JP3902841B2

JP3902841B2 - Production of non-carcinogenic aromatic hydrocarbon oils by solvent extraction and hydrorefining

Info

Publication number: JP3902841B2
Application number: JP28629397A
Authority: JP
Inventors: 巍藤田; 平杉本; 雅美柴田
Original assignee: Nippon Oil Corp
Current assignee: Eneos Corp
Priority date: 1997-09-05
Filing date: 1997-09-05
Publication date: 2007-04-11
Anticipated expiration: 2017-09-05
Also published as: JPH1180755A

Description

【０００１】
【発明の属する技術分野】
本発明は、多環芳香族化合物をほとんど含まない、実質的に非発ガン性の芳香族炭化水素油の製法に関する。特に本発明は、ゴム、インク製品等の製造に使用される石油系芳香族炭化水素油の製法に関し、多環芳香族化合物をほとんど含まない、実質的に非発ガン性の芳香族炭化水素油の製法に関する。
【０００２】
【従来の技術】
一般に石油系芳香族炭化水素油が、原油の精製に於ける減圧蒸留より得られる沸点範囲２６０〜６５０℃の潤滑油製造留分の溶剤抽出精製法において、芳香族炭化水素化合物を豊富に含む留分として製造されている事は当業者によく知られている。従って、原油の種類、抽出精製法の条件によって石油系芳香族炭化水素油は、その性状、化学的組成は異なるものの、基本的に組成成分として芳香族炭化水素化合物を相当量含んでいる事を特徴とする。
【０００３】
この石油系芳香族炭化水素油が、タイヤ等に使用される天然ゴムやＳＢＲ等のゴム用加工油及び原料ＳＢＲの伸展油として有用に使用されている事は当業者によく知られている。即ち、これら石油系芳香族炭化水素油は、上記ゴムとの相溶性を利用してゴムの加工に於ける一連の作業性の改善及び加硫後の最終ゴム製品の物理的性質を改善するために添加されている。
【０００４】
このゴムとの相溶性を発現するために、これら石油系芳香族炭化水素油は典型的に ASTM D 2140 に規定される組成分析法で、実質的に芳香族化合物含有量を意味する芳香環を形成する炭素含有量（以下芳香族炭素含有量、Ｃａ％という事がある）を２７〜５５％含んでいる。
【０００５】
【発明が解決しようとする問題点】
しかしながら、これら石油系芳香族炭化水素油は、成分として含む芳香族炭化水素化合物の中に、更に成分として１５〜２８％の多環芳香族化合物（以下ＰＣＡ（Polycyclic aromatics)という事がある）を含んでいる。近年ＥＵ指令により、この多環芳香族化合物を３％以上含む石油製品は発ガン性ありと勧告された事から、世界的に石油製品の多環芳香族化合物低減の努力がなされている。
【０００６】
ゴム用プロセス油及び伸展油も例外でなく、多くの提案がなされているが、例えば日本特表平６−５０５２４（ＧＢ２２５２９７８，ＵＳ５５０４１３５，ＥＰ５７５４００）号では、粘度が３２〜５０ｃＳｔ．で、ASTM D 2007 に規定されるクレイ−ゲル法による芳香族成分が３０〜５５重量％、飽和炭化水素成分が４０〜６５重量％、且つＩＰ３４６法で測定される多環芳香族化合物即ちＰＣＡが３％未満の石油系炭化水素油を提案しているが、このクレイ−ゲル法による芳香族成分範囲では、ASTM D 2140 に規定される芳香族炭素含有量（Ｃａ％）は２６％に達せず、ゴムとの相溶性及び親和性を発現する事ができないため、従来より使用されてきた石油系芳香族炭化水素油の代替としては不適当なものであり、また特にＳＢＲや天然ゴムに対しては全く使用に耐えないものであった。
【０００７】
更に、ＥＰ０４１７９８０１号では、クレイ−ゲル法による芳香族含有量５０重量％以上、ＩＰ３４６試験法によるＰＣＡ含有量３％未満のゴム用プロセスオイルを、石油系潤滑油留分から２段階抽出法で製造する方法を提案しているが、この方法では、基本的に溶剤抽出によって多環芳香族化合物を除去する際に、極性即ち溶剤との溶解性の似た有用な非多環芳香族化合物をも一緒に溶解抽出して多くのロスを伴うため、目的のプロセスオイルの収率を低くし、且つ２段階抽出による溶剤回収を２回必要とするなど、プロセスコスト的に有利な方法であるとは言い難い。
【０００８】
また日本特表平７−５０１３４６号では、独自の突然変異誘発性指数と物理的特性の関数的な関係を確立し、それに基づくプロセス条件で、炭化水素常圧蒸留残油フィードストックから非発ガン性のブライトストック抽出物または脱れき油を製造する方法が提案されているが、この発明では実質的にＰＣＡ３％未満のＥＵ指令を達しているとは言い難い。
【０００９】
他にも、ＤＥ４０３８４５８号では臨界抽出法による方法、ＷＯ９５２８４５８号では空気酸化作用による方法など提案されているが、いずれも芳香族含有量が低くてゴムとの親和性を欠き、現行のゴム用プロセスオイルの代替に向かないものや、技術的及びプロセス的にコストがかかり過ぎる等、その性能とＥＵ指令による発ガン性勧告即ちＰＣＡ３％未満を同時に満足する、石油系芳香族炭化水素油の技術的にもコスト的にも有利な製造方法は提案されていない。
【００１０】
これより非発ガン性の石油系芳香族炭化水素油の簡単且つ経済的な製造に対する強い要求がある。
【００１１】
【発明の目的】
よって本発明の目的は、ゴム用プロセスオイルとして使用されているＰＣＡを含む現行の石油系芳香族炭化水素油と同等の性能を有する、非発ガン性の石油系芳香族炭化水素油の新規な製造法を提供する事によって、この要求を満足させる事である。特に本発明の目的は、石油の減圧蒸留残さの脱れき油より、溶剤抽出と水素化精製の相関的厳密な操作条件設計によって、簡単で且つ経済的に有利な非発ガン性の石油系芳香族炭化水素油の新規な製造法を提供する事である。
【００１２】
【問題を解決するための手段】
従来よりゴム用プロセスオイルとして使用されている石油系芳香族炭化水素油と同等の性能を有し、且つ発ガン性を有すＩＰ３４６試験法による多環芳香族化合物を３％未満に減じた、安全で環境を汚さない新規な石油系芳香族炭化水素油は、石油の減圧蒸留残さ油の脱れき油を溶剤抽出処理して、ASTM D 2140 に規定される組成分析法による芳香族化合物を形成する炭素含有量３０％以上で且つＩＰ３４６試験法による多環芳香族化合物即ちＰＣＡ含有量８％未満の抽出油を得、該抽出油を多環芳香族化合物を選択的に水素化する条件、特に非多環芳香族化合物を過度に水素添加及び水素化分解させない条件で水素化反応せしめる本発明によって達成される。
【００１３】
本発明に供される原料油は、減圧蒸留残さよりプロパン等の軽質炭化水素により、アスファルト物質を除去された脱れき油が適用される。
【００１４】
減圧蒸留残さの脱れき油は、現行使用されている石油系芳香族炭化水素油の原料となる、沸点２６０〜６５０℃の減圧直留の潤滑油留分に比べて、発ガン性を示す多環芳香族化合物を基本的に少量しか含んでいない事が知られている。
【００１５】
ＥＵ指令による発ガン性の多環芳香族化合物は、厳密に言うとＩＰ３４６試験法によるＤＭＳＯ（ジメチルスルフォキシド）抽出分であり、一般に３〜７環の多環芳香族化合物である。これらの化合物は、現行の石油系芳香族炭化水素油の原料となる減圧蒸留後の潤滑油留分の沸点範囲と概ね一致している。
【００１６】
減圧蒸留残さの脱れき油は、これら潤滑油留分よりはるかに高い沸点範囲を持ち、高分子量の炭化水素化合物より成るので、３〜７環の多環芳香族化合物を基本的に少量しか含まない事が、本発明に好適に用いられる必須の要件となっている。
【００１７】
減圧蒸留残さの脱れき油は、他の減圧蒸留後の潤滑油留分の様な石油炭化水素油と同様に、炭化水素化合物組成としてパラフィン、ナフテン、アロマティックの炭化水素構造の異なる化合物の混合物である。現行ゴム用プロセスオイルとして使用されている芳香族炭化水素油は、この内アロマティック化合物をより多く含む化学組成を持ち、故にゴムとの相溶性及び親和性を有し有用に使用されている。
【００１８】
本発明の目的とする芳香族炭化水素油も、芳香族炭素含有量２６％以上の、アロマティック成分をより多く含む有用なゴム用プロセスオイルとする事にある。
【００１９】
従って、減圧蒸留残さの脱れき油をアロマティック化合物をより多く含む芳香族炭化水素油に精製する必要があるが、これは一般に使用されている向流接触型の抽出塔を用いて溶剤抽出法によって達成される。
【００２０】
本発明の抽出操作における溶剤は、芳香族化合物を選択的に溶解するフルフラール、フェノール、ｎ−メチルピロリドン等の極性溶剤が望ましい。これらの溶剤は単独で用いられても良いし、２種以上の混合溶剤として用いる事もできる。
【００２１】
抽出操作に於ける操作条件は、原料油としての減圧蒸留残さの脱れき油の性状、特に芳香族化合物含有量と多環芳香族化合物含有量によって適宜変動させる事ができ、塔頂温度９０〜１２５℃、塔底温度５０〜８５℃、溶剤比１．０〜５．０の範囲で選択される事が好ましい。
【００２２】
減圧蒸留残さは、当然のごとく原油の種類、減圧蒸留の過酷度によってその性状を変化させ、従ってその脱れき油も物理的性状、化学的組成を変化させる。
【００２３】
本発明の抽出操作条件を決定する因子は原料となる脱れき油の化学組成にあり、先ず脱れき油の芳香族化合物含有量が少なければ、抽出操作条件をよりマイルドな条件即ち上記抽出条件の範囲で、塔頂塔底の抽出温度を低くし且つ溶剤比を下げて、抽出油収量を低く抑える条件を選定し、得られる抽出油の芳香族炭素含有量（Ｃａ％）を上げる事ができる。逆に脱れき油の芳香族化合物含有量が多ければ、抽出操作条件をシビアーにして、即ち抽出温度を高くし且つ溶剤比を上げて、抽出油収量を上げる事で得られる抽出油の芳香族炭素含有量（Ｃａ％）を調整する事ができる。
【００２４】
また脱れき油のＰＣＡ含有量が多ければ、上記抽出条件をシビアーにして、即ち抽出温度を高くし且つ溶剤比を上げて、抽出油収量を上げる事で得られる抽出油のＰＣＡ含有量を低く抑える様に調整する。かくして塔頂温度は好ましくは９０〜１２５℃の範囲、更に好ましくは１００〜１２０℃の範囲が望ましい。
【００２５】
塔頂温度は、抽出操作に於ける溶解量及び溶解する留分の極性、即ち溶剤への溶解性を決定する重要な因子で、１２５℃以上になると芳香族化合物のみならず非芳香族化合物の溶解量も増大し、次の水素化精製へ供出される抽出油の芳香族炭素含有量３０％以上を達成する事が難しく、また９０℃以下では多環芳香族化合物と極性の似た芳香族化合物が主として溶解する事になり、次の水素化精製へ供出される抽出油のＰＣＡ含有量を８％以下にする事が難しくなり、結果として次の水素化精製で、芳香族炭素含有量２６％以上且つＰＣＡ含有量３％以下の非発ガン性の有用な芳香族炭化水素油を製造する事が困難となる。よって塔頂温度は９０〜１２５℃の範囲、好適には１００〜１２０℃の範囲が望ましい。
【００２６】
塔底温度は、塔頂温度との差を利用して、溶質の内部環流即ち塔頂で溶剤に溶解したものが塔底のより低い温度で溶出し、塔内を環流する事による抽出操作の溶質選択性に重要な因子となっている。
【００２７】
この意味では塔底温度はより低い温度を採用し、塔頂との温度勾配を大きく取る方が有利であるが、温度勾配を大きく取り過ぎると内部環流が大きくなりすぎ、フラッディング等の現象を引き起こし、抽出操作ができなくなり問題である。
【００２８】
本発明の抽出操作では、塔頂との温度勾配を３０〜４０℃に取った時、最も安定的に抽出操作が達成された。よって塔底温度は塔頂温度と相関的に、即ち温度勾配を３０〜４０℃とする様に、５０〜８５℃の範囲で適用される事が好ましい。
【００２９】
原料流量に対する溶剤流量の比を溶剤比といい、抽出温度と共に抽出溶解量を決定する重要な因子である。
【００３０】
溶剤比は１．０〜５．０、好ましくは１．５〜４．０の範囲である。溶剤比が１．０未満だと、脱れき油の多環芳香族化合物とそれと極性の似た芳香族化合物が主として溶解する事になり、抽出油のＰＣＡ含有量を８％以下にする事が難しくなり、５．０を越えると芳香族化合物のみならず非芳香族化合物の溶解量も増大し、抽出油の芳香族炭素含有量３０％以上を達成する事が難しくなると同時に、多量の溶剤の回収に余分なエネルギーを必要とし、プロセスコスト上不利になる。よって溶剤比は１．０〜５．０が好ましく、１．５〜４．０の範囲が更に望ましい。
【００３１】
この様に脱れき油の性状によって適宜抽出条件を選択する事で、ASTM D 2140 に規定される組成分析法による芳香族化合物を形成する炭素含有量３０％以上で且つＩＰ３４６試験法による多環芳香族化合物含有量即ちＰＣＡ８％以下の抽出油を得る。抽出油のこの性状は、以下に続く水素化処理を比較的低圧から中圧、比較的低温から中温のマイルドな反応条件で、この抽出油を芳香族炭素含有量２６％以上で且つＰＣＡ含有量３％未満の芳香族炭化水素油に仕上げるに、本発明の必須の要件である。
【００３２】
石油の水素化精製は、石油精製業に於いて広く行われているプロセスである。水素化精製の目的は広くその実施形態は、主として軽質燃料油の製造に適用される比較的高温高圧の水素化分解法、主として燃料油の硫黄分を除去させるための水素化脱硫法、主として潤滑油留分の芳香族化合物の核水添による除去に適用される比較的高温高圧の水素化処理、主として潤滑油留分のオレフィン等の不安定物質の水素添加による色仕上げ及び安定性向上に適用される比較的低温低圧の水素化仕上げ、液体炭化水素中のワックス分を選択的に水素化分解する水素化脱ロウ法等多岐にわたる。
【００３３】
本発明の抽出油の水素化精製は、比較的低圧から中圧、比較的低温から中温のマイルドな反応条件を適用する事によって、技術的に容易に且つプロセスコストを有利にする様、脱れき油の抽出工程と相関的に厳密に設計されたものである。
【００３４】
即ち原料として供される抽出油の芳香族炭素含有量とＰＣＡ含有量を限定的に抽出操作で実現し、多環芳香族化合物を水素添加及び水素化分解し、該原料油の非多環芳香族化合物は過度に水素添加及び水素化分解しないマイルドな反応条件で水素化処理する事によって具体化する。
【００３５】
この比較的マイルドな水素化条件を適用するに、本発明に使用する触媒は、無機酸化物担体に担持された鉄、コバルト、ニッケル、モリブデンの１種または２種以上の金属酸化物触媒が好ましく用いられる。これら金属酸化物の担持量は、触媒総重量に対して２３重量％以上である事が好ましい。
【００３６】
石油の水素化反応は、無機酸化物担体の酸性点による分解反応と担持金属による水素化の競争反応であり、触媒の金属担持量を調整する事によりマイルドな反応条件下で十分に水素化反応を進める事ができる。金属酸化物担持量が２３重量％未満では担体の酸性点による分解反応が勝ち、触媒上への炭素質析出など触媒失活を引き起こし好ましくない。
【００３７】
無機酸化物担体は、アルミナ、シリカ、ゼオライト、アルミノシリケート、クレー等が使用されるがこれらに限定されない。シリカとアルミナの混合物が担体として特に好ましい。
【００３８】
触媒は、石油の減圧直留分の様な硫黄含有量の多い石油フィードストック、あるいは二硫化炭素の様な液体硫黄化合物によって、加硫され活性化される。
【００３９】
反応温度は２８０〜３６０℃の範囲、好ましくは３００〜３４０℃の範囲で行う事が適している。過度の反応温度は、原料の多環芳香族化合物の水素添加及び水素化分解のみならず、有用な非多環芳香族化合物の水素添加及び水素化分解を起こし、結果として得られる芳香族炭化水素油の芳香族炭素含有量を２６％以上に保てなくなるので好ましくない。更に過度の温度は原料の分解並びに触媒上への炭素質析出による失活を招く事から、３６０℃を越える温度は用いるべきでない。
【００４０】
反応温度はまた２８０℃以上が好ましい。２８０℃未満の温度では原料抽出油の多環芳香族化合物の水素添加及び水素化分解反応が十分に進行せず、結果としてＰＣＡ３％以下の芳香族炭化水素油を得る事ができなくなる。
【００４１】
原料油の多環芳香族化合物即ちＰＣＡ含有量が８％を越えると、この温度範囲に於いて、得られる芳香族炭化水素油のＰＣＡ含有量を３％未満に減じる事ができないので、該原料油のＰＣＡ含有量を８％以下に、先の抽出工程で調整しておく事は本発明の必須の要件である。
【００４２】
原料抽出油のＰＣＡ含有量は、少なければ少ない程水素化精製の条件はマイルドになり、非多環芳香族化合物の水素添加及び水素化分解も抑えられ好ましい事ではあるが、先の抽出操作に於ける抽出油のＰＣＡ含有量と芳香族炭素含有量は一義的ではないが相関的に変動し、即ちＰＣＡ含有量のより低い抽出油を得ようとすると芳香族炭素含有量もより低くなり、芳香族炭素含有量３０％以上を保てなくなり、その様な原料油からは、この反応温度条件では芳香族炭素含有量２６％以上の芳香族炭化水素油を得る事ができなくなり本発明に適用し難い。従って水素化精製に先立つ抽出操作に於いて、ＰＣＡ含有量８％以下で且つ芳香族炭素含有量３０％以上の抽出油を調整する事が本発明の必須の要件である。
【００４３】
反応の水素圧力は４０〜９０Kg/cm２の範囲が好ましい。この範囲に於いて、本発明の調整された原料抽出油の多環芳香族化合物の選択的な水素添加及び水素化分解が達成され、非多環芳香族化合物の過度な水素添加及び水素化分解を抑える事ができる。
【００４４】
４０Kg/cm２未満の圧力では、原料油の多環芳香族化合物の水素添加及び水素化分解反応が十分に進行せず、結果としてＰＣＡ含有量３％未満の芳香族炭化水素油を得る事がむずかしくなる。更に水素化反応が十分に達成されないため、原料油の分解やそれに伴う触媒上への炭素質析出を引き起こし、触媒の失活を招く事になり問題である。９０Kg/cm２圧力では、原料油の非多環芳香族化合物まで水素添加及び水素化分解してしまうので、結果として芳香族炭素含有量２６％以上の有用な芳香族炭化水素油を得る事が難しくなる。
【００４５】
反応塔に供する原料流量は、充填触媒量に基づく空間速度で、０．５〜３．０ＬＨＳＶの範囲が好ましい。この範囲に於いて、上記の反応条件と共に、本発明の調整された原料抽出油の多環芳香族化合物の選択的な水素添加及び水素化分解が達成され、非多環芳香族化合物の過度な水素添加及び水素化分解を抑える事ができる。
【００４６】
空間速度０．５ＬＨＳＶ未満では、水素添加及び水素化分解反応が進みすぎ、多環芳香族化合物の除去のみならず非多環芳香族化合物までも水素添加及び水素化分解してしまい、結果として芳香族炭素含有量２６％以上の有用な芳香族炭化水素油を得る事が難しくなる。また空間速度３．０ＬＨＳＶを越えると、原料油の触媒表面への接触効率が極端に落ちるため、原料油の多環芳香族化合物の水素添加及び水素化分解反応が進まず、結果として多環芳香族化合物含有量即ちＰＣＡ含有量３％未満の有用な芳香族炭化水素油を得る事が難しくなる。
【００４７】
原料油流量に対する水素流量の比は、本発明に於いて限定的な要件ではないが、２００〜６００sM３/Klの範囲が好ましい。水素流量が２００sM３/Klより低いと、触媒上の炭素質析出を抑えきれず触媒失活を促進するので触媒の寿命を短くし、６００sM３/Klを越えると反応に関与しない水素が多くなりすぎ、プロセスコスト上不利になる。
【００４８】
水素化精製処理を経た本発明の精製油は、最後に水素化精製に併発する低度の水素化分解によって生じた極少量の軽質分解油を、軽質油ストリッピング塔で除去して水素化精製プロダクト即ち芳香族炭化水素油となる。
【００４９】
かくして得られる、本発明の芳香族炭素含有量２６％以上で且つＰＣＡ含有量３％未満の石油系芳香族炭化水素油は、従来より使用されているゴム用プロセスオイルやインク用配合剤と同等の性能を有し、且つ安全で環境を汚さない非発ガン性の石油系芳香族炭化水素油となる。
【００５０】
特に芳香族炭素含有量２６％以上は、２６％未満だとゴムとの相溶性及び親和性が不足し、それを使用したゴム製品の物性、特に引張強度の低下と伸びの低下を引き起こし、添加量を増すとブリードするという点に於いて、本発明の芳香族炭化水素油に必須の要件である。
【００５１】
以下に本発明の実施例を示す。発明は、発明の一層顕著な特徴を示す操作条件から得られるデータと、比較例として示すデータの、以下の実施例によって更に明解に説明され、完全に理解されるであろう。
しかし本発明はこれらの実施例に何等限定されるものではない。
【００５２】
【実施例】
【表１】

表１に本発明で用いた原料油の性状を示す。原料油として用いられる脱れき油は、原油の種類、蒸留精製法の過酷度、脱れき操作の条件によって変動し、その性状はこの２種に限定されないが、概ねそれらを代表するものである。
原料油の性状値は、密度はJIS K 2249（原油及び石油製品−密度試験方法及び密度・質量・容量換算表）の５．振動式密度試験方法、粘度はJIS K 2283（原油及び石油製品−動粘度試験方法及び粘度指数算出方法）、屈折率はJIS C 2101（電気絶縁油試験方法）の１４．４アッベ屈折計による場合、アニリン点はJIS K 2256（石油製品アニリン点及び混合アニリン点試験方法）によって測定した。
【００５３】
【表２】

表２は本発明の抽出処理の結果である。
実施例１は、原料油に脱れき油Ａを用いて、溶剤としてフルフラール、塔頂温度１０２℃、塔底温度６７℃、溶剤比１．８で抽出処理をし、芳香族炭素含有量(Ｃａ％）が３６．０％で且つＰＣＡ含有量４．２％の抽出油を得た。
実施例２は、原料油に脱れき油Ａを用いて、溶剤としてフェノール、塔頂温度１１５℃、塔底温度７６℃、溶剤比２．７で抽出処理し、芳香族炭素含有量（Ｃａ％）が３４．０％で且つＰＣＡ含有量６．７％の抽出油を得た。
実施例３は、原料油に脱れき油Ｂを用いて、溶剤としてフルフラール、塔頂温度１０８℃、塔底温度７２℃、溶剤比３．２で抽出処理をし、芳香族炭素含有量（Ｃａ％）が３５．０％で且つＰＣＡ含有量５．８％の抽出油を得た。
【００５４】
【表３】

表３は本発明によらない抽出処理の結果である。
比較例１〜３は本発明による抽出条件、即ち塔頂温度９０〜１２５℃、塔底温度５０〜８５℃、溶剤比１．０〜５．０の条件を一つでもはずれると、芳香族炭素含有量３０％以上またはＰＣＡ含有量８％以下のどちらか一方を満足できても、芳香族炭素含有量３０％以上で且つＰＣＡ含有量８％以下の、次の水素化精製工程に供出する中間油を得ることができない。
【００５５】
【表４】

表４は本発明による水素化精製の結果を示し、プロダクトは水素化精製で生じた極少量の軽質分解油をストリッピングして得られた芳香族炭化水素油を示す。
実施例４は、実施例１で得られた抽出油を用いて、水素圧７０Kg/cm２、反応温度３２０℃、原料流量１．０ＬＨＳＶ、水素流量４００ＧＨＳＶで水素化処理を行った結果、芳香族炭素含有量３２．５％で且つＰＣＡ含有量２．２％の芳香族炭化水素油を得る事ができた。
実施例５は、実施例１で得られた抽出油を用いて、水素圧４５Kg/cm２、反応温度３４０℃、原料流量０．８ＬＨＳＶ、水素流量５００ＧＨＳＶで水素化処理を行った結果、芳香族炭素含有量３１．０％で且つＰＣＡ含有量２．４％の芳香族炭化水素油を得る事ができた。
実施例６は、実施例２で得られた抽出油を用いて、水素圧９０Kg/cm２、反応温度３４０℃、原料流量１．５ＬＨＳＶ、水素流量６００ＧＨＳＶで水素化処理を行った結果、芳香族炭素含有量３０．５％で且つＰＣＡ含有量１．８％の芳香族炭化水素油を得る事ができた。
実施例７は、実施例３で得られた抽出油を用いて、水素圧８０Kg/cm２、反応温度３６０℃、原料流量２．０ＬＨＳＶ、水素流量５００ＧＨＳＶで水素化処理を行った結果、芳香族炭素含有量３１．５％で且つＰＣＡ含有量２．９％の芳香族炭化水素油を得る事ができた。
【００５６】
【表５】

表５は本発明によらない水素化精製の結果を示し、プロダクトは水素化精製で生じた極少量の軽質油をストリッピングして得られた芳香族炭化水素油を示す。
比較例４〜６は、本発明による抽出操作によって得られた中間油を原料として用い、水素化精製の条件を本発明によらない条件で適用した結果を示す。結果は、本発明による抽出油を原料としても、本発明による水素化精製の条件即ち反応温度２８０〜３６０℃、水素圧４０〜９０Kg/cm２、原料空間速度０．５〜３．０ＬＨＳＶを一つでも外れると、芳香族炭素含有量２６％以上で且つＰＣＡ含有量３％未満の非発ガン性の有用な芳香族炭化水素油を得られない事を示す。
比較例７〜９は、本発明によらない抽出操作によって得られた中間油を原料として用い、水素化精製の条件を本発明の条件で適用した結果を示す。結果は、本発明によらない抽出油を原料とすると、本発明による水素化精製の条件即ち反応温度２８０〜３６０℃、水素圧４０〜９０Kg/cm２、原料空間速度０．５〜３．０ＬＨＳＶを適用しても、芳香族炭素含有量２６％以上で且つＰＣＡ含有量３％未満の非発ガン性の有用な芳香族炭化水素油を得られない事を示す。
【００５７】
【表６】

【表７】

表６は本発明によって得られた芳香族炭化水素油をゴム用プロセスオイルとして検討した結果を示す。
表７は本発明によらない芳香族炭化水素油と従来より使用されている芳香族系ゴム用プロセスオイルの検討結果を示す。
【００５８】
検討に使用したゴム配合は、原料ゴムやカーボンブラック及びプロセスオイル等の配合材料の検討に使われる、JIS K 6383（合成ゴムＳＢＲの試験方法）の標準配合表Ｎｏ．１の非油添ゴム用配合に準じた配合系を使用し、またゴム配合のロールによる混練方法も同試験方法に記載されている方法によって行った。加硫条件は日本合成ゴム製のキュラストメータによって測定した結果より決定し、プレス加硫機によって加硫した。
製品物性の測定は、硬さは JIS K 6301（加硫ゴム物理試験方法）、引張強度と３００％引張応力及び伸びは JIS K 6251（加硫ゴムの引張試験方法）、引裂強度は JIS K 6252（加硫ゴムの引裂試験方法）、オイルブリード性については室温で４８時間放置後の外観目視検査によって行った。
【００５９】
実施例８及び９は、本発明による芳香族炭化水素油の検討結果で、比較例１０の市販のプロセスオイルの結果と比較して全く遜色のない製品物性を示す事が確認された。
比較例１１は本発明によらない炭化水素油の検討結果で、比較例１０の市販のプロセスオイルの結果と比較して、引張強度及び伸びが極端に悪くなり、プロセスオイル配合部数２０部でオイルブリードが観察され、使用に耐えないものである事が確認された。
【００６０】
【発明の効果】
本発明は、以上に説明したように構成されているので、以下に記載されるような効果を奏する。
本発明は、従来よりゴム用プロセスオイルとして使用されている発ガン性の多環芳香族化合物を含む石油系芳香族炭化水素油と同等の性能を有する、非発ガン性の石油系芳香族炭化水素油を、石油の減圧蒸留残さの脱れき油から、溶剤抽出と水素化精製の相関的厳密な操作条件設計によって、簡単で且つ経済的に有利に製造する方法を提供する。
【００６１】
【図面の簡単な説明】
【図１】図１は本発明による工程図である。
【符号の説明】
１抽出塔溶剤ライン
２抽出塔原料油ライン
３抽出塔抽出残油
４抽出塔抽出油ライン
５水素化精製プロダクトライン
６軽質分解油
７芳香族炭化水素油
８熱交換器
９抽出塔
１０水素化精製塔
１１軽質分解油ストリッピング塔[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a process for producing a substantially non-carcinogenic aromatic hydrocarbon oil that is substantially free of polycyclic aromatic compounds. In particular, the present invention relates to a process for producing petroleum aromatic hydrocarbon oils used in the production of rubber, ink products, etc., and substantially non-carcinogenic aromatic hydrocarbon oils that contain almost no polycyclic aromatic compounds. Relates to the manufacturing method.
[0002]
[Prior art]
In general, petroleum aromatic hydrocarbon oil is a solvent-rich refining process for a lube oil production fraction having a boiling point range of 260 to 650 ° C. obtained by vacuum distillation in the refining of crude oil. It is well known to those skilled in the art that it is manufactured as a fraction. Therefore, although petroleum-based aromatic hydrocarbon oils have different properties and chemical compositions depending on the type of crude oil and the conditions of the extraction and refining method, they basically contain a considerable amount of aromatic hydrocarbon compounds as composition components. Features.
[0003]
It is well known to those skilled in the art that this petroleum-based aromatic hydrocarbon oil is usefully used as a processing oil for rubber such as natural rubber and SBR used for tires and the like, and an extension oil for raw material SBR. That is, these petroleum-based aromatic hydrocarbon oils utilize the compatibility with the above rubber to improve a series of workability in rubber processing and improve the physical properties of the final rubber product after vulcanization. It has been added to.
[0004]
In order to develop compatibility with these rubbers, these petroleum aromatic hydrocarbon oils are typically subjected to composition analysis as specified in ASTM D 2140 to form an aromatic ring which substantially means aromatic compound content. It contains 27 to 55% of the carbon content to be formed (hereinafter referred to as aromatic carbon content, sometimes Ca%).
[0005]
[Problems to be solved by the invention]
However, these petroleum aromatic hydrocarbon oils contain 15 to 28% of polycyclic aromatic compounds (hereinafter sometimes referred to as PCA (Polycyclic aromatics)) as an additional component in the aromatic hydrocarbon compounds included as components. Contains. In recent years, according to the EU directive, petroleum products containing 3% or more of this polycyclic aromatic compound have been recommended to be carcinogenic, and therefore efforts are being made worldwide to reduce polycyclic aromatic compounds in petroleum products.
[0006]
Process oils for rubber and extender oils are no exception, and many proposals have been made. For example, in Japanese Patent Publication No. 6-50524 (GB 2252978, US5504135, EP575400), the viscosity is 32 to 50 cSt. The aromatic component by clay-gel method specified in ASTM D 2007 is 30 to 55% by weight, the saturated hydrocarbon component is 40 to 65% by weight, and the polycyclic aromatic compound or PCA measured by the IP346 method is Although petroleum hydrocarbon oils of less than 3% are proposed, the aromatic carbon content (Ca%) specified in ASTM D 2140 does not reach 26% in the range of aromatic components by this clay-gel method. Since it cannot exhibit compatibility and affinity with rubber, it is not suitable as a substitute for petroleum-based aromatic hydrocarbon oils that have been used in the past, and is particularly suitable for SBR and natural rubber. Was unbearable to use.
[0007]
Furthermore, in EP04179801, a process oil for rubber having an aromatic content of 50% by weight or more by a clay-gel method and a PCA content of less than 3% by an IP346 test method is produced from a petroleum-based lubricating oil fraction by a two-stage extraction method. In this method, when removing a polycyclic aromatic compound by solvent extraction, a useful non-polycyclic aromatic compound having similar polarity or solubility in a solvent is also used. This method is advantageous in terms of process cost, such as reducing the yield of the target process oil and requiring solvent recovery by two-stage extraction twice. hard.
[0008]
In JP 7-501346, a functional relationship between a unique mutagenicity index and physical properties is established, and non-carcinogenicity from a hydrocarbon atmospheric distillation residue feedstock is established under process conditions based on the functional relationship. Although a method for producing a natural bright stock extract or dessert oil has been proposed, it is difficult to say that this invention has achieved an EU directive of substantially less than 3% PCA.
[0009]
In addition, DE 4038458 proposes a method based on the critical extraction method, and WO 9528458 proposes a method based on the air oxidation action. However, all of them have low aromatic content and lack affinity with rubber. The technical characteristics of petroleum-based aromatic hydrocarbon oils that satisfy both the performance and the carcinogenicity recommendation by the EU Directive, that is, less than 3% of PCA, such as those that are not suitable for oil replacement and are too expensive in terms of technology and process In addition, no manufacturing method advantageous in terms of cost has been proposed.
[0010]
Thus, there is a strong demand for simple and economical production of non-carcinogenic petroleum-based aromatic hydrocarbon oils.
[0011]
OBJECT OF THE INVENTION
Therefore, an object of the present invention is to provide a novel non-carcinogenic petroleum-based aromatic hydrocarbon oil having performance equivalent to that of current petroleum-based aromatic hydrocarbon oils including PCA used as a process oil for rubber. It is to satisfy this requirement by providing a manufacturing method. In particular, the object of the present invention is to provide a simple and economically advantageous non-carcinogenic petroleum-based fragrance by designing the relative operating conditions of solvent extraction and hydrorefining relative to the devolatilized oil obtained by distillation of petroleum under reduced pressure. It is to provide a novel method for producing a group hydrocarbon oil.
[0012]
[Means for solving problems]
The polycyclic aromatic compound was reduced to less than 3% by the IP346 test method having the same performance as the petroleum aromatic hydrocarbon oil that has been used as a process oil for rubber and having carcinogenicity. A new petroleum-based aromatic hydrocarbon oil that is safe and does not pollute the environment is obtained by subjecting the oil from vacuum distillation residue of petroleum to solvent extraction to form an aromatic compound by the composition analysis method specified in ASTM D 2140. To obtain an extracted oil having a carbon content of 30% or more and an IP346 test method for polycyclic aromatic compounds, that is, a PCA content of less than 8%, and for selectively hydrogenating the polycyclic aromatic compounds, This is achieved by the present invention in which a non-polycyclic aromatic compound is hydrogenated under conditions that do not cause excessive hydrogenation and hydrogenolysis.
[0013]
As the raw material oil to be used in the present invention, a debris oil from which an asphalt substance has been removed by a light hydrocarbon such as propane from a vacuum distillation residue is applied.
[0014]
Degassed oil from the vacuum distillation residue is much more carcinogenic than a lube oil fraction having a boiling point of 260 to 650 ° C., which is a raw material for petroleum aromatic hydrocarbon oils currently used. It is known that it basically contains only a small amount of a ring aromatic compound.
[0015]
Strictly speaking, the carcinogenic polycyclic aromatic compound according to the EU directive is a DMSO (dimethyl sulfoxide) extract by the IP346 test method, and is generally a polycyclic aromatic compound having 3 to 7 rings. These compounds generally coincide with the boiling point range of the lube oil fraction after distillation under reduced pressure, which is a raw material for current petroleum aromatic hydrocarbon oils.
[0016]
The degassed oil from the vacuum distillation residue has a much higher boiling range than these lubricating oil fractions and is composed of high molecular weight hydrocarbon compounds, so it basically contains only 3 to 7 ring polycyclic aromatic compounds. This is an essential requirement that is preferably used in the present invention.
[0017]
As with other petroleum hydrocarbon oils such as lubricating oil fractions after distillation under reduced pressure, the desiccated oil from the vacuum distillation residue is a mixture of compounds with different hydrocarbon structures such as paraffin, naphthene, and aromatic hydrocarbons as the hydrocarbon compound composition. It is. Aromatic hydrocarbon oils that are currently used as process oils for rubber have a chemical composition that contains more aromatic compounds, and are therefore useful and compatible with rubber.
[0018]
The aromatic hydrocarbon oil that is the object of the present invention is also a useful process oil for rubber containing more aromatic components having an aromatic carbon content of 26% or more.
[0019]
Therefore, it is necessary to purify the devolatilized oil from the vacuum distillation residue into an aromatic hydrocarbon oil containing more aromatic compounds, which is a solvent extraction method using a countercurrent contact type extraction tower that is generally used. Achieved by:
[0020]
The solvent used in the extraction operation of the present invention is preferably a polar solvent such as furfural, phenol or n-methylpyrrolidone that selectively dissolves aromatic compounds. These solvents may be used alone or as a mixed solvent of two or more.
[0021]
The operating conditions in the extraction operation can be appropriately changed depending on the properties of the degassed oil of the vacuum distillation residue as the raw material oil, in particular, the aromatic compound content and the polycyclic aromatic compound content. It is preferably selected in the range of 125 ° C., tower bottom temperature of 50 to 85 ° C., and solvent ratio of 1.0 to 5.0.
[0022]
Naturally, the vacuum distillation residue changes its properties depending on the type of crude oil and the severity of the vacuum distillation, and therefore the devolatilized oil also changes its physical properties and chemical composition.
[0023]
The factor that determines the extraction operation conditions of the present invention is the chemical composition of the decoction oil used as a raw material. First, if the aromatic compound content of the decoction oil is low, the extraction operation conditions are milder, that is, the above extraction conditions. In the range, the extraction temperature at the top of the tower can be lowered and the solvent ratio can be lowered to select the conditions for keeping the yield of the extracted oil low, and the aromatic carbon content (Ca%) of the resulting extracted oil can be increased. . On the other hand, if the aromatic compound content of the decoction oil is high, the extraction operation conditions are severe, that is, the extraction temperature is increased and the solvent ratio is increased to increase the extraction oil yield. The carbon content (Ca%) can be adjusted.
[0024]
Also, if the PCA content of the desiccant oil is high, the extraction conditions are severe, that is, the extraction temperature is increased and the solvent ratio is increased to increase the extraction oil yield, thereby reducing the PCA content of the extracted oil. Adjust to suppress. Thus, the tower top temperature is preferably in the range of 90 to 125 ° C, more preferably in the range of 100 to 120 ° C.
[0025]
The temperature at the top of the column is an important factor that determines the amount dissolved in the extraction operation and the polarity of the fraction to be dissolved, that is, the solubility in the solvent, and at 125 ° C. or higher, not only aromatic compounds but also non-aromatic compounds. The dissolved amount is also increased, and it is difficult to achieve an aromatic carbon content of 30% or more of the extracted oil to be supplied to the next hydrorefining, and at 90 ° C. or less, an aromatic similar in polarity to the polycyclic aromatic compound. Since the compound is mainly dissolved, it becomes difficult to reduce the PCA content of the extracted oil to be supplied to the next hydrorefining to 8% or less. As a result, in the next hydrorefining, the aromatic carbon content is 26 It is difficult to produce a non-carcinogenic useful aromatic hydrocarbon oil having a PCA content of 3% or less and a PCA content of 3% or less. Therefore, the tower top temperature is in the range of 90 to 125 ° C, preferably in the range of 100 to 120 ° C.
[0026]
The temperature at the bottom of the column is the difference between the temperature at the top of the column and the solute internal recirculation, that is, the product dissolved in the solvent at the top of the column elutes at a lower temperature at the bottom of the column, and is extracted by circulating in the column. It is an important factor for solute selectivity.
[0027]
In this sense, it is advantageous to adopt a lower temperature at the bottom of the tower and take a larger temperature gradient from the top of the tower. However, if the temperature gradient is too large, the internal circulation becomes too large, causing flooding and other phenomena. This is a problem that the extraction operation cannot be performed.
[0028]
In the extraction operation of the present invention, the extraction operation was most stably achieved when the temperature gradient from the top of the column was 30 to 40 ° C. Therefore, it is preferable that the tower bottom temperature is applied in a range of 50 to 85 ° C. in correlation with the tower top temperature, that is, a temperature gradient of 30 to 40 ° C.
[0029]
The ratio of the solvent flow rate to the raw material flow rate is called the solvent ratio, which is an important factor for determining the extraction dissolution amount together with the extraction temperature.
[0030]
The solvent ratio is in the range of 1.0 to 5.0, preferably 1.5 to 4.0. If the solvent ratio is less than 1.0, the polycyclic aromatic compound of the desiccated oil and the aromatic compound having a polarity similar to that dissolve mainly, and the PCA content of the extracted oil can be reduced to 8% or less. If it exceeds 5.0, the amount of dissolved not only aromatic compounds but also non-aromatic compounds will increase, making it difficult to achieve an aromatic oil content of 30% or more in the extracted oil, and a large amount of solvent. Extra energy is required for recovery, which is disadvantageous in process cost. Therefore, the solvent ratio is preferably 1.0 to 5.0, and more preferably 1.5 to 4.0.
[0031]
In this way, by selecting appropriate extraction conditions depending on the properties of the deodorized oil, the carbon content of the aromatic compound formed by the composition analysis method defined in ASTM D 2140 is 30% or more and the polycyclic aroma is determined by the IP346 test method. Extracted oil with a group compound content, that is, PCA of 8% or less is obtained. This property of the extracted oil is obtained by subjecting the extracted oil to an aromatic carbon content of 26% or more and a PCA content under mild reaction conditions of relatively low pressure to medium pressure and relatively low temperature to medium temperature. It is an essential requirement of the present invention to finish an aromatic hydrocarbon oil of less than 3%.
[0032]
Oil hydrorefining is a widely practiced process in the oil refining industry. The purpose of hydrorefining is broad and its embodiment is mainly a hydrocracking method of relatively high temperature and high pressure mainly applied to the production of light fuel oil, hydrodesulfurization method mainly for removing sulfur content of fuel oil, mainly lubrication Applicable to the removal of aromatics from oil fractions by hydrogenation at relatively high temperatures and pressures, mainly for color finishing and stability improvement by hydrogenation of labile substances such as olefins in lubricating oil fractions. A hydrothermal dewaxing method that selectively hydrocracks wax in liquid hydrocarbons, such as hydrofinishing at a relatively low temperature and low pressure.
[0033]
The hydrorefining of the extracted oil of the present invention can be technically facilitated by applying mild reaction conditions of relatively low pressure to medium pressure and relatively low temperature to medium temperature so as to facilitate the process cost. It is designed strictly in correlation with the oil extraction process.
[0034]
In other words, the aromatic carbon content and PCA content of the extracted oil provided as a raw material are realized by limited extraction operation, and the polycyclic aromatic compound is hydrogenated and hydrocracked, and the non-polycyclic aroma of the raw oil is obtained. Group compounds are embodied by hydrotreating under mild reaction conditions that do not excessively hydrogenate or hydrocrack.
[0035]
In order to apply this relatively mild hydrogenation condition, the catalyst used in the present invention is preferably one or more metal oxide catalysts of iron, cobalt, nickel and molybdenum supported on an inorganic oxide support. Used. The supported amount of these metal oxides is preferably 23% by weight or more based on the total weight of the catalyst.
[0036]
Petroleum hydrogenation is a competitive reaction between the decomposition of the inorganic oxide carrier due to the acid point and the hydrogenation with the supported metal. By adjusting the amount of metal supported on the catalyst, the hydrogenation reaction can be carried out sufficiently under mild reaction conditions. Can proceed. If the amount of metal oxide supported is less than 23% by weight, the decomposition reaction due to the acidic point of the support is excellent, and catalyst deactivation such as carbonaceous deposition on the catalyst is undesirable.
[0037]
As the inorganic oxide carrier, alumina, silica, zeolite, aluminosilicate, clay and the like are used, but not limited thereto. A mixture of silica and alumina is particularly preferred as the support.
[0038]
The catalyst is vulcanized and activated by a petroleum feedstock with a high sulfur content, such as a vacuum straight cut of petroleum, or a liquid sulfur compound, such as carbon disulfide.
[0039]
The reaction temperature is suitably in the range of 280 to 360 ° C, preferably in the range of 300 to 340 ° C. Excessive reaction temperature causes not only hydrogenation and hydrogenolysis of the starting polycyclic aromatic compound, but also hydrogenation and hydrogenolysis of useful non-polycyclic aromatic compounds, resulting in aromatic hydrocarbons This is not preferable because the aromatic carbon content of the oil cannot be maintained at 26% or more. Furthermore, excessive temperatures will cause deactivation of the raw materials and carbonaceous deposition on the catalyst, so temperatures exceeding 360 ° C. should not be used.
[0040]
The reaction temperature is preferably 280 ° C. or higher. When the temperature is lower than 280 ° C., the hydrogenation and hydrocracking reaction of the polycyclic aromatic compound of the raw material extracted oil does not proceed sufficiently, and as a result, it becomes impossible to obtain an aromatic hydrocarbon oil having a PCA of 3% or less.
[0041]
If the polycyclic aromatic compound, that is, the PCA content of the feedstock exceeds 8%, the PCA content of the resulting aromatic hydrocarbon oil cannot be reduced to less than 3% within this temperature range. It is an essential requirement of the present invention to adjust the PCA content of the oil to 8% or less in the previous extraction step.
[0042]
The smaller the PCA content of the raw material extracted oil, the milder the hydrorefining conditions, and the better the hydrogenation and hydrocracking of non-polycyclic aromatic compounds. The PCA content and aromatic carbon content of the extracted oil are not unambiguous but fluctuate in a correlated manner, that is, when an extract oil with a lower PCA content is obtained, the aromatic carbon content is also lower. Aromatic carbon content of 30% or more cannot be maintained, and it is impossible to obtain an aromatic hydrocarbon oil having an aromatic carbon content of 26% or more from such raw material oil under this reaction temperature condition. It is hard to do. Therefore, in the extraction operation prior to hydrorefining, it is an essential requirement of the present invention to adjust the extracted oil having a PCA content of 8% or less and an aromatic carbon content of 30% or more.
[0043]
The hydrogen pressure of the reaction is preferably in the range of 40 to 90 kg / cm2. In this range, selective hydrogenation and hydrocracking of the polycyclic aromatic compound of the adjusted raw material extract oil of the present invention is achieved, and excessive hydrogenation and hydrocracking of the non-polycyclic aromatic compound is achieved. Can be suppressed.
[0044]
When the pressure is less than 40 kg / cm 2, the hydrogenation and hydrocracking reaction of the polycyclic aromatic compound of the feedstock does not proceed sufficiently, and as a result, it is difficult to obtain an aromatic hydrocarbon oil having a PCA content of less than 3%. Become. Furthermore, since the hydrogenation reaction is not sufficiently achieved, the raw material oil is decomposed and the carbonaceous deposits on the catalyst are caused, resulting in deactivation of the catalyst. At 90Kg / cm2 pressure, hydrogenation and hydrocracking of non-polycyclic aromatic compounds in the feedstock will result, making it difficult to obtain useful aromatic hydrocarbon oils with an aromatic carbon content of 26% or more. Become.
[0045]
The raw material flow rate supplied to the reaction tower is a space velocity based on the amount of the packed catalyst, and is preferably in the range of 0.5 to 3.0 LHSV. In this range, along with the above reaction conditions, selective hydrogenation and hydrocracking of the polycyclic aromatic compound of the conditioned raw material extraction oil of the present invention is achieved, and excessive non-polycyclic aromatic compound excess is achieved. Hydrogenation and hydrocracking can be suppressed.
[0046]
If the space velocity is less than 0.5 LHSV, the hydrogenation and hydrocracking reaction proceeds too much, and not only the removal of the polycyclic aromatic compound but also the non-polycyclic aromatic compound is hydrogenated and hydrocracked. It becomes difficult to obtain a useful aromatic hydrocarbon oil having a group carbon content of 26% or more. Further, when the space velocity exceeds 3.0 LHSV, the contact efficiency of the feedstock with the catalyst surface is drastically lowered, so that the hydrogenation and hydrocracking reaction of the polycyclic aromatic compound of the feedstock does not proceed, resulting in the polycyclic aroma. It becomes difficult to obtain a useful aromatic hydrocarbon oil having a group compound content, that is, a PCA content of less than 3%.
[0047]
The ratio of the hydrogen flow rate to the feed oil flow rate is not a limiting requirement in the present invention, but is preferably in the range of 200 to 600 sM3 / Kl. If the hydrogen flow rate is lower than 200 sM3 / Kl, the carbon deposition on the catalyst cannot be suppressed and catalyst deactivation is promoted, so that the catalyst life is shortened. If it exceeds 600 sM3 / Kl, too much hydrogen is not involved in the reaction. The process cost is disadvantageous.
[0048]
The refined oil of the present invention that has undergone hydrorefining treatment is finally hydrotreated by removing a very small amount of light cracked oil produced by low-level hydrocracking that is accompanied by hydrorefining in a light oil stripping tower. Product, that is, aromatic hydrocarbon oil.
[0049]
The thus obtained petroleum aromatic hydrocarbon oil having an aromatic carbon content of 26% or more and a PCA content of less than 3% according to the present invention is equivalent to a rubber process oil or an ink compounding agent conventionally used. It is a non-carcinogenic petroleum-based aromatic hydrocarbon oil that has the following performance and is safe and does not pollute the environment.
[0050]
In particular, when the aromatic carbon content is 26% or more, if it is less than 26%, the compatibility and affinity with the rubber are insufficient, causing the physical properties of the rubber product using it, particularly the tensile strength and elongation to be reduced. This is an essential requirement for the aromatic hydrocarbon oil of the present invention in that it bleeds when the amount is increased.
[0051]
Examples of the present invention are shown below. The invention will be more clearly explained and fully understood by means of the following examples of data obtained from operating conditions showing more prominent features of the invention and data presented as comparative examples.
However, the present invention is not limited to these examples.
[0052]
【Example】
[Table 1]

Table 1 shows the properties of the feed oil used in the present invention. The defragmentation oil used as the feedstock varies depending on the type of crude oil, the severity of the distillation refining method, and the conditions of the defragmentation operation, and its properties are not limited to these two types, but are representative of them.
The property value of the feedstock is 5. JIS K 2249 (crude oil and petroleum products-density test method and density / mass / volume conversion table). Vibration density test method, viscosity is JIS K 2283 (crude oil and petroleum products-kinematic viscosity test method and viscosity index calculation method), refractive index is JIS C 2101 (electric insulation oil test method) 14.4 Abbe refractometer The aniline point was measured by JIS K 2256 (Petroleum product aniline point and mixed aniline point test method).
[0053]
[Table 2]

Table 2 shows the results of the extraction process of the present invention.
In Example 1, the oil A was used as the raw material oil, and the extraction process was carried out at a furfural as a solvent, a tower top temperature of 102 ° C., a tower bottom temperature of 67 ° C., and a solvent ratio of 1.8 to obtain an aromatic carbon content (Ca %) Was obtained as an extracted oil having 36.0% and a PCA content of 4.2%.
In Example 2, the base oil A was used as the base oil and extracted as phenol with a solvent of phenol, a tower top temperature of 115 ° C., a tower bottom temperature of 76 ° C., and a solvent ratio of 2.7 to obtain an aromatic carbon content (Ca% ) Was 34.0%, and an extracted oil having a PCA content of 6.7% was obtained.
In Example 3, the base oil B was used as the base oil, and the extract was treated with furfural as a solvent at a tower top temperature of 108 ° C., a tower bottom temperature of 72 ° C., and a solvent ratio of 3.2. %) Was 35.0%, and an extracted oil having a PCA content of 5.8% was obtained.
[0054]
[Table 3]

Table 3 shows the results of the extraction process not according to the present invention.
In Comparative Examples 1 to 3, if any one of the extraction conditions according to the present invention, that is, the column top temperature of 90 to 125 ° C., the column bottom temperature of 50 to 85 ° C., and the solvent ratio of 1.0 to 5.0 is removed, the aromatic carbon Even if the content of 30% or more or PCA content of 8% or less can be satisfied, the intermediate to be supplied to the next hydrorefining step having an aromatic carbon content of 30% or more and PCA content of 8% or less I can't get oil.
[0055]
[Table 4]

Table 4 shows the results of hydrorefining according to the present invention, and the product shows an aromatic hydrocarbon oil obtained by stripping a very small amount of light cracked oil produced by hydrorefining.
In Example 4, the extracted oil obtained in Example 1 was subjected to a hydrogenation process at a hydrogen pressure of 70 kg / cm 2, a reaction temperature of 320 ° C., a raw material flow rate of 1.0 LHSV, and a hydrogen flow rate of 400 GHSV. An aromatic hydrocarbon oil having a content of 32.5% and a PCA content of 2.2% could be obtained.
In Example 5, the extracted oil obtained in Example 1 was subjected to hydrogenation treatment at a hydrogen pressure of 45 kg / cm 2, a reaction temperature of 340 ° C., a raw material flow rate of 0.8 LHSV, and a hydrogen flow rate of 500 GHSV. An aromatic hydrocarbon oil having a content of 31.0% and a PCA content of 2.4% could be obtained.
In Example 6, the extracted oil obtained in Example 2 was subjected to a hydrogenation process at a hydrogen pressure of 90 kg / cm 2, a reaction temperature of 340 ° C., a raw material flow rate of 1.5 LHSV, and a hydrogen flow rate of 600 GHSV. An aromatic hydrocarbon oil having a content of 30.5% and a PCA content of 1.8% could be obtained.
In Example 7, the extracted oil obtained in Example 3 was subjected to hydrogenation treatment at a hydrogen pressure of 80 kg / cm 2, a reaction temperature of 360 ° C., a raw material flow rate of 2.0 LHSV, and a hydrogen flow rate of 500 GHSV. An aromatic hydrocarbon oil having a content of 31.5% and a PCA content of 2.9% could be obtained.
[0056]
[Table 5]

Table 5 shows the results of hydrorefining not according to the present invention, and the product shows an aromatic hydrocarbon oil obtained by stripping a very small amount of light oil produced by hydrorefining.
Comparative Examples 4 to 6 show the results of using the intermediate oil obtained by the extraction operation according to the present invention as a raw material and applying hydrorefining conditions under conditions not according to the present invention. As a result, even when the extracted oil according to the present invention is used as a raw material, the hydrorefining conditions according to the present invention, that is, the reaction temperature of 280 to 360 ° C., the hydrogen pressure of 40 to 90 Kg / cm 2, and the raw material space velocity of 0.5 to 3.0 LHSV. However, if it deviates, it shows that a useful non-carcinogenic aromatic hydrocarbon oil having an aromatic carbon content of 26% or more and a PCA content of less than 3% cannot be obtained.
Comparative Examples 7 to 9 show the results of applying hydrorefining conditions under the conditions of the present invention using an intermediate oil obtained by an extraction operation not according to the present invention as a raw material. As a result, when the extracted oil not according to the present invention is used as a raw material, the hydrorefining conditions according to the present invention, that is, the reaction temperature of 280 to 360 ° C., the hydrogen pressure of 40 to 90 kg / cm 2, and the raw material space velocity of 0.5 to 3.0 LHSV are obtained. Even if applied, it shows that a useful non-carcinogenic aromatic hydrocarbon oil having an aromatic carbon content of 26% or more and a PCA content of less than 3% cannot be obtained.
[0057]
[Table 6]

[Table 7]

Table 6 shows the results obtained by examining the aromatic hydrocarbon oil obtained by the present invention as a process oil for rubber.
Table 7 shows the results of study on aromatic hydrocarbon oils not according to the present invention and conventionally used process oils for aromatic rubbers.
[0058]
The rubber composition used in the examination is the standard composition table No. JIS K 6383 (Testing method for synthetic rubber SBR) used for examination of compounding materials such as raw rubber, carbon black and process oil. The blending system according to the blending for non-oiled rubber 1 was used, and the kneading method using a rubber blending roll was also carried out by the method described in the test method. Vulcanization conditions were determined from the results of measurement with a Japanese synthetic rubber curast meter, and vulcanized with a press vulcanizer.
The physical properties of the product are measured by JIS K 6301 (vulcanized rubber physical test method) for hardness, JIS K 6251 (tensile test method for vulcanized rubber) for tensile strength and 300% tensile stress and elongation, and JIS K 6252 for tear strength. (Tearing test method for vulcanized rubber) and oil bleeding were performed by visual inspection after standing at room temperature for 48 hours.
[0059]
Examples 8 and 9 are the examination results of the aromatic hydrocarbon oil according to the present invention, and it was confirmed that the product physical properties were completely inferior to those of the commercially available process oil of Comparative Example 10.
Comparative Example 11 is a result of the investigation of hydrocarbon oils not according to the present invention. Compared with the result of the commercially available process oil of Comparative Example 10, the tensile strength and the elongation are extremely poor, and the oil containing 20 parts of process oil is used. Bleed was observed and it was confirmed that it was unbearable.
[0060]
【The invention's effect】
Since the present invention is configured as described above, the following effects can be obtained.
The present invention is a non-carcinogenic petroleum aromatic carbonization having performance equivalent to that of a petroleum aromatic hydrocarbon oil containing a carcinogenic polycyclic aromatic compound conventionally used as a process oil for rubber. The present invention provides a method for producing hydrogen oil easily and economically advantageously from degassed oil obtained by distillation of petroleum under reduced pressure by design of relative strict operating conditions for solvent extraction and hydrorefining.
[0061]
[Brief description of the drawings]
FIG. 1 is a process diagram according to the present invention.
[Explanation of symbols]
1 Extraction tower solvent line
2 Extraction tower feed oil line
3 Extraction tower extraction residual oil
4 Extraction tower extraction oil line
5 Hydrorefining product line
6 Lightly decomposed oil
7 Aromatic hydrocarbon oil
8 Heat exchanger
9 Extraction tower
10 Hydrorefining tower
11 Light cracked oil stripping tower

Claims

Carbon content of 30% or more forming an aromatic compound by the composition analysis method defined in ASTM D 2140 by solvent extraction treatment from the debris oil obtained from petroleum-based vacuum distillation residue, polycyclic aromatic by IP346 test method An extracted oil having a compound content of 8% or less is obtained and obtained by subjecting the extracted oil to a hydrogenation reaction at a reaction temperature of 280 to 360 ° C., a hydrogen pressure of 40 to 90 kg / cm 2, and a raw material space velocity of 0.5 to 3.0 LHSV. A non-carcinogenic aromatic hydrocarbon oil having a carbon content of 26% or more forming an aromatic compound specified in ASTM D 2140 and a polycyclic aromatic compound content of less than 3% according to the IP346 test method. How to manufacture.

The solvent used for the solvent extraction treatment of the decoction oil is one kind of solvent selected from polar solvents such as furfural, phenol and n-methylpyrrolidone, or a mixed solvent of two or more kinds. The method of claim 1.

The solvent extraction process of the debris oil is performed at a tower top temperature of 90 to 125 ° C., a tower bottom temperature of 50 to 85 ° C., and a solvent ratio of 1.0 to 5.0 using a countercurrent contact type extraction tower. The method according to claim 1 or 2.

The hydrogenation reaction of the extracted oil is performed by using one or more metal oxide catalysts of iron, cobalt, nickel and molybdenum supported on an inorganic oxide. 4. The method according to any one of items 3.

The method according to claim 4, wherein the total weight of the metal oxide supported on the catalyst is 23% or more of the total weight of the catalyst.