Experimental study on the adsorption and desorption behaviours of methane in clay minerals

There is a good positive correlation between the specific surface area and the Langmuir volume VL of methane, R2 reached 0.9219. The desorption process of methane shows obvious desorption hysteresis, under the same pressure, the methane adsorption amount in the desorption process is always more than that in the adsorption process, and the difference between the two is the largest when the pressure is about 5 MPa. As the pressure decreases, the desorption efficiency all show an increasing trend. When the pressure is high, the desorption efficiency curve rises slowly and the desorption efficiency is low. When the pressure is lower than about 5 MPa, the methane desorption efficiency enters a rapid increase stage, and the amount of methane desorption increases rapidly. The methane desorption hysteresis coefficients of clay minerals are different, in which the maximum of Montmorillonite is 41.91% and the minimum of Illite is 18.57%. [Received: February 13, 2023; Accepted: February 13, 2024]