PRODUCTION OF MOLECULAR HYDROGEN FORMED BY THE THERMAL AND RADIATION-THERMAL TRANSFORMATION OF WATER IN THE NANO-Si+H2O SYSTEM

It were studied the regularities of the dependence of the yield of molecular hydrogen obtained during the thermal and radiation-thermal transformation of water under the action of gamma quanta (Co-60, P = 18.17 rad/s) on the nano-Si+H2O system with particle sizes d(si)= 50 nm on the temperature (T = 300, 373, 473, 573, 623, and 673 K) of the total system and on the water vapor density (rho = 0.25, 0.5, 1, 3, and 8 mg/cm(3)) at a constant temperature of T= 673K. In this system, in a reaction medium with a water vapor density p=8 mg/cm(3) in the temperature range 300 <= T <= 473 K, molecular hydrogen is obtained only by radiation-thermal, and in the temperature range 573 <= T <= 673 K - by thermal and radiation-thermal methods. In the temperature range 300 <= T <= 473 K, the activation energy of the radiation-thermal process is 1.07 kJ/mol, and in the temperature range 573 <= T <= 673 K, the activation energy of the thermal and radiation-thermal processes is 68.6 and 53.83 kJ/mol, respectively. At a temperature of T = 673 K, the yield and the rate of formation of molecular hydrogen obtained in the thermal and radiation-thermal transformation of water vapor in the reaction medium increase in direct proportion to the its density at rho < 3 mg/cm(3), and at rho >= 3 mg/cm(3) a sharp decrease in the angle slope is observed.