Commercial alumina balls were employed as support material, and metal cobalt was deposited on their surface via electroless plating, resulting in a series of Co/Al2O3 catalysts with different Co loadings. The prepared catalysts were used for hydrogen production from the catalytic hydrolysis of alkaline sodium borohydride solution. In the present work, effects of Co loading, NaBH4 concentration, reaction temperature and recycling times on the catalyst activity were investigated. The surface morphology, element composition and phase structure of catalysts were analyzed by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD), respectively. The results show that the optimal Co loading is 0.46% (mass fraction); meanwhile, the 5%NaBH4+5%NaOH solution presents the highest hydrogen generation rate up to 3.26 L/(min·g). The apparent activation energy is 64.4 kJ/mol. Compared with the initial performance, the catalyst activity decreases to 72% after recycling for four times.%以商品化的氧化铝球为载体,通过化学镀法在其表面沉积金属钴,制备不同担载量的Co/Al2O3催化剂,并用于催化碱性溶液中硼氢化钠水解放氢反应.考察钴担载量、硼氢化钠浓度、反应温度、循环使用次数对催化剂性能的影响.通过扫描电子显微镜、能谱仪、X射线衍射分别对催化剂表面形貌、元素组成和晶相结构进行分析.结果表明:当钴的担载量为0.46%(质量分数)时,20℃下5NaBH4+5%NaOH体系的产氢速率最高,达3.26 L/(min·g);反应表观活化能为64.4 kJ/mol;循环使用4次后,催化剂活性降至初始值的72%.
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