Development of shock-tube technique for hydrogen production using the low level energy of water vapor

利用激波管产生含碳粒子的高温水蒸气。用水气反应生成碳+水蒸气混合物中的氢和一氧化碳，用同样的方法生成经氩气稀释的高温正辛烷。通过热分解和热氧化以及气体温度的影响生成氢气、乙烯和煤烟，并通过实验观察初始混合比。得到以下结果：(1)激波管试验段用氩气吹胀碳颗粒，氩气吹向碳颗粒，混合气体在反射激波中加热。分别计算了0.63、0.80、1.12、1.52、2.30、3.44、3.92、4.26 μm波长下的单色发射功率时程，并利用hotel - broughton方程计算了粒子温度。结果表明，在1500 ~ 2000k的温度下，可将直径大于5 μm的颗粒加热至200 μs以内的平衡温度。(2)在我们的激波管系统的反射激波中获得了数千ppm的氢气。(3)在激波加热气体中观察到氢气、乙烯和烟尘。预测了甲烷和乙炔的产量。以氦和氮为驱动气体，在T_5=1500 K时，氮气驱动的产氢速率x={H_2}/[C_8H_<18>]约为1，氦驱动的产氢速率约为1/10。本实验以反射激波温度T_5为代表温度，用Arrhenius表达式得到的产氢表观活化能为70 ~ 80 kJ/mol。在2000K下，产氢速率与正辛烷浓度成正比。此外，如果在正辛烷混合物中加入少量的氧气，则产氢速率会变大。从这些结果中我们证实了利用激波系统可以加热低能量气体，并且有可能利用能量从高碳氢化合物中产生氢气用于工业生产。少

The high temperature water-vapor containing carbon-particles was generated by using shock tube. The generation of hydrogen and carbon-monoxide from the carbon + water-vapor mixture were generated from water-gas reaction, And also the high temperature n-octane diluted with argon was generated by the same method. The hydrogen, ethylene, and soot were generated by the thermal decomposition and the thermal oxidation and the influence of the gas temperature, and the initial mixture ratio was observed experimentally. The following results were obtained: (1) the carbon particles blew up with argon in the test section of shock tube, when the argon gas blew on the carbon particles and the mixture was heated in the reflected shock wave. The time histories of the monochromatic emissive powers at the wavelengths 0.63, 0.80, 1.12, 1.52, 2.30, 3.44, 3.92, 4.26 μm were followed and the particle temperature was calculated using the Hottel-Broughton equation. It was confirmed that the particle of 5 μm … More diameter could be heated till the equilibrium temperature within 200 μs at temperature 1500-2000K. (2) The hydrogen gas of several thousands ppm was obtained in the reflected shock wave of our shock tube system. (3) The hydrogen, ethylene and the soot were observed in the shock-heated gas. Production of methane and acetylene was predicted. Helium and nitrogen were used as the driver gas and the rate of hydrogen production x={H_2}/[C_8H_<18>] was about 1 for nitrogen driver and the 1/10 for helium driver at T_5=1500 K. The apparent activation energy for the hydrogen production was 70-80 kJ/mol with the Arrhenius expression, when one used the reflected shock temperature T_5 as the representative temperature in this experiment. The rate of hydrogen production was proportional to the concentration of n-octane under 2000K. Furthermore the hydrogen production rate became larger, if the small amount of oxygen was added in the n-octane mixture.From these results we confirmed that one can heat up the gas of the low-level-energy by using the shock wave system and that there is a possibility that using the energy the hydrogen gas from higher hydrocarbons was produced industrially. Less