Gas adsorption unit is used to separate a gas component from a gas mixture so that the gas is adsorbed by adsorbent and remaining leaves the column. The desired product can be the adsorbate or the objective of the process can be clean up of the gas mixture from the adsorbed component. Once the adsorption is completed, the adsorbate is removed from the column during desorption and adsorbent can be used again. This process is used in sour natural gas sweetening in which sulfur-containing gas is separated from methane-rich natural gas. This unit comprising a column packed with activated carbon adsorbs a component of a two-component gas mixture, an adsorptive gas and an inert gas, and separate from each other. Heat of adsorption increases the local temperature of the column that is the indication of adsorption and temperature sensors indicate the temperature change. After saturation of a section of the bed, the adsorption occurs in the next section until the column becomes totally saturated. At this point, regeneration of the bed performed using the inert gas.