1)
ル酸塩を酸性物質で分解して粗製タール酸とし、
この粗製タール酸を脱水蒸留した後、初留塔を経
て１又は２以上の蒸留塔でフエノール、クレゾー
ル類、キシレノール類等のタール酸類を蒸留分離
するに当り、初留塔の塔頂留出油又は初留塔より
後の蒸留塔に装入されるタール酸類に、過酸化水
素、過マンガン酸塩及び硝酸から選ばれた酸化剤
を添加して蒸留することを特徴とするタール酸類
の製造法。1. Tar oil is extracted with alkali, the obtained tar salt is decomposed with an acidic substance to produce crude tar acid,
After dehydrating and distilling this crude tar acid, it passes through an initial distillation column and is distilled to separate tar acids such as phenols, cresols, and xylenols in one or more distillation columns. Alternatively, a method for producing tar acids, which comprises adding an oxidizing agent selected from hydrogen peroxide, permanganate, and nitric acid to tar acids charged into a distillation column after the initial distillation column and distilling the mixture. .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8415683A JPS59210038A (en) | 1983-05-16 | 1983-05-16 | Production of tar acid |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8415683A JPS59210038A (en) | 1983-05-16 | 1983-05-16 | Production of tar acid |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS59210038A JPS59210038A (en) | 1984-11-28 |
| JPH0237896B2 true JPH0237896B2 (en) | 1990-08-28 |
Family
ID=13822633
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8415683A Granted JPS59210038A (en) | 1983-05-16 | 1983-05-16 | Production of tar acid |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59210038A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6216443A (en) * | 1985-07-12 | 1987-01-24 | Nippon Steel Chem Co Ltd | Method of purifying phenol |
| JP6655646B2 (en) * | 2018-03-27 | 2020-02-26 | Ｊｆｅケミカル株式会社 | Method for producing tar acid |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56115731A (en) * | 1980-02-18 | 1981-09-11 | Nippon Steel Chem Co Ltd | Preparation of tar acid |
-
1983
- 1983-05-16 JP JP8415683A patent/JPS59210038A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56115731A (en) * | 1980-02-18 | 1981-09-11 | Nippon Steel Chem Co Ltd | Preparation of tar acid |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS59210038A (en) | 1984-11-28 |
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