Study on Gas Adsorption Capacity on Coal Surface Under High Temperature and Pressure

The adsorption laws of gas on the surface of three kinds of coal samples under high temperature and pressure were studied experimentally. Research shows that the gas adsorption under high temperature and pressure could be described by Langmuir model. At the same pressure condition, the gas adsorption capacity decreases with the increase of temperature. The gas saturated adsorption capacity decreases with the increase of temperature, the Langmuir adsorption pressure of the coal samples with high degree of metamorphism decreases faster with the increase of temperature than that of the other two coal samples. In addition, the saturated adsorption amount of gas at different temperature increases with the increase of fixed carbon content. At 25, 40, 80 ℃, the saturated adsorption decreases with the increase of volatile matter content, but at 120 ℃, it first decreases and then increases.