SODYUM BOR HİDRÜRÜN HİDROLİZİNDE KARBON NANOTÜP DESTEKLİ Co-Cr-B KATALİZÖRÜN KULLANILMASI

Year 2021, Volume: 9 , 29 - 41, 30.12.2021

Orhan Baytar , Selman Ağrak Halil Demir , Ömer Şahin

https://doi.org/10.36306/konjes.979035

Abstract

Artan teknoloji ile birlikte hem enerji ihtiyacı artmakta hem de mevcut fosil yakıtların miktarı gün geçtikçe azalmaktadır. Fosil yakıtların azalması ve enerji ihtiyacının artması araştırmacıları yenilenebilir enerji kaynakları için araştırmaya yönlendirmiştir. Hidrojen enerjisi bu yenilenebilir enerji kaynaklardan bir tanesidir. Sodyum borhidrür(NaBH4) hidrojen taşıyıcısıdır. Sodyum borhidrür hidrolizinde açığa çıkan hidrojenin yarısının sudan gelmesi büyük bir avantajdır. Bu çalışmada, NaBH4 hidrolizinde kullanılmak üzere karbon nanotüp destekli(KNT) Co-Cr-B katalizörü sentezlenmiştir. Sentezlenen katalizörün karakterizasyonu SEM, EDX, XRD ve BET ile gerçekleştirilmiştir. NaBH4 hidrolizinde NaOH konsantrasyonu, NaBH4 konsantrasyonu, katalizör miktarı ve sıcaklık parametrelerin etkisi incelenmiştir. Desteksiz Co-Cr-B katalizörün hidrojen üretim hızı 3560 ml.g-1.dk-1. iken KNT destekli Co-Cr-B katalizörün hidrojen üretim hızı 6600 ml.g-1.dk-1. olarak belirlenmiştir. NaBH4 hidroliz aktivasyon enerjisi ve kinetiği tespit edilmiş ve sırasıyla 55,88 kj/mol ve 0,2 olduğu tespit edilmiştir.

Keywords

Sodyum borhidrür, hidroliz, KNT, Co-Cr-B katalizör

Supporting Institution

Siirt Üniversitesi BAP Koordinatörlüğü

Project Number

2017-SİÜFEB-27

Use of Carbon Nanotube Supported Co-Cr-B Catalyst in the Hydrolysis of Sodium Borohydride

Abstract

With the increasing technology, the need for energy increases and the amount of fossil fuels available decreases over time. The decrease in fossil fuels and the increase in energy needs have prompted researchers to find new sources for renewable energy sources. Hydrogen energy is one of these renewable energy sources. Sodium borohydride (NaBH4) is a good source and carrier of hydrogen. Half of the hydrogen released in the hydrolysis of NaBH4 comes from water, which is a great advantage. In this study, carbon nanotube(CNT) supported Co-Cr-B catalyst was synthesized to be used in NaBH4 hydrolysis. The characterization of the synthesized catalyst was carried out with SEM, EDX, XRD and BET. The effects of parameters such as NaOH concentration, NaBH4 concentration, amount of catalyst and temperature on NaBH4 hydrolysis were investigated. While the hydrogen production rate of the unsupported Co-Cr-B catalyst was 3560 ml.g-1.dk-1, the hydrogen production rate of the CNT supported Co-Cr-B catalyst was determined as 6600 ml.g-1.dk-1. The kinetic order of hyrolysis and activation energy of NaBH4 were found as 0.2 and 55.88 kJ/mol, respectively.

Keywords

Sodium borohydride, hydrolysis, CNT, Co-Cr-B catalyst

Project Number

2017-SİÜFEB-27

References

• Bai, Y., Wu, C., Wu, F., Yi, B., 2006, “Carbon-supported platinum catalysts for on-site hydrogen generation from NaBH4 solution”, Materials Letters, Vol. 60(17-18), pp. 2236-2239.
• Baytar, O., İzgi, M.S., Horoz, S., Şahin, Ö., Nar, S., 2019, “Al2O3 supported Co-Cu-B (Co-Cu-B/Al2O3) catalyst for hydrogen generation by hydrolysis of aqueous sodium borohydride (NaBH4) solutions”, Dig J Nanomater Biostruct, Vol.14(3), pp. 673-681.
• Baytar, O., 2018, “Investigation of high-activity activated carbon-supported Co-Cr-B catalyst in the generation of hydrogen from hydrolysis of sodium borohydride”, Acta Chimica Slovenica, Vol. 65(2), pp. 407-415.
• Baydaroglu, F., Özdemir, E., Hasimoglu, A., 2014, “An effective synthesis route for improving the catalytic activity of carbon-supported Co–B catalyst for hydrogen generation through hydrolysis of NaBH4”, International Journal of Hydrogen Energy, Vol.39(3), pp:1516-1522.
• Demirci, U.B., Miele, P., 2014, “Cobalt-based catalysts for the hydrolysis of NaBH4 and NH3BH3”, Physical Chemistry Chemical Physics, Vol.16(15), pp. 6872-6885.
• Deonikar, V.G., Rathod, P. V., Pornea, A.M., Puguan, J.M.C., Park, K., Kima, H., 2020, “Hydrogen generation from catalytic hydrolysis of sodium borohydride by a Cu and Mo promoted Co catalyst”, Journal of Industrial and Engineering Chemistry, Vol.86, pp. 167-177.
• Eckenhoff, W.T., 2018, “Molecular catalysts of Co, Ni, Fe, and Mo for hydrogen generation in artificial photosynthetic systems”, Coordination Chemistry Reviews, Vol. 373, pp. 295-316.
• Ekinci, A., Cengiz, E., Kuncan, M., Şahin, Ö., 2020, “Hydrolysis of sodium borohydride solutions both in the presence of Ni–B catalyst and in the case of microwave application”, International Journal of Hydrogen Energy, Vol. 45(60), pp. 34749-34760.
• Ekıncı, A., 2020, “Hydrogen Generation by Hydrolysis of NaBH 4 with Efficient Co–La–Mo–B Catalyst for PEM Fuel Cells”, Kinetics and Catalysis, Vol.61(4), pp. 589-594.
• Fernandes, R., Patel, N., Miotello, A., 2009,”Hydrogen generation by hydrolysis of alkaline NaBH4 solution with Cr-promoted Co–B amorphous catalyst”, Applied Catalysis B: Environmental, Vol.92, pp.68–74.
• Guella, G. C., Patton, Z.B., Miotello, A., 2006, “New insights on the mechanism of palladium-catalyzed hydrolysis of sodium borohydride from 11B NMR measurements”, The Journal of Physical Chemistry B, Vol.110(34), pp. 17024-17033.
• Hemmati, J.C., Ocelík R.V., De Hosson, J.Th.M., 2013, “Electron microscopy characterization of Ni-Cr-B-Si-C laser deposited coatings”, Microsc Microanal., Vol. 19(1), pp. 120-131.
• Huang, Y.H., Su, C.C., Wang, S.L., Lu, M.C., 2012, “Development of Al2O3 carrier-Ru composite catalyst for hydrogen generation from alkaline NaBH4 hydrolysis”, Energy, Vol.46(1), pp. 242-247.
• Huang, Y., Wang, y., Zhao, R., Shen, P.K., Wei, Z., 2008, “Accurately measuring the hydrogen generation rate for hydrolysis of sodium borohydride on multiwalled carbon nanotubes/Co–B catalysts”, international journal of hydrogen energy, Vol.33, pp.7110–7115.
• İzgi, M.S., Baytar, O., Şahin, Ö., Kazıcı H.Ç., 2020,”CeO2 supported multimetallic nano materials as an efficient catalyst for hydrogen generation from the hydrolysis of NaBH4”, International Journal of Hydrogen Energy, Vol.45(60), pp. 34857-34866.
• İzgi, M.S., Baytar, O., Şahin, Ö., Horoz S., 2019, “Studies on catalytic behavior of Co–Cr–B/Al2O3 in hydrogen generation by hydrolysis of NaBH4”, Digest Journal of Nanomaterials and Biostructures, Vol.14(4), pp.1005-1012.
• Lee, J., Shin, H., Choi, S. K., Lee, J., Choi, J.Y., Yu, H.K., 2019, “Carbon layer supported nickel catalyst for sodium borohydride (NaBH4) dehydrogenation”, International Journal of Hydrogen Energy, Vol.44(5), pp. 2943-2950.
• Larichev, Y.V., Netskina, O.V., Komova, O.V., Simagina, V.I., 2010,”Comparative XPS study of Rh/Al2O3 and Rh/TiO2 as catalysts for NaBH4 hydrolysis”, International Journal of Hydrogen Energy, Vol.35(13), pp. 6501-6507.
• Modisha, M.P., Ouma, N.M.C., Garidzirai, R., Wasserscheid, P., Bessarabov, D., 2019,"The prospect of hydrogen storage using liquid organic hydrogen carriers", Energy & fuels, Vol. 33(4), pp. 2778-2796.