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Metal hydrides are the leading boron based compounds used in hydrogen storage. Potassium boron is hydride; low cost, non-toxic, stable at high temperatures of these compounds, etc. as it is an important source of hydrogen storage due to its properties. Potassium boron hydride, which provides hydrogen as much as the hydrogen supplied from water as a result of hydrolysis, provides many advantages if it is used as a hydrogen source. In this study, the catalytic parameters of bimetallic nanocatalyst synthesized from cobalt (Co) and chromium (Cr) were investigated so as to use in potassium boron hydride hydrolysis. For the catalyst synthesis and effect, the optimum data for the hydrolysis reaction were obtained in the light of metal incorporation ratio, solvent medium, catalyst amount, potassium borohydride concentration and temperature parameters, respectively. Under the best conditions, the hydrogen production rate was determined as 2448.24 mL/g.min. As a result of repeated use to determine the catalyst performance, it was determined that 100% product yield was achieved until the 8th use. When the reaction kinetics were examined, it was determined that the reaction was of the 0 th order and the activation energy of the reaction was 41.3 kJ/mol. As a result of the study, it is considered that the use of Co-Cr catalyst for hydrogen production will be appropriate if potassium boron hydride is used as a hydrogen source in fuel cells. Since potassium borohydride stores less hydrogen than other hydrogen-storing compounds, it has not been studied much until now. However, as shown in this study, it enables pretty high hydrogen production. Therefore, it is expected to encounter many similar studies in the future., Hidrojen depolamada kullanılan bor kaynaklı bileşiklerin başında metal hidrürler gelmektedir. Bu bileşiklerden potasyum borhidrür; düşük maliyetli olması, zehirli olmaması, yüksek sıcaklıklarda kararlı olması vb. özelliklerinden dolayı önemli bir hidrojen depolama kaynağıdır. Hidroliz sonucunda kendi yapısındaki hidrojen kadar hidrojenin sudan temin edilmesini sağlayan potasyum borhidrür, hidrojen kaynağı olarak kullanılması durumunda birçok avantaj sağlamaktadır. Bu çalışmada, potasyum borhidrür hidrolizinde kullanılmak üzere kobalt (Co) ve kromdan (Cr) sentezlenen bimetalik nanokatalizörün katalitik parametreleri incelenmiştir. Katalizör sentezi ve etkisi için sırasıyla metal birleşme oranı, çözücü ortamı, katalizör miktarı, potasyum borhidrür konsantrasyonu ve sıcaklık parametreleri ışığında hidroliz tepkimesi optimum verileri elde edilmiştir. En iyi şartlarda hidrojen üretim hızı 2448,24 mL/g.min olarak belirlenmiştir. Katalizör performansını belirlemek üzere yapılan tekrarlı kullanımlar sonucunda 8. Kullanıma kadar %100 ürün veriminin sağlandığı belirlenmiştir. Tepkime kinetiği incelendiğinde tepkimenin 0. Dereceden olduğu, tepkime aktivasyon enerjisinin ise 41,3 kJ/mol olduğu belirlenmiştir. Çalışma sonucu olarak yakıt hücrelerinde hidrojen kaynağı olarak potasyum borhidrürün kullanılması durumunda hidrojen üretimi için Co-Cr katalizörünün kullanımının yerinde olacağı değerlendirilmektedir. Potasyum borhidrür, diğer hidrojen depolama özelliğindeki bileşiklere göre daha az oranda hidrojen depoladığından bugüne kadar çok araştırılmamıştır. Fakat bu çalışmada görüldüğü gibi hidrolizi sonucunda yüksek oranda hidrojen üretimi sağlanmıştır. Dolayısıyla, ileriki süreçte benzer çalışmalarla çokça karşılaşılması beklenmektedir.

In this study, Al2O3 supported Co-Cu-B (Co-Cu-B/Al2O3) catalyst was synthesized by chemical impregnation and precipitation method to be used for catalytic hydrogen generation from NaBH4. Co-Cu-B/Al2O3 catalyst was synthesized at various ratios using Co-Cu-B/Al2O3 (5-20%). The effect of some parameters such as NaOH concentration (0- 7%), NaBH4 concentration (2.5-7.5%), catalyst amount (25-150 mg) and solution ambient temperature was investigated on the catalytic hydrolysis of NaBH4. The hydrogen generation rate was found as 2519 and 8962 mL*g-1 *min-1 for Co-Cu-B and Co-CuB/Al2O3 catalysts in NaBH4 hydrolysis, respectively. The order rate kinetics and activation energy for Co-Cu-B/Al2O3 catalyst were determined as 0.125 and 27 kJ*mol-1 , respectively. The obtained results suggest that Co-Cu-B/Al2O3 catalysts can be used for mobile applications of PEMFC systems.

This assay investigates the Co-Cr-B catalyst effect supported on γ-Al2O3 to produce hydrogen (HG) from ammonia-borane hydrolysis (ABH). For characterization of this catalyst, SEM-EDX, XRD, FTIR and BET surface area analysis were performed. The maximum hydrogen generation rate (HGR) with this catalyst used for the ABH was 3260 ml min−1 g−1catalyst. The recyclability tests for the Co-Cr-B/γ-AlO3 catalyst on the ABH have maintained an activity of 68% even after four hydrolysis treatments. Also, the activation energy (Ea) obtained using the Co-Cr-B catalyst supported on γ-AlO3 for the ABH was 56.06 kJ/mol.

In this present study, the chemical reduction technique was used to synthesize Al2O3 supported Co-Cr-B catalyst (Co-Cr-B/Al2O3). The effects of the concentration of NaBH4, NaOH, amount of catalyst, ratio of metal/ Al2O3and temperature were discussed in detail. The results show that the reaction rate of hydrolysis first rises up and then goes down subsequently with the increase of NaBH4 concentration, as well as the concentration of NaOH. It was observed that the hydrogen generation rate increases with the molar content of metal changing from 2.5% to 5 wt%. However, when the metal/Al2O3 molar ratio is located from 5% to 20 wt%, the rate of hydrogen generation goes down. The hydrolysis kinetic order and the activation energy ....