Hiraki Takehito, Yamauchi Satoru, Iida Masayasu, Uesugi Hiroshi, Akiyama Tomohiro
Center for Advanced Research of Energy Conversion Materials, Hokkaido University, Kita 13 Nishi 8, Kita-ku, Sapporo 060-8628, Japan.
Environ Sci Technol. 2007 Jun 15;41(12):4454-7. doi: 10.1021/es062883l.
An innovative environmently friendly hydrolysis process for recycling waste aluminum with the generation of high-pressure hydrogen has been proposed and experimentally validated. The effect of the concentration of sodium hydroxide solution on hydrogen generation rate was the main focus of the study. In the experiments, distilled water and aluminum powder were placed in the pressure-resistance reactor made of Hastelloy, and was compressed to a desired constant water pressure using a liquid pump. The sodium hydroxide solution was supplied by liquid pump with different concentrations (from 1.0 to 5.0 mol/dm3) at a constant flow rate into the reactor by replacing the distilled water, and the rate of hydrogen generated was measured simultaneously. The liquid temperature in the reactor increased due to the exothermic reaction given by Al + OH(-) + 3H2O = 1.5H2 + Al(OH)4(-) + 415.6 kJ. Therefore, a high-pressure hydrogen was generated at room temperature by mixing waste aluminum and sodium hydroxide solution. As the hydrogen compressor used in this process consumes less energy than the conventional one, the generation of hydrogen having a pressure of almost 30 MPa was experimentally validated together with Al(OH)3, a useful byproduct.
提出了一种创新的环境友好型水解工艺，用于回收废铝并产生高压氢气，并通过实验进行了验证。研究的主要重点是氢氧化钠溶液浓度对氢气产生速率的影响。在实验中，将蒸馏水和铝粉置于由哈氏合金制成的耐压反应器中，并用液泵将其压缩至所需的恒定水压。通过液泵以不同浓度（1.0至5.0摩尔/立方分米）、恒定流速将氢氧化钠溶液通过替换蒸馏水的方式供应至反应器中，同时测量氢气产生速率。由于铝与氢氧根离子和3个水分子反应生成1.5个氢气分子、铝酸根离子并释放415.6千焦热量的放热反应，反应器内液体温度升高。因此，通过将废铝与氢氧化钠溶液混合，在室温下产生了高压氢气。由于该工艺中使用的氢气压缩机比传统压缩机消耗的能量更少，实验验证了几乎30兆帕压力氢气的产生以及有用副产品氢氧化铝的生成。
