In this study, the sorption of Cu and Zn onto NaOH-treated oil palm frond (OPF) in a fixed-bed up flow column operated in continuous mode at hydraulic retention times (HRTs) of 6, 12 and 18 min was investigated. The column was operated at room temperature and fed with 100 mg/l of heavy metal solution. The data confirmed high ability of sorption in continuous mode (>90% removal) and breakthrough occurred after 216 min. The whole continuous sorption process was simulated using an empirical model and the parameters were estimated. The fitting of experimental data to different models such as Adams-Bohart. Wolborska, Thomas and Yoon and Nelson Models was also tested for comparison. The best fitting was generally obtained with Adams-Bohart model which showed high degree of fitting within this HRT range. The software used the experimental data to fit a model to simulate the behaviour of the continuous System and was based oil the concentration of the effluent and time as the main variables. A high accuracy (R-2 > 0.96) was achieved and the model was modified to be used for the heavy metal sorption system. (C) 2008 Published by Elsevier B.V.