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

نوع مقاله: علمی 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
[1] Mazzieri V. A., Pieck C. L., Vera C. R., Yori J. C., Grau J. M., Analysis of Coke Deposition and Study of the Variables of Regeneration and Rejuvenation of Naphtha Reforming Trimetallic Catalysts, Catalysis Today, Vol. 133, 2008, pp 870-878.

[2] Vadi M., Hosseinzade A., Catalytic Reforming of n-Heptane on Platinum-Palladium Supported on γ-Alumina, Asian Journal of Chemistry, Vol. 22, 2010, p 6640.

[3] Pieck C. L., Vera C. R., Parera J. M., Giménez G. N., Serra L. R., Carvalho L. S., Rangel M. C., Metal Dispersion and Catalytic Activity of TrimetallicPt-Re-Sn/Al2O3Naphtha Reforming Catalysts, Catalysis Today, Vol. 107, 2005, pp 637-642.

[4] Carnevillier C., Epron F., Marecot P., Controlled Preparation and Characterization of PlurimetallicPt–Sn and Pt–Ir–Sn/Al2O3 Reforming Catalysts, Applied Catalysis A: General, Vol. 275, 2004, pp 25-33.

[5] Castellazzi P., Groppi G., Forzatti P., Effect of Pt/PdRatio on Catalytic Activity and Redox Behavior of Bimetallic Pt–Pd/Al2O3Catalysts for CH4Combustion, Applied Catalysis B: Environmental, Vol. 95, 2010, pp 303-311.

[6] Boutzeloit M., Benitez V. M., Mazzieri V. A., Especel C., Epron F., Vera C. R., Pieck C. L., Marécot P., Effect of the Method of Addition of Ge on the Catalytic Properties of Pt–Re/Al2O3 and Pt–Ir/Al2O3 Naphtha Reforming Catalysts, Catalysis Communications, Vol. 7, 2006, pp 627-632.

[7] Toledo J. A., Bokhimi X., Lopez C., Angeles C., Hernandez F., Fripiat J. J., Synthesis of Highly Porous Aluminas Mediated by Cationic Surfactant: Structural and Textural Properties, Journal of Materials Research, Vol. 20, 2005, pp 2947-2954.

[8] Hamoule T., Peyrovi M. H., Rashidzadeh M., Toosi M. R., Catalytic Reforming of n-Heptane over Pt/Al-HMS Catalysts, Catalysis Communications, Vol. 16, 2011, pp 234-239.

[9] Peyrovi M. H., Hamoule T., Sabour B., Rashidzadeh M., Synthesis, Characterization and Catalytic Application of Bi-and TrimetallicAl-HMS Supported Catalysts in Hydroconversionof n-Heptane, Journal of Industrial and Engineering Chemistry, Vol. 18, 2012, pp 986-992.

[10] Martin N., Viniegra M., Zarate R., Espinosa G., BatinaN., Coke Characterization for an Industrial Pt–Sn/γ-Al2O3Reforming Catalyst, Catalysis Today, Vol. 107, 2005, pp 719-725.

[11] Martin N., Viniegra M., Lima E., Espinosa G., Coke Characterization on Pt/Al2O3-β-Zeolite Reforming Catalysts, Industrial &Engineering Chemistry Research, Vol. 43, 2004, pp 1206-1210.

[12] Bowker M., Aslam T., Roebuck M., Moser M., The Effect of Coke Lay-Down on n-Heptane Reforming on Pt and Pt-SnCatalysts, Applied Catalysis A: General, Vol. 257, 2004, pp57-65.

[13] Baghalha M., Mohammadi M., Ghorbanpour A., Coke Deposition Mechanism on the Pores of a Commercial Pt–Re/γ-Al2O3Naphtha Reforming Catalyst, Fuel Processing Technology, Vol. 91, 2010, pp714-722.

[14] Martins A., Silva J. M., Henriques C., Ribeiro F. R., Ribeiro M. F., Influence of Rare Earth Elements La, Nd and Yb on the Acidity of H-MCM-22 and H-Beta Zeolites, Catalysis Today, Vol. 107, 2005, pp 663-670.

[15] de la Puente G., Souza-Aguiar E. F., Zotin F. M. Z., Camorim V. L. D., Sedran U., Influence of Different Rare Earth Ions on Hydrogen Transfer over Y Zeolite, Applied Catalysis A: General, Vol. 197, 2000, pp 41-46.

[16] Yamamoto T., Tanaka T., Matsuyama T., Funabiki T., Yoshida S., Alumina-Supported Rare-Earth Oxides Characterized by Acid-Catalyzed Reactions and Spectroscopic Methods, The Journal of Physical Chemistry B, Vol. 105, 2001, pp 1908-1916.

[17] Peyrovi M. H., Parsafard N., Peyrovi P., Influence of Zirconium Addition in Platinum–Hexagonal Mesoporous Silica (Pt-HMS) Catalysts for Reforming of n-Heptane, Industrial & Engineering Chemistry Research, Vol. 53, 2014, pp 14253-14262.

[18] Yang X., Liao S., Zeng J., Liang Z., A Mesoporous Hollow Silica Sphere (MHSS): Synthesis Through a Facile Emulsion Approach and Application of Support for High Performance Pd/MHSS Catalyst for Phenol Hydrogenation, Applied Surface Science, Vol. 257, 2011, pp 4472-4477.

[19] Posada J. A., Cardona C. A., Giraldo O., Comparison of Acid Sulfonic MesostructuredSilicas for 1-Butylacetate Synthesis, Materials Chemistry and Physics, Vol. 121, 2010, pp 215-222.