بررسی نشست کک روی کاتالیستهای ریفورمینگ: اثر افزایش نئودیمیم و سرب به پلاتین

نوع مقاله : ترویجی

نویسندگان

هیئت علمی

چکیده

در این مقاله، جزئیات فعالیت کاتالیستی واکنش ریفورمینگ نرمال‌هپتان و اثر پارامترهای مختلف نظیر دما (°C 500-450)، فشار (atm 30-15)، اثر بهبود دهندگی فلزات مختلف (نئودیمیوم و سرب) و مقدار آنها بر روی این واکنش و همچنین مقدار کک تشکیل شده بر سطح کاتالیستها بررسی شده است. مقدار کک تشکیل شده بر سطح این کاتالیستها با استفاده از روش وزن‌سنجی حرارتی (TG/DTA) مورد مطالعه قرار گرفت. نتایج نشان می‌دهند که تشکیل کک بر روی کاتالیستهای دو فلزی Pt-(Pb, Nd)/γ-Al2O3 کمتر از کاتالیستهای تک فلزی می‌باشد. علاوه بر این، کاتالیستهای دو فلزی فعالیت بالایی را هم در این واکنش نشان می‌دهند.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Study of Coke Deposition on Reforming Catalysts: Influence of the Addition of neodymium and lead to Platinum

نویسنده [English]

  • Nastaran Parsafard
چکیده [English]

In this paper, the details of catalytic activity for the reforming reaction of normal heptane and the effect of different parameters such as temperature (450-500 °C), pressure (15-30 atm), promoting effect of various metals (neodymium and lead) and their amounts on this reaction and also the amount of formed coke on catalyst surface was investigated. The amount of formed coke on the surface of these catalysts was studied by thermal gravimetric (TG/DTA) method. The results show that the formation of coke on bimetallic catalysts of Pt-(Pb, Nd)/γ-Al2O3 are lower than the monometallic catalysts. Furthermore, the bimetallic catalysts also show the high activity in this reaction.

کلیدواژه‌ها [English]

  • Reforming
  • Coke
  • Monometallic catalysts
  • Bimetallic catalysts
  • Neodymium
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