ABSTRACT
This work had the objectives of the evaluation of parameters of the models of isotherms of Freundlich and Langmüir that best reflect the adsorption of Pb, Cu and Zn in weathered soils and to identify the relationship between the selected parameters and the chemical and physical attributes of the twelve more representative classes of soils in Brazil. Were the collection places including “ pedons “ of the areas South, Southeas and North of the country. It was evaluated, through the trail analysis, the unfolding of the correlation coefficient among variables dependent obtained through the isotherms of adsorption (parameters of adsorption) and variables independent (chemical and physical attributes), in coming direct and indirect effects for the elements Pb, Cu and Zn. The attributes of the soil: clay; organic carbon; effective cation exchange capacity; iron citrate dithionitebicarbonate; total aluminum, in were presented in larger coefficients of simple correlation with the parameters of adsorption and they were used in the model of the trail analysis to explain adsorption of heavy metals. The main conclusions of this work were: the trail analysis was shown as an important tool in the study of the behavior of the heavy metals in the soil; constant KF for all the elements presented the higher determination coefficient and the small value of the effect of the residual variable and, the variables that more contributed with the adsorption of heavy metals were Corg., CTCE, pH, ARG and Al2O3.
Key words:
heavy metal; isotherms of Freundlich and Langmüir