گوگردزدایی اکسایشی ترکیبات تیوفنی با کاتالیست پایه دار پلی‌اگزومتال دووسون

نوع مقاله: مقاله پژوهشی

نویسندگان

دانشکده مهندسی شیمی، نفت و گاز، دانشگاه علم و صنعت ایران

چکیده

در این تحقیق به‌منظور حذف ترکیبات گوگردی مقاوم، با استفاده از روش اکسیداسیونی، کاتالیزوری جدید بر پایه نمک دووسون (H9P2W15V3O62) و با استفاده از روش سل ژل سنتز گردید. کاتالیزور پیشنهادی دارای ترکیب H9P2W15V3O62/TiO2 است. ساختار کاتالیزور و نمک با استفاده‌ از روش‌های تشخیصی FT-IRا، XRD و UV مورد ارزیابی قرار گرفت و عملکرد آن در فرآیند گوگردزدایی اکسایشی ترکیبات آروماتیکی بنزوتیوفن و دی‌بنزوتیوفن(از مقاوم‌ترین ترکیبات گوگردی در برابر اکسایش) مخلوط با نرمال اکتان، تحت شرایط عملیاتی متوسط (فشار اتمسفر و دمای زیر 70oC) مورد مطالعه قرار گرفت. نتایج آزمایش‌های راکتوری نشان می‌دهد که کاتالیست سنتز شده دارای عملکرد مناسب (دست‌یابی به درصد تبدیل 100% برای دی‌بنزوتیوفن و بیش از 78% برای بنزوتیوفن در مدت زمان hr 20) در گوگردزدایی اکسایشی است. شرایط فرآیندی(دما، مقدار کاتالیست و نسبت مولی اکسیژن به گوگرد) با استفاده از روش طراحی آزمایشات تاگوچی بهینه گردید. شرایط بهینه به‌صورت، دما oC 50 نسبت اکسیژن به گوگرد برابر 6 و مقدار کاتالیست g/L 5/7 به‌دست آمد.
 

کلیدواژه‌ها


عنوان مقاله [English]

Oxidative Desulfurization of Thiophenic Components by Dawson Polyoxometalate Supported Catalyst

نویسندگان [English]

  • Mosayeb Naderi Khomartaji
  • Mohammad Reza Dehghani
  • Farhad Banisharifdehkordi
Chemical Engineering Department, Iran University of Science and Technology, Tehran, Iran
چکیده [English]

In this work, a new catalyst based on Dawson salt, H9P2W15V3O62, is presented for oxidation of high stable sulfur compounds. The new catalyst, H9P2W15V3O62/TiO2, is synthesized by sol-gel method. The structure of catalyst and salt has been characterized by FT-IR, XRD and UV spectrophotometry. The performance of catalyst has been studied in the oxidative desulfurization of aromatic components, benzothiophene and dibenzothiophene (ones of the most resistant sulfuric components to oxidation), mixed with n-octane under mild operation conditions (temperature less than 70 oC and atmospheric pressure). The reactor tests’ results illustrated that the synthesized catalyst has a suitable performance (achieved 100% conversion of debenzothiophene and 78% conversion of benzothiophene in less than 20 minutes) in oxidative desulfurization. The process conditions (temperature, catalyst loading and a mole ratio of oxygen to sulfur) have been optimized by Taguchi Experimental Design method. Our results show that at 50 oC, the mole ratio of 6 for oxygen/sulfur and catalyst loading 7.5 g/L are optimum conditions.
 

کلیدواژه‌ها [English]

  • Oxidative Desulfurization
  • Thiophenic Component
  • Dawson Polyoxomatalate
  • Titania
  • Taguchi

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