CORRELATION OF FREUNDLICH Kd AND n RETENTION PARAMETERS WITH SOILS AND ELEMENTS

Publisher Website
Google Scholar
Abstract
We studied the retention of 15 elements by 11 soils from 10 soil orders to determine the effects of element and soil properties on the magnitude of the Freundlich parameters Kd and n. The magnitude of Kd and n was related to both soil and element properties. Strongly retained elements, such as Cu, Hg, Pb, V, and P had the highest Kd values. The transition metal cations Co and Ni had similar Kd and n values, as did the group IIB elements Zn and Cd. Oxyanion species tended to have lower n values than did cation species. Soil pH and CEC were significantly correlated with log Kd values for cation species. High pH and high CEC soils retained greater quantities of the cation species than did low pH and low CEC soils. A significant negative correlation between soil pH and the Freundlich parameter n was observed for cation species, whereas a significant positive correlation between soil pH and n for Cr(VI) was found. Greater quantities of anion species were retained by soils with high amounts of amorphous iron oxides, aluminum oxides, and amorphous material than were retained by soils with low amounts of these minerals. Several anion species were not retained by high pH soils. Despite the facts that element retention by soils is the result of many interacting processes and that many factors influence retention, significant relationships among retention parameters and soil and element properties exist even among soils with greatly different characteristics. © Williams & Wilkins 1989. All Rights Reserved.