Effects of mixed ethanol on adsorption of gaseous toluene by granular activated carbon

摘要

Mobile internal circulation cabinets, equipped with granular activated carbon (GAC) to adsorb volatile organic compounds (VOCs), are extensively applied to store organic solvents in Taiwanese university and college laboratories. This work evaluates how mixed ethanol affects the toluene adsorption capacity on GAC for serious chemical emission in internal circulation cabinets. Experimental results demonstrate that the toluene adsorption capacity [Q, g toluene (g GAC) ~(-1)] is linearly simulated as the natural logarithm of adsorption time for 464-2652 ppm toluene at 27 deg C. In advance, the equilibrium adsorption capacity [Q_e, g toluene (g GAC) ~(-1)] is simulated as the inlet toluene concentration based on the Langmuir formula. A low concentration ratio of mixed VOCs (ethanol/toluene < 0.2) rarely influence the VOC adsorption capacity; but when the concentration ratio of ethanol/toluene > 0.45, competitive adsorption between hydrophilic and hydrophobic VOCs, reducing the adsorption capacity of the single VOC component, is dominant.