EN
The adsorption behaviors of copper (Cu), zinc (Zn), and nickel (Ni) on red and yellow loesses in Khon Kaen were evaluated by applying small-scale column studies. Continuous flows with the constant flow rate of the influents were consecutively implemented within three different cycles: adsorption, desorption, and adsorption processes. The results illustrated that the adsorption capabilities between cycles I and III were found to be significantly different. The adsorption process in cycle I appeared to be more effective than cycle III due to the availability of more adsorption site and the incomplete desorption of the metal ions from the adsorbent surface. The experimental and theoretical analyses showed that adsorption capacities were in the order of Cu