H2S’ÜN SEÇİCİ KATALİTİK OKSİDASYONU İLE ELEMENTEL KÜKÜRT ELDESİNDE Ce-O KATALİZÖRLERİ

Hacı Mehmet TAŞDEMİR, Yavuz Yağızatlı, Sena Yaşyerli, Nail Yaşyerli, Gülşen Doğu
114 20

Öz


Bu çalışmada, modifiye edilmiş kompleksleştirme yöntemi ile Ce-O katalizörleri hazırlanmış ve seçici katalitik oksidasyon ile elementel kükürt eldesindeki aktiviteleri araştırılmıştır. Katalizör sentezinin son basamağı olan kalsinasyon işlemi farklı sıcaklıklarda (300 oC, 350 oC, 400 oC ve 450 oC) gerçekleştirilerek kalsinasyon sıcaklığının katalitik aktiviteye etkisi incelenmiştir. Ce-O katalizörleriyle aktivite testleri 250oC sıcaklık ve farklı O2/H2S oranlarında sabit-yatak reaktör sisteminde gerçekleştirilmiştir. Farklı sıcaklıklarda kalsine edilen bütün katalizörlerin XRD desenlerinde yığın fazın “cerianite” kristal yapısında ve stokiyometrik olmayan oranda O2 bulundurduğu (CeO2-x) gözlenmiştir. Ce-O katalizörlerinin XPS analizi bu sonucu desteklemiş, katalizör yüzeyinde seryumun çoğunlukla +4 ve beraberinde +3 değerlikte bulunduğunu göstermiştir. Bütün Ce-O katalizörleri ile oldukça yüksek elementel kükürt seçiciliği (≥%97) elde edilmiştir. Bununla beraber, H2S seçici oksidasyonunda en uzun süre aktiviteyi (%69 H2S dönüşümü) 350 oC’da kalsine edilen Ce-O–350 katalizörü göstermiştir. Katalizörlerin kalsinasyon sıcaklığının düşmesi katalitik aktivitede yükselme ile sonuçlanmıştır. Kalsinasyon sıcaklığının düşmesi Ce-O katalizöründe oksijen hareketliliğini etkileyerek daha uzun süre katalitik aktivite göstermesine neden olmuştur. 


Anahtar kelimeler


Seryum oksit, H2S, Elementel kükürt, Seçici oksidasyon

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Referanslar


Zhang, X., Thang, Y., Qiao, N., Yang, L., Qu, S., Hao, Z. “Comprehensive study of H2S selective catalytic oxidation on combined oxides derived from Mg/Al-V10O28 layered double hydroxides”, Applied Catalysis B: Environmental, 176-177, 130-138, 2015.

Viet, C.D., Phouc, L.T., Thanh, T.T., Nhut, J.M., Dinh, L.N., Janowska, I., Begin, D., Huu, C.P. “Nitrogen-doped carbon nanotubes decorated silicon carbide as a metal-free catalyst for partial oxidation of H2S”, Applied Catalysis A: General, 482, 397-406, 2014.

Eslek, D.D., Yasyerli, S. “Selectivity and stability enhancement of iron oxide catalyst by ceria incorporation for selective oxidation of H2S to sulfur”, Industrıal &Engineering Chemistry Research, 48, 5223–5229, 2009.

Yasyerli, S., Dogu, G., Ar, I., Dogu, T. “Dynamic analysis of removal and selective oxidation of H2S to elemental sulfur over Cu-V and Cu-V-Mo mixed oxides in a fixed bed reactor”, Chemical Engineering Science, 59, 4001-4009, 2004.

Tasdemir, H.M., Yasyerli, S., Yasyerli, N. “Selective catalytic oxidation of H2S to elemental sulfur over titanium based Ti-Fe, Ti-Cr and Ti-Zr catalysts”, International Journal of Hydrogen Energy, 40, 9989-10001, 2015.

Uhm, J.H., Shin, M.Y, Zhidong, J.,Chung, J.S. “Selective oxidation of H2S to elemental sulfur over chromium oxide catalysts”, Applied Catalysis B: Environmental, 22, 293–303, 1999.

Laperdrix, E., Costentin, A., Saur, O., Lavalley, J.C.,Nedez, C., Poncet, S.S., Nougayrede, J. “Selective Oxidation of H2S over CuO/Al2O3: Identification and role of the sulfurated species formed on the catalyst during the reaction”, Journal of Catalysis, 189, 63–69, 2000.

Park, D.W.,Park, B-K.,Park, D-K., Woo, H-C. “Vanadium-antimony mixed oxide catalysts fort he selective oxidation of H2S containing excess water and ammonia”, Applied Catalysis A, 223, 215-224, 2002.

Davydov, A.A., Marshneva, V.I., Shepotko, M.L. “Metal oxides in hydrogen sulfide oxidation by oxygen and sulfur dioxide I. The comparison study of the catalytic activity. Mechanism of the interactions between H2S and SO2 on some oxides”, Applied Catalysis A: General, 244, 93–100, 2003.

Nguyen, P., Edouard, D., Nhut, J-M., Ledoux, M.J., Pham, Ch., Pham-Huu, C. “High thermal conductive -SiC for selective oxidation of H2S: A new support for exothermal reactions”, Applied Catalysis B: Environmental, 76, 300-310, 2007.

Shin, M.Y., Nam, C.M, Park, D.W., Chung, J.S. “Selective oxidation of H2S to elemental sulfur over VOx/SiO2 and V2O5 catalysts”, Applied Catalysis A: General, 211, 213–225, 2001.

Carmona, A.R., Soriano, M.D., Nieto, J.M.L., Jones, D.J., Jimenez, J.J., Lopez, A.J., Castellon, A.R. “Iron-containing SBA-15 as catalyst for partial oxidation of hydrogen sulfide”, Catalysis Today, 210,117–123, 2013.

Yasyerli, S., Dogu, G., Dogu, T. “Selective oxidation of H2S to elemental sulfur over Ce-V mixed oxide and CeO2 catalysts prepared by the complexation technique”, Catalysis Today, 117, 271-278, 2006.

Bineesh, K.V., Kim, S.Y., Cho, H.J., Park, D.W. “Synthesis of metal-oxide pillared montmorillonite clay for the selective catalytic oxidation of H2S”, Journal of Industrial and Engineering Chemistry, 16, 593–597, 2010.

Palma, V., Barba, D. “H2S purification from biogas by direct selective oxidation to sulfur on V2O5-CeO2 structured catalysts”, Fuel, 135, 99-104, 2014.

Aktas, O, Yasyerli,S, Dogu, G, Dogu, T,” Effect of Synthesis Conditions on the Structure and Catalytic Performance of V and Ce-Incorporated SBA-15-like Materials in Propane Selective Oxidation”, Industrıal &Engineering Chemistry Research, 49, 6790–6802, 2010.

Pantaleo, G, La Parola, V, Deganello, F, Singha, RK, Bal, R, Venezia, A.M,” Ni/CeO2 catalysts for methane partial oxidation: Synthesis driven structural and catalytic effects”, Applied Catalysis B: Environmental, 189, 233–241, 2016.

Paier, J., Penschke, J., Sauer, J., “Oxygen defect and surface chemistry of ceria: Quantum chemical studies compared to experiment”, American Chemical Society, 113, 3949-3985, 2013.

Kullgren, J, “Oxygen vacancy chemistry in ceria”, Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, 896, 2012.

Graciani, J, Marquez, AM, Plata, JJ, Ortega, Y, Hernandez, YC, Meyer, A, Zicowich-Wilson, CM, Sanz, JF,”Comparative study on the performance of hybrid DFT functionals in highly correlated oxides: The case of CeO2 and Ce2O3”, Journal of Chemical Theary and Computation, 7, 56-65, 2011.

Zhang, X., Dou, G., Wang, Z., Cheng, J.,Wang, H., Ma, C., Hao, Z. “Selective oxidation of H2S over V2O5 supported on CeO2-intercalated Laponite clay catalysts”, Catalysis Science Technology, 3, 2778, 2013.

Barba, D, Palma V, Ciambelli, P, “Screening of catalysts for H2S abatement from biogas to feed molten carbonate fuel cells, International Journal of Hydrogen Energy, 38, 328 -335, 2013.

Palma V, Barba, D,” Honeycomb V2O5-CeO2 Catalysts for H2S Abatement from Biogas by Direct Selective Oxidation to Sulfur at Low Temperature”, Chemical Engineering Transactions, 43, 1957-1962, 2015.

Park, N., Han, D.C., Han, G.B., Ryu, S.O., Lee, T.J., Yoon, K.J. “Development and reactivity tests of Ce-Zr-based Claus catalysts for coal gas cleanup”, Fuel, 86, 2232-2240, 2007.

Palma, V., Barba, D. “Low temperature catalytic oxidation of H2S over V2O5/ CeO2 catalysts”, International Journal of Hydrogen Energy, 39, 21524-21530, 2014.

Marcilly, C., Courty, P., Delmon, B. “Preparation of highly dispersed mixed oxides and oxide solid solutions by pyrolysis of amorphous precursors”, Journal of the American Ceramic Society, 53, 56-57, 1970.

Taşdemir, H.M., Yağızatlı, Y., Yaşyerli, S., Yaşyerli, N., Doğu, G., “H2S’ün seçici katalitik oksidasyonu için hazırlanan CeO2 katalizörünün kalsinasyon sıcaklığının aktiviteye etkisi”, 27. Ulusal Kimya Kongresi, Çanakkale, 23-28 Ağustos 2015.

Cullity, B.D., Stock, S.R. “Elements of X-rays Diffraction”, 3rd. Ed., Prentice Hall, NJ, USA, 2001.

Brundle, C.R., Evans, C.A. “Materials characterization series. In: Wachs IE, editor. Characterization of catalytic materials”, Boston: Manning Publications Co., 6., 1992.

Lawrence, NJ, “Synthesis and Catalytic Activity of Nanostructured Cerium Oxide”, MSc Thesis, University of Nebraska, Lincoln, ABD, 2010.

Ertl, G., Knözinger, H., Weitkamp, J. Preparation of solid catalysts. New York: John Wiley and Sons, 128–130, 1999.

Mali, A., Ataie, A., “Influence of the metal nitrates to citric acid molar ratio on the combustion process and phase constitution of barium hexaferrite particles prepared by sol–gel combustion method”, Ceramics International, 30, 1979-1983, 2004.

Sheerin, E, Gunugunuri, KR, Panagiotis, S,” Evaluation of Rh/CexTi1−xO2 catalysts for synthesis of oxygenates from syngas using XPS and TPR techniques”, Catalysis Today, 263, 75–83, 2016.

Internet:URL:http://www.webcitation.org/query?url=http%3A%2F%2Fsrdata.nist.gov%2Fxps%2FselEnergyType.aspx&date=2016-03-19.

Yasyerli, S, Dogu, G, Ar, I, Dogu, T, “ Actvities of copper oxide and Cu-V and Cu-Mo mixed oxides for H2S removal in the presence and absence of hydrogen and prediction of a deactivation model", Industrıal &Engineering Chemistry Research, 40, 5206-5214, 2001.

Yasyerli, S, Dogu, G, Ar, I, Dogu, T., “ Breakthrough analysis of H2S removal on Cu-V-Mo, Cu-V and Cu-Mo mixed oxides”, Chemical Engineering Communications, 190, 1055-1072, 2003.




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