... and adsorption water,ammonia gas, hydrogen sulfide, carbon dioxide. 4A molecular sieve is used for gas, liquid of dryness and ... sulfide, carbon dioxide, sulphur dioxide, ethanol, ethane,ethylene, propylene etc.4A molecular sieve cann’t adsorb propane and the molecular which ... are bigger than propane molecular.4A molecular sieve is also used for dryness of impurity ...