ساخت زئولیت HZSM-5 در محیط حاوی یون فلوئورید و بررسی عملکرد آن در فرآیند تبدیل متانول به پروپیلن

نوع مقاله: مقاله پژوهشی

نویسندگان

1 دانشکده مهندسی شیمی و نفت، دانشگاه صنعتی شریف، تهران، ایران

2 شرکت پژوهش‌و فناوری‌پتروشیمی

چکیده

در این تحقیق زئولیت HZSM-5 در محیط حاوی یون فلوئورید ساخته شد و عملکرد آن در فرایند تبدیل متانول به پروپیلن مورد بررسی قرار گرفت. از نمک پتاسیم فلوئورید به عنوان ماده تأمین کننده این یون استفاده شد. خصوصیات فیزیکی-شیمیایی کاتالیست‌ها با استفاده از آنالیزهای XRD، FESEM، N2 Adsorption/Desorption وNH3-TPD شناسایی شدند. الگوی XRD تشکیل ساختار کریستالی مرتبط با زئولیت HZSM-5 را در زئولیت سنتز شده با پتاسیم فلوئورید (نمونه F-HZSM-5) تائید کرد. تصاویر FESEM زئولیت F-HZSM-5 تغییر در مورفولوژی و افزایش اندازه ذرات را در مقایسه با نمونه مرجع HZSM-5 نشان داد. نتایج آنالیز NH3-TPD کاهش غلظت کل مکان‌های اسیدی را در زئولیت F-HZSM-5 نشان داد. فعالیت نمونه‌ها در یک راکتور بستر ثابت و در شرایط عملیاتی یکسان بررسی شد. کاتالیست F-HZSM-5 نسبت به نمونه مرجع HZSM-5 طول عمر کمتری را نشان داد. با این حال، این کاتالیست در مدت 10 روز فعالیت به‌ترتیب متوسط انتخاب‌پذیری پروپیلن و نسبت پروپیلن به اتیلن 8/41 و 9/ 10 را داشته است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Construction of HZSM-5 Zeolite in Medium Containing Fluoride Ion and Its Performance in the Conversion of Methanol to Propylene

نویسندگان [English]

  • somayeh ahmadpour 1
  • Fereydoon Yaripour 2
  • Farhad Khorasheh 1
1 Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran
چکیده [English]

In this research, HZSM-5 zeolite was made in medium containing fluoride ions, and its performance in the process of methanol to propylene conversion was investigated. Potassium fluoride was used as the supplying material for this ion. Physical-chemical properties of catalysts were determined by using XRD, FESEM, N2 adsorption/desorption and NH3-TPD analysis. The XRD pattern confirmed the formation of crystalline structure associated with zeolite HZSM-5 in potassium fluoride-synthesized zeolite (F-HZSM-5 specimen). FESEM images of F-HZSM-5 zeolite showed a change in morphology and an increase in particles size compared to the reference sample HZSM-5. Results of the NH3-TPD analysis showed a reduction in the concentration of total acid sites in the F-HZSM-5 zeolite. The activity of the samples in a fixed-bed reactor and in the same operating conditions was investigated. The F-HZSM-5 catalyst showed less lifetime in comparison with the reference sample. However, this catalyst over a period of 10 days had an average selectivity of propylene and a propylene/ethylene ratio of 41.8 and 10.9, respectively.
 

کلیدواژه‌ها [English]

  • HZSM-5 zeolite
  • conversion of methanol to propylene
  • potassium fluoride
  • mineralizer

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