Development of Gasoline reforming system for automobile using microwave steam plasma

针对燃料电池汽车供氢系统的研制，研究了常压下微波蒸汽等离子体重整汽油制氢。首先，我们对蒸汽等离子体的点火和稳定性进行了实验，发现氩气适合点燃等离子体，而切向注入蒸汽使等离子体稳定。然后以正己烷和正辛烷为模型进行了汽油重整实验。等离子体的光学发射分析证实了蒸汽和碳氢化合物的解离。产物气体中含有高浓度的一氧化碳和氢气，表明等离子体重整成功。结合实验数据，利用过程模拟器对重整过程进行了评价。结果表明，该系统的能量传递效率太低，需要对系统进行改造，包括等离子炬。综上所述，确定了本方法的以下特征：(1)考虑到等离子体系统的尺寸，系统的小型化是可行的；(2)由于不需要催化剂，重整过程的稳定性和耐久性高，并且易于维护；(3)由于重整反应在等离子体中立即发生，可以实现快速响应和启动；(4)可以使用多种碳质材料。(5)可提供高浓度氢气，实现单位物料制氢效率。

Hydrogen production by gasoline reforming has been studied with microwave steam plasma under atmospheric pressure aiming to the development of hydrogen supply system for fuel cell automobiles. First, we carried out the experiments on the ignition and stability of the steam plasma and found that argon gas was suitable to ignite the plasma, while tangential injection of steam stabilized the plasma. Then the reforming experiments were performed using n-hexane and i-octane as models of gasoline. The optical emission analyses of the plasma confirmed the dissociations of steam and hydrocarbons. The products gases contained carbon monoxide and hydrogen in high concentrations, suggesting that the plasma reforming was succeeded. The evaluation on the reforming process was also carried out using a process simulator with the experimental data. The results indicated that the energy transfer efficiency was too low and modifications of the system including plasma torch were required. In conclusion, the following features of the present method have been confirmed; (1)the miniaturization of the system is feasible considering the size of the plasma system, (2)high stability and durability as well as easy maintenance on the reforming could be attained due to unnecessity of catalysts, (3 fast response and start-up can be achieved because reforming reactions take place immediately in the plasma, (4)various carbonous materials can be used, (5)High concentration of hydrogen can be provided and efficient production of hydrogen per unit of materials can be achieved.