Abstract
Humic acid is one of the main components of organic matters in the water environment. In this study, some effects of temperature on the copper adsorption to the humic acid extracted from cray soil (PFAHA) was examined. Complex formation constant (KCu2+) of the phenolic sites in the humic acid decreased as the temperature increased. In contrast, KCuOH+ increased as the temperature increased. That the ratio of CuOH+ to Cu2+ in the solution increased as the temperature increased. Adsorption enthalpy of phenolic sites were larger than those of carboxylic sites because it is estimated that change of adsorption species (CuOH+) appeared at the higher pH. A linear relationship was found between the complex formation constants and the temperature according to the van't Hoff equation.
