بهبود فعالیت و افزایش مقاومت مکانیکی کاتالیست واکنش تبدیل آب-گاز دما بالا

نوع مقاله : ترویجی

نویسندگان

1 دانشجوی کارشناسی ارشد مهندسی شیمی گرایش ترمو سینتیک و کاتالیست دانشگاه صنعتی شریف

2 دانشیار دانشگاه صنعتی شریف دانشکده مهندسی شیمی و نفت

3 عضو گروه تحقیقاتی کاتالیست شرکت پژوهش و فناوری پتروشیمی مرکز تهران

چکیده

واکنش تبدیل آب-گاز به عنوان مرحله‌ای کلیدی در واحدهای صنعتی تولید هیدروژن به‌کارمی‌رود. در این پژوهش کاتالیست‌های Fe/Cr/Cu که در واکنش تبدیل آب-گاز دما بالا مورد استفاده قرار می‌گیرد، به منظور بهبود عملکرد به روش هم‌رسوبی و با پیش‌سازنده‌های سولفات ساخته شده‌اند و تمرکز اصلی بر تاثیر زمان پیرسازی بر فعالیت و مقاومت مکانیکی می‌باشد. کاتالیست‌های ساخته شده، تحت آزمون راکتوری (در دمای oC 360 و فشار 2 بار) و آزمون‌های تعیین مشخصات BET، XRD، TPR و سختی‌سنج قرص با نمونه‌های صنعتی مورد مقایسه قرار گرفتند. افزایش زمان پیرسازی، منجر به کاهش کلوخه شدن و سطح ویژه و افزایش مقاومت مکانیکی کاتالیست‌ها می‌گردد. کاتالیست‌های تهیه شده در زمان پیرسازی 180 و 270 دقیقه به ترتیب با میزان تبدیل %50/5 و %46/5 در انتهای واکنش و قدرت مکانیکی kg/pellet 4/46 و kg/pellet  4/53 نسبت به سایر نمونه‌ها و کاتالیست صنعتی، عملکرد مناسبی را نشان داده‌اند.

کلیدواژه‌ها


عنوان مقاله [English]

Activity development and increasing the mechanical strength of high temperature water-gas shift catalyst

نویسندگان [English]

  • Farzad Haghighi 1
  • Morteza Baghalha 2
  • mohsen bahmani 3
1 Student, Sharif University of Technology, Tehran, Iran
2 Associate professor, Sharif upstream petroleum research institute, Tehran, Iran
3 Catalysis Research Group, Petrochemical Research and Technology Company NPC, Tehran, Iran
چکیده [English]

Water-gas shift reaction is performed as the key step in the hydrogen industrial plant. In this work, Fe/Cr/Cu high temperature water gas shift catalysts were synthesized by co-precipitation method, using sulfate precursors, in order to improve the catalytic performance and particular emphasis is placed on the mechanical strength and catalytic activity affected by aging time. The prepared and industrial catalysts were compared when they were situated in the operating conditions (at 360oC and 2 bar) and were characterized by BET, XRD, TPR and crushing strength analysis. Increasing the aging time leads to decrease the sintering and specific surface area and increase the mechanical strength of the catalysts. The catalysts prepared with 180 and 270 minutes aging time were shown, 50.5% and 46.5% conversion and 4.46 kg/pellet and 4.53 kg/pellet mechanical strength respectively, that have appropriate performance in comparison with other prepared samples and commercial catalyst.

کلیدواژه‌ها [English]

  • Water Gas Shift Catalyst
  • Mechanical Strength
  • Aging Time
  • Catalytic activity
[1] Callaghan, Caitlin A. “Kinetics and catalysis of the water-gas-shift reaction: A microkinetic and graph theoretic approach”. Diss. Naval Undersea Warfare Center, 2006.
[2] Ratnasamy C. Wagner J.P. “Water Gas Shift Catalysis”. Catalysis Reviews, Vol. 51, 2009, pp. 325-440.
[3] Sunggyu, Lee. "Encyclopedia of chemical processing. Edn. 3. Vol. I.", 2005: 31-3.
[4] RJ Smith B., Loganathan M., Shantha M.S., (2010), a review of water-gas shift reaction kinetics, International Journal of Chemical Reactor Engineering, Vol. 8, pp. 2-32.
[5] Mendes, D., et al. "The water‐gas shift reaction: from conventional catalytic systems to Pd‐based membrane reactors—a review." Asia‐Pacific Journal of Chemical Engineering 5.1, 2010, pp. 111-137.
[6] Zhu, Minghui, and Israel E. Wachs. "Iron-Based Catalysts for the High-Temperature Water–Gas Shift (HT-WGS) Reaction: A Review." ACS Catalysis 6.2, 2015, pp. 722-732.
[7] Scariot, Morgana, et al. "An investigation of the activation process of high temperature shift catalyst." Catalysis Today 133, 2008, pp. 174-180.
[8] Rhodes, C., Hutchings, G.J. and Ward, A.M. “Water-gas shift reaction: finding the mechanistic boundary”. Catalysis Today. Vol. 23, 1995, pp. 43-58.
[9] Li, Yongdan, et al. "Effect of abnormal treatment on the mechanical strength of iron-based high-temperature shift catalyst." Applied Catalysis A: General 133.2, 1995, pp. 293-304.
[10] Li, Yongdan, et al. "The possibility of increasing the mechanical strength of Fe-based commercial WGS catalysts Factors analysis in the calcination process." Catalysis Today 30.1, 1996, pp. 49-57.
[11] Li, Yongdan, and Liu Chang. "Optimizing the mechanical strength of Fe-based commercial high-temperature water-gas shift catalyst in a reduction process." Industrial & engineering chemistry research 35.11, 1996, pp. 4050-4057.
[12] Li, Yongdan, Jiusheng Zhao, and Liu Chang. "Factors analysis for mechanical strength in pelleting process of Fe-based high temperature shift catalyst." Studies in Surface Science and Catalysis 63, 1991, pp. 145-153.
[13] Yakerson, V. I., and E. Z. Golosman. "Scientific bases for the preparation of new cement containing catalysts." Studies in Surface Science and Catalysis 91, 1995, pp. 879-884.
[14] Na, Hyun-Suk, et al. "The effect of preparation method on Fe/Al/Cu oxide-based catalyst performance for high temperature water gas shift reaction using simulated waste-derived synthesis gas." International Journal of Hydrogen Energy 40.36, 2015, pp. 12268-12274.
[15] Leofanti, G., et al. "Surface area and pore texture of catalysts." Catalysis Today 41.1, 1998, pp.207-219.
[16] Meshkani, Fereshteh, Mehran Rezaei, and Mohammad Jafarbegloo. "Preparation of nanocrystalline Fe2O3–Cr2O3–CuO powder by a modified urea hydrolysis method: A highly active and stable catalyst for high temperature water gas shift reaction." Materials Research Bulletin 64, 2015, pp. 418-424.
[17] Maroño, M., et al. "Performance of Fe–Cr based WGS catalysts prepared by co-precipitation and oxi-precipitation methods." international journal of hydrogen energy 34.21, 2009, pp. 8921-8928.
[18] Dufour, J., et al. "Effect of the precursor on the activity of high temperature water gas shift catalysts." International Journal of Hydrogen Energy 38.18, 2013, pp. 7647-7653.
[19] Meshkani, Fereshteh, and Mehran Rezaei. "A facile method for preparation of iron based catalysts for high temperature water gas shift reaction." Journal of Industrial and Engineering Chemistry 20.5, 2014, pp. 3297-3302.