EFFECT OF MOLECULAR-OXYGEN ON ADSORPTIVE CAPACITY AND EXTRACTION EFFICIENCY OF GRANULATED ACTIVATED CARBON FOR 3 ORTHO-SUBSTITUTED PHENOLS

Adsorptive capacity of activated carbon for several organic compounds was found to be strongly influenced by the presence of molecular oxyge n. This influence is manifested by the polymerization of adsorbate on the surface of activated carbon. As a result, GAC exhibits much higher adsorptive capacities for these compounds under oxic rather than unde r anoxic conditions. Therefore, a new experimental procedure for condu cting adsorption isotherm tests is investigated in this work. The resu lts of kinetic experiments show that this polymerization of adsorbate proceeds at a very slow rate which extends the time required for equil ibrium conditions to be established. Extraction efficiency obtained fo r GAC used in anoxic isotherm experiments were significantly higher th an those obtained for GAC used in isotherm experiments conducted in th e presence of molecular oxygen.