Abstract: Surface coatings developed in different water obtained by means of stepwise filtration were used to assay the effect of suspended particulates on trace metal adsorption to them. There was a statistically significant correlation relationship between the contents of iron and manganese oxides on surface coatings and those in water, in which surface coatings were developed, even though manganese oxides was influenced obviously by particulates suspended in waters. The classical Langmuir adsorption isotherm was suitable to describe Pb and Cd adsorption to the surface coatings. It was observed that all of the iron oxides on the surface coatings contributed to Pb adsorption while manganese oxides on surface coatings developed in waters containing suspended particulates with a greater diameter contributed most to Cd adsorption. However, the adsorption capacities of Pb and Cd to the surface coatings increased with the decrease of diameter of suspended particulates in water.

Key words: Surface coatings, Suspended particulate, Cd, Pb, Adsorption