Abstract:

Hydrogen production by hydrolysis of sodium borohydride by means of metal catalyst is a practical，environment-friendly and feasible approach. Especially，using the solid state sodium borohydride or its mixture directly is simpler and safer than using its solution. The present work was focused on the design of a small scale generator suitable for H₂ generation from the mixture powders of sodium borohydride and cobalt acetate as catalyst precursor at a reasonable temperature and at high generation efficiency. The initial temperature，flow rate of water，mixture ratio and product composition were investigated experimentally. It was found that the process temperature measured directly by a thermocouple fluctuated in a small range of 6～8 ℃，which could decrease the peak value of H₂ generation rate and obtain a steady hydrogen flow. A high H₂ generation efficiency > 95% was achieved under the mixture ratio with the catalyst being more than 4%. The catalyst cobalt acetate was formed in-situ and evenly distributed.

摘要：

硼氢化钠催化水解制氢是一项实用、环保、可行的制氢技术。直接应用固态的硼氢化钠或与催化剂的混合物制氢比使用其溶液制氢更便捷、安全。本文设计了小型制氢反应器，使用NaBH₄和乙酸钴粉末的混合物作初始反应物。研究了初始反应温度、供水速率和NaBH₄与乙酸钴的混合比对产氢特性的影响。实验结果表明，反应区外围使用冷却水时，可将反应温度波动控制在6～8 ℃，这有利于降低氢气流速的峰值和保持相对稳定的氢气流。当催化剂的混合量大于4%时，氢气的转化率可达95%以上。