Akademik Veri Yönetim Sistemi
Catalysis Letters, cilt.154, sa.9, ss.5006-5021, 2024 (SCI-Expanded)
In this study, a natural zeolite supported Co-B catalyst (Co-B/Zeolite) with a Co content of 10 wt.% was prepared by impregnation and chemical reduction method to release hydrogen gas from an alkaline sodium borohydride (NaBH4) solution. The synthesized catalyst was characterized with various characterization techniques, including X-ray diffraction (XRD), X-ray fluorescence (XRF), inductively coupled plasma mass spectroscopy (ICP-MS), Brunauer–Emmett–Teller (BET), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared (FTIR), and X-ray photoelectron spectroscopy (XPS), etc. It was found that the BET specific surface area of Co-B/Zeolite (26.03 m2 g−1) was roughly double that of the zeolite (13.12 m2 g−1). The Co ratio in the catalyst was found to be 12.02 wt.% by EDX analysis. ICP-MS examination of the catalyst revealed a B/Co atomic ratio of 0.64. No peaks associated with Co-B were observed in the XRD pattern of the catalyst, indicating the amorphous nature of the component. Parameters that have significant effects on the hydrolysis reaction, such as catalyst amount, sodium hydroxide and sodium borohydride concentrations, and reaction temperature, were investigated. The hydrogen generation rate (HGR) was found to be 1732 mL min−1 gcat−1 in the presence of 100 mg of Co-B/Zeolite in 5 wt.% NaOH and 5 wt.% NaBH4 solution at 50 °C. The experimental results were well fitted to the zero-order kinetic model (k0 = 0.0296–0.1619 mol min−1 gcat−1 for 20–50 °C). The activation energy (Ea) of the catalytic reaction was found to be 44.98 kJ mol−1. Meanwhile, the reusability evaluations showed that the catalyst preserves high stability and can still sustain 73% of its initial activity after 5 catalytic cycles. Graphical Abstract: (Figure presented.)