TEMPERATURE-DEPENDENCE OF TRIHALOMETHANE ADSORPTION ON ACTIVATED CARBON - IMPLICATIONS FOR SYSTEMS WITH SEASONAL-VARIATIONS IN TEMPERATURE AND CONCENTRATION

Adsorption isotherms have been measured for chloroform, bromodichloromethane, dibromochloromethane, and bromoform on granular activated carbon (GAC, Calgon F400) at 4, 15, 30, and 45 degree C. Coefficients of Langmuir and Freundlich isotherms are given and compared to isotherms reported in the literature for trihalomethanes. Long-term seasonal variations in temperatures and chloroform concentration, which occur in surface water treatment, were shown to correspond to a relatively minimal change (26%) in GAC capacity; much larger long-term seasonal variations in GAC capacity would be expected for volatile organics with similar adsorption isotherms, if their seasonal variations in concentration are not determined by the kinetics of chlorination and its temperature dependence.