Synergistic effect on hydrolytic sodium borohydride adding waste Al for hydrogen generation

• Published in: International journal of hydrogen energy 2020-03, Vol.45 (17), p.10334-10341
• Main Authors: Hsieh, Cheng Pu, Ho, Ching Yuan, Hsu, Li Chung, Chang, Yaw-Jen
• Format: Article
• Language: English
• Subjects: Acid catalyst; Hydrogen generation; Mutual effect; Sodium borohydride; Waste aluminum can
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2019.03.194

Synergistic effect of sodium borohydride (NaBH4) mixed with waste aluminum in hydrolytic system were investigated to improve the hydrogen generation (HG) efficiency. The alkaline aqueous originated from NaBH4 hydrolysis impels the passive aluminum hydroxide film of Al surface to be dissolved, thus, mutual effect of HG amount increasing by 88% and 50% for Al powder and waste Al can, respectively. To add acid catalyst in the mutual mixture system prompts to significantly accelerate HG rate from 100 ml/min˙g to 400 ml/min˙g but raising temperature is not obviously found. It is speculated that exothermic effect dominates the NaBH4 hydrolytic reaction and eliminates the temperature effect. In this study, the mutual hydrolyzed reaction of NaBH4 and waste Al provides ecofriendly environment, low cost and enables to achieve higher HG rate and further uses for portable/mobile fields. [Display omitted] •High hydrogen generation of NaBH4 mixed with waste Al is achieved.•NaBH4 is hydrolyze to create alkaline solution and dissolve oxide on Al surface.•Synergistic hydrogen generation is obvious without extra adding alkaline solvent.•Adding catalyst in the mutual mixture system prompts to accelerate hydrogen gas.•Temperature effect is insignificant due to exothermic reaction in this mixture.