JP2000007937A - Oxidizing treatment of carbon black - Google Patents

Oxidizing treatment of carbon black

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Publication number
JP2000007937A
JP2000007937A JP19096598A JP19096598A JP2000007937A JP 2000007937 A JP2000007937 A JP 2000007937A JP 19096598 A JP19096598 A JP 19096598A JP 19096598 A JP19096598 A JP 19096598A JP 2000007937 A JP2000007937 A JP 2000007937A
Authority
JP
Japan
Prior art keywords
carbon black
furnace
stage
gas
bulk density
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
Application number
JP19096598A
Other languages
Japanese (ja)
Inventor
Yasunari Osaki
泰成 大▲崎▼
修七 ▲吉▼村
Shushichi Yoshimura
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Chemical Corp
Original Assignee
Mitsubishi Chemical Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Mitsubishi Chemical Corp filed Critical Mitsubishi Chemical Corp
Priority to JP19096598A priority Critical patent/JP2000007937A/en
Publication of JP2000007937A publication Critical patent/JP2000007937A/en
Pending legal-status Critical Current

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Abstract

PROBLEM TO BE SOLVED: To enable oxidizing treatment of a powder carbon black extremely efficiently, in large quantities and continuously by subjecting the powder carbon black prepared by a furnace-type manufacturing oven to gas-phase oxidization treatment at a specific stage. SOLUTION: A powder furnace carbon black at a stage at which it has just generated by thermal cracking after charging a raw material oil in a furnace-type manufacturing furnace and its bulk density has not reached 0.15 g/cc is subjected to gas-phase oxidation treatment. This stage is a stage at which the carbon black has not received handling at the outlet of a collection bag filter or it may pass through another bag filter if the bulk density remains below 0.15 g/cc. The oxidation reaction is conducted in the gas phase in a reaction tube by using air as a diluent, with an oxidizing agent concentration being 1-30 g/Nm3 and a flow rate being 5-40 m/s. The oxidizing agent is added in an amount to give an oxidation degree of 1-20 wt.%. Gas-phase oxidizing agents include ozone, nitrogen dioxide and the like, but not specifically limited to.

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【0001】[0001]

【発明の属する技術分野】本発明は、粉末状カーボンブ
ラックの酸化処理方法に関するものであり、詳しくは、
ファーネス式製造炉を用いて製造したカーボンブラック
の酸化処理方法に関するものであり、更に詳しくは粉末
状カーボンブラックを空気、オゾン、二酸化窒素等の気
相酸化剤を用いて酸化反応させる際に、酸化剤と粉末状
カーボンブラック表面との接触反応を効率よく行わせ
て、インキ、塗料等の用途に好適なカーボンブラックを
有利に製造する方法に関するものである。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for oxidizing powdery carbon black.
The present invention relates to a method for oxidizing carbon black produced using a furnace-type production furnace, and more particularly, to oxidizing powdered carbon black using a gas phase oxidizing agent such as air, ozone, or nitrogen dioxide. The present invention relates to a method for efficiently producing a carbon black suitable for applications such as inks and paints by efficiently performing a contact reaction between an agent and the surface of a powdery carbon black.

【0002】[0002]

【従来の技術】酸化処理されたカーボンブラックは、未
酸化処理カーボンブラックと比較して、黒度、光沢、流
動性等のインキ、塗料適性に優れ、多岐、多方面で汎用
的に使用されている、付加価値の高いカーボンブラック
である。粉末状カーボンブラックの酸化処理方法におい
ては、カーボンブラックを、使用用途に応じ、その酸化
処理の程度を変更し、酸化反応させ、目的とするカーボ
ンブラックを製造する方法が知られている。
2. Description of the Related Art Compared with unoxidized carbon black, oxidized carbon black has excellent blackness, gloss, fluidity, etc., suitability for inks and paints, and is widely used in a wide variety of fields. High value-added carbon black. As a method of oxidizing powdered carbon black, a method is known in which the degree of oxidizing treatment of carbon black is changed according to the intended use, and an oxidative reaction is performed to produce the desired carbon black.

【0003】なお、酸化処理の程度は普通、酸化処理
度、即ち、カーボンブラックに対する酸化剤の重量比率
で示される。しかしながら、反応させる粉末状カーボン
ブラックの特性で、ジブチルフタレート吸油量(以下、
DBPという)が低く、又粒子径の小さい銘柄について
は、元々嵩密度が高く、更に工程を経る中でハンドリン
グによる高嵩密度化が促進され、酸化処理温度を上げて
も酸化処理効率が悪く、所望の品質が得られないという
問題があった。
[0003] The degree of oxidation treatment is usually indicated by the degree of oxidation treatment, that is, the weight ratio of oxidizing agent to carbon black. However, due to the properties of the powdered carbon black to be reacted, the dibutyl phthalate oil absorption (hereinafter, referred to as
DBP) is low, and the brand having a small particle size has a high bulk density from the beginning, further promotes high bulk density by handling in the course of the process, and has a poor oxidation treatment efficiency even when the oxidation treatment temperature is increased. There was a problem that desired quality could not be obtained.

【0004】また、一旦、高嵩密度になった粉末状カー
ボンブラックの嵩密度を下げる手段として、攪拌機を用
いる方法又はエアーレーション等により、カーボンブラ
ックを解砕する方法が考えられるが、これらはいずれ
も、カーボンブラックに強制的なシェア(shear)
をかけることとなるため、カーボンブラックの分散化・
低嵩密度化が進む一方で、部分的に粉末状カーボンブラ
ックの凝集・粒状化が進行し、酸化剤との処理反応にお
いて、局部的にカーボンブラックの分散化が抑制され、
そのため、酸化処理における反応効率の低下や反応ムラ
を引き起こすという問題が生起し、好ましくない結果を
招く。
As a means for lowering the bulk density of the powdered carbon black once having a high bulk density, a method using a stirrer or a method of pulverizing the carbon black by aeration or the like can be considered. Also forced to share carbon black (shear)
To disperse carbon black.
While the low bulk density progresses, the aggregation and granulation of the powdered carbon black partially progresses, and in the treatment reaction with the oxidizing agent, the dispersion of the carbon black is locally suppressed,
For this reason, there occurs a problem that the reaction efficiency in the oxidation treatment is lowered or a reaction unevenness is caused, resulting in an undesirable result.

【0005】他方、特開平3−124773号公報記載
の方法では、酸化処理効率を上げる為、酸化処理する際
に、予め粉末状カーボンブラック中の水分を加熱乾燥除
去する方法及び加熱乾燥時に発生する凝集カーボンブラ
ックを分級除去する方法が示されている。しかし、これ
らの方法は、分級による粉末状カーボンブラックの収率
の低下を招き、該当処理装置の建設コストを増大させ、
更に、加熱乾燥処理には時間がかかる為、大型連続処理
プラントへ適用するには、問題があった。
On the other hand, in the method described in Japanese Patent Application Laid-Open No. 3-124773, in order to increase the efficiency of the oxidation treatment, a method of heating and removing moisture in the powdered carbon black in advance during the oxidation treatment and a method of generating the heat during the heating and drying. A method for classifying and removing agglomerated carbon black is disclosed. However, these methods cause a reduction in the yield of powdered carbon black due to classification, increase the construction cost of the processing equipment,
Furthermore, since the heating and drying treatment takes a long time, there is a problem when applied to a large-scale continuous processing plant.

【0006】[0006]

【発明が解決しようとする課題】従来のファーネス式製
造炉で生成した粉末状カーボンブラックは、燃焼ガスを
はじめとするガスとの分離・捕集、搬送、そして貯蔵と
いった製造プラントでの工程を経る中で、デンス化・凝
集化し、嵩密度が0.2g/cc以上に達する非常な高
嵩密度化が促進される。このような高嵩密度化したカー
ボンブラックを酸化剤と気相反応させた場合、カーボン
ブラックの分散が悪く、その結果、酸化剤との接触面積
の低減による、反応効率の低下並びに反応ムラを引き起
こし、生産性及び品質面に悪影響を及ぼしていた。本発
明者等はこのような従来法の問題点を解決すべく鋭意研
究した結果、極めて効率的に、且つ大量連続的に、粉末
状カーボンブラックを酸化処理する方法を完成した。
The powdery carbon black produced in a conventional furnace-type production furnace undergoes processes in a production plant such as separation / collection, transport, and storage of gases such as combustion gas. Among them, the densification and agglomeration and the extremely high bulk density reaching bulk density of 0.2 g / cc or more are promoted. When such a high bulk density carbon black is subjected to a gas phase reaction with an oxidizing agent, the dispersion of the carbon black is poor, and as a result, a reduction in the contact area with the oxidizing agent causes a reduction in the reaction efficiency and an uneven reaction. , Productivity and quality were adversely affected. The present inventors have made intensive studies to solve such problems of the conventional method, and as a result, have completed a method for oxidizing powdery carbon black very efficiently and continuously in large quantities.

【0007】[0007]

【課題を解決するための手段】本発明は、ファーネス式
製造炉に原料油を装入し、熱分解反応にて生成された直
後から嵩密度が0.15g/ccに達しないまでの段階
の粉末状カーボンブラックに、気相酸化処理を施すこと
を特徴とするカーボンブラックの酸化処理方法に関す
る。
According to the present invention, a raw material oil is charged into a furnace type production furnace, and the bulk oil is produced from a pyrolysis reaction until the bulk density does not reach 0.15 g / cc. The present invention relates to a carbon black oxidation treatment method, which comprises subjecting powdered carbon black to a gas phase oxidation treatment.

【0008】[0008]

【発明の実施の形態】以下本発明を詳細に説明する。本
発明で用いる粉末状カーボンブラックは、通常のファー
ネス式製造炉に原料油を供給し、熱分解する方法により
製造することができる。例えば、1000〜2000℃
の高温雰囲気下、ファーネス式製造炉に原料油を装入
し、熱分解反応によりカーボンブラックを生成させ、水
で急冷した後、捕集バグフィルターにて、ガスを分解
し、捕集することにより製造することができる。
DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. The powdery carbon black used in the present invention can be produced by a method in which a raw material oil is supplied to a usual furnace type production furnace and thermally decomposed. For example, 1000-2000 ° C
In a high-temperature atmosphere, the raw material oil is charged into a furnace type production furnace, carbon black is generated by a thermal decomposition reaction, quenched with water, and then decomposed and collected by a collecting bag filter. Can be manufactured.

【0009】本発明の酸化処理方法においては、粉末状
カーボンブラックは、原料油の熱分解反応により生成し
た直後から嵩密度が0.15g/ccに達しないまでの
段階で行うことが必要である。嵩密度は、JIS K6
221に準拠して測定した値である。この段階とは、捕
集バグフィルター出口の、ハンドリングを受けていな段
階、また、嵩密度が0.15g/ccに達しないままで
あればその後別のバグフィルターを経過したものでもか
まわない。このように粉末状カーボンブラックの嵩密度
が0.15g/ccに達しない状態で、且つカーボンブ
ラック表面が活性状態に在る粉末状カーボンブラック
に、酸化剤を反応させる。また酸化反応時には、空気を
希釈剤として、酸化剤濃度1〜30g/Nm3 、流速5
〜40m/sでの範囲で適宜選択して、反応管中で気相
反応させればよい。
In the oxidation treatment method of the present invention, it is necessary to perform the powdered carbon black in a stage from immediately after being produced by the thermal decomposition reaction of the raw oil until the bulk density does not reach 0.15 g / cc. . Bulk density is JIS K6
221 is measured. This stage may be a stage at the outlet of the collecting bag filter that has not been handled, or a stage after another bag filter has passed since the bulk density does not reach 0.15 g / cc. As described above, the oxidizing agent is reacted with the powdered carbon black in which the bulk density of the powdered carbon black does not reach 0.15 g / cc and the carbon black surface is in an active state. At the time of the oxidation reaction, air is used as a diluent, the oxidant concentration is 1 to 30 g / Nm 3 , and the flow rate is 5
A gas phase reaction in a reaction tube may be appropriately selected within a range of from 40 m / s to 40 m / s.

【0010】酸化反応の際の酸化処理度は、最終製品の
グレードに応じて、適宜選択することができるが、具体
的には酸化処理度1〜20重量%で酸化剤を添加する。
気相酸化剤は、具体的には、オゾン、二酸化窒素等が挙
げられるが、特にこれらに限定されるものではない。酸
化処理された粉末状カーボンブラックは、ニューマチッ
クにて輸送され、バグフィルターにて、酸化処理粉末状
カーボンブラックを捕集後、製品タンクに貯蔵して製品
として搬出される。この方法による酸化効率向上は、特
に凝集性、付着性の高い、DBPで110ml/100
g以下、且つ窒素比表面積で50m2 /g以上のカーボ
ンブラックに、特に効果がある。
The degree of oxidation treatment at the time of the oxidation reaction can be appropriately selected according to the grade of the final product. Specifically, the oxidizing agent is added at an oxidation treatment degree of 1 to 20% by weight.
Specific examples of the gas-phase oxidizing agent include ozone and nitrogen dioxide, but are not particularly limited thereto. The oxidized powdered carbon black is transported by pneumatic, collected by the bag filter, collected in an oxidized powdered carbon black, stored in a product tank, and carried out as a product. Oxidation efficiency improvement by this method is particularly high in cohesiveness and adhesion.
g and a carbon black having a nitrogen specific surface area of 50 m 2 / g or more are particularly effective.

【0011】[0011]

【実施例】以下、実施例を挙げて、本発明を更に具体的
に説明するが、本発明はこれら実施例に制限されるもの
ではない。なお、例中DBP、揮発分及び嵩密度はJI
S K6221に準拠し、窒素表面積はASTM D3
037に準拠して測定した。
EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. In the examples, DBP, volatile matter and bulk density were determined by JI
According to SK6221, nitrogen surface area is ASTM D3
037.

【0012】実施例1 ファーネス式製造炉から製出した粉末状カーボンブラッ
クを、捕集バグフィルターにてガスと分離・捕集し、そ
の直後の未凝集、表面活性な、嵩密度0.134g/c
cの粉末状カーボンブラックを、反応管中でオゾン発生
装置より発生したオゾンと気相反応させた。酸化処理し
た粉末状カーボンブラックは、ニューマチック輸送によ
り、バグフィルターに導通し、酸化処理粉末状カーボン
ブラックを分離・捕集し、製品タンクに貯蔵した。
Example 1 Powdery carbon black produced from a furnace type production furnace was separated and collected from a gas by a collecting bag filter, and immediately thereafter, unagglomerated, surface active, bulk density 0.134 g / c
The powdery carbon black of c was allowed to undergo a gas phase reaction with ozone generated from an ozone generator in a reaction tube. The oxidized powdered carbon black was passed through a bag filter by pneumatic transport, and the oxidized powdered carbon black was separated and collected, and stored in a product tank.

【0013】酸化処理度は4.9重量%とし、この時の
オゾン濃度は、8.1g/Nm3 、反応流速は、9.8
m/sとした。この酸化処理粉末状カーボンブラック
の、酸化効率の指標である、酸化処理前と酸化処理後の
カーボンブラック揮発分差(以下、ΔVMという)は、
1.97%であった。なお、これは後記比較例1で得ら
れたカーボンブラックに比較して22%の向上となっ
た。反応条件及び得られた結果を表−1にまとめて記載
した。
The degree of oxidation treatment is 4.9% by weight, the ozone concentration at this time is 8.1 g / Nm 3 , and the reaction flow rate is 9.8.
m / s. The difference between the carbon black volatile matter before and after the oxidation treatment (hereinafter referred to as ΔVM), which is an index of the oxidation efficiency of the oxidation-treated powdered carbon black, is as follows:
1.97%. This is a 22% improvement over the carbon black obtained in Comparative Example 1 described later. Table 1 summarizes the reaction conditions and the results obtained.

【0014】比較例1 ファーネス式製造炉から製出した粉末状カーボンブラッ
クを、捕集バグフィルターにてガスと分離・捕集し、ニ
ューマチック輸送し、バグフィルターを通して空気と分
離・捕集後、酸化処理用原料タンクに貯蔵した。タンク
内で、粉末状カーフボンブラックの自圧等により、0.
200g/ccと高嵩密度となった粉末状カーボンブラ
ックを反応管中でオゾン発生装置より発生したオゾンと
気相反応させた。
Comparative Example 1 Powdery carbon black produced from a furnace type production furnace was separated and collected from gas by a collecting bag filter, pneumatically transported, and separated and collected from air through a bag filter. It was stored in a raw material tank for oxidation treatment. In the tank, the pressure of the powdered calf bon black is reduced to 0.
Powdered carbon black having a high bulk density of 200 g / cc was subjected to a gas phase reaction with ozone generated from an ozone generator in a reaction tube.

【0015】酸化処理した粉末状カーボンブラックは、
ニューマチック輸送により、バグフィルターに導通し、
酸化処理粉末状カーボンブラックを分離・捕集し、製品
タンクに貯蔵した。酸化処理度、酸化剤濃度、反応流速
は、実施例1と同様とした。この酸化処理粉末状カーボ
ンブラックのΔVMは、1.61%であった。反応条件
及び得られた結果を表−1にまとめて記載した。
The oxidized powdered carbon black is
By pneumatic transport, it conducts to the bag filter,
The oxidized powdered carbon black was separated and collected, and stored in a product tank. The degree of oxidation treatment, oxidant concentration, and reaction flow rate were the same as in Example 1. ΔVM of the oxidized powder carbon black was 1.61%. Table 1 summarizes the reaction conditions and the results obtained.

【0016】比較例2 比較例1と同様にして製出し、酸化処理用原料タンクに
貯蔵した粉末状カーボンブラックを不二パウダル製、F
2S−3型パルベライザーを用いて酸化処理用原料タン
ク出口の0.238g/ccの高嵩密度粉末状カーボン
ブラックを、嵩密度0.178g/ccに強制解砕し、
酸化処理度、酸化剤濃度、反応流速は実施例1と同様に
して反応管中でオゾンと気相反応させて酸化処理カーボ
ンブラックを製造した。
Comparative Example 2 Powdered carbon black produced in the same manner as in Comparative Example 1 and stored in the raw material tank for oxidation treatment was manufactured by Fuji Paudal.
Using a 2S-3 type pulverizer, 0.238 g / cc high bulk density powdered carbon black at the outlet of the oxidation treatment material tank was forcibly disintegrated to a bulk density of 0.178 g / cc,
The oxidation degree, the oxidizing agent concentration, and the reaction flow rate were the same as in Example 1 to produce an oxidized carbon black by gas phase reaction with ozone in a reaction tube.

【0017】解砕により、粉末状カーボンブラックの嵩
密度は低下したが、その低下度合は少なく、又得られた
酸化処理粉末状カーボンブラックのΔVMの値は比較例
1で得られたものと略同等であった。同様に、反応条件
及び得られた結果を表−1にまとめて記載した。
Although the bulk density of the powdered carbon black was reduced by the pulverization, the degree of the reduction was small, and the value of ΔVM of the obtained oxidized powdered carbon black was substantially the same as that obtained in Comparative Example 1. It was equivalent. Similarly, the reaction conditions and the obtained results are summarized in Table 1.

【0018】[0018]

【表1】 [Table 1]

【0019】[0019]

【発明の効果】本発明によれば、粉末状カーボンブラッ
クの酸化処理を効率良く行うことができ、インキ・塗料
着色剤として優れた酸化処理粉末状カーボンブラック製
造上益するところ大である。
According to the present invention, the oxidizing treatment of powdered carbon black can be carried out efficiently, and the production of oxidized powdered carbon black which is excellent as a colorant for inks and paints is greatly improved.

Claims (1)

【特許請求の範囲】[Claims] 【請求項1】 ファーネス式製造炉に原料油を装入し、
熱分解反応にて生成された直後から嵩密度が0.15g
/ccに達しないまでの段階にある粉末状カーボンブラ
ックに、気相酸化処理を施すことを特徴とするカーボン
ブラックの酸化処理方法。
A raw material oil is charged into a furnace type production furnace,
Immediately after being generated by the thermal decomposition reaction, the bulk density is 0.15 g
A method for oxidizing carbon black, which comprises subjecting the powdered carbon black to a stage not reaching / cc in a gas phase oxidation process.
JP19096598A 1998-06-23 1998-06-23 Oxidizing treatment of carbon black Pending JP2000007937A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP19096598A JP2000007937A (en) 1998-06-23 1998-06-23 Oxidizing treatment of carbon black

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP19096598A JP2000007937A (en) 1998-06-23 1998-06-23 Oxidizing treatment of carbon black

Publications (1)

Publication Number Publication Date
JP2000007937A true JP2000007937A (en) 2000-01-11

Family

ID=16266632

Family Applications (1)

Application Number Title Priority Date Filing Date
JP19096598A Pending JP2000007937A (en) 1998-06-23 1998-06-23 Oxidizing treatment of carbon black

Country Status (1)

Country Link
JP (1) JP2000007937A (en)

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* Cited by examiner, † Cited by third party
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