TREATMENT OF LAKE WATER FROM TAYLOR’S UNIVERSITY USING ADSORPTION COLUMN

Based on lake water report 2010, the presence of high dissolved oxygen and turbidity as well as high amount of copper in lake water showed the importance of treatment needed for TU lake water, thus adsorption process was selected in this study. Rice husk was chosen as the adsorbent due to the effectiveness in removing heavy metals and dyes as well as the abundant amount in Malaysia. Rice husk was modified or pre-treated with H3PO4 to increase the adsorptive capacity and two types of study were conducted; batch and column studies. Batch study was performed to analyse the effect of COD and turbidity when undergo adsorption process. Column study used acrylic column with 7 cm adsorbent bed height to investigate the removal of copper ion with different flow rate. Rice husk surface area increased from 1.0459 m^2/g to 1.6455 m^2/g after treatment. At optimum contact time, the highest COD and turbidity percentage removal was 25.43% and 80.77% respectively. 1.0g adsorbent dosage is the optimum amount of adsorbent to remove 26.59% COD and 80.77% turbidity exist in lake water. Lowest flow rate at 5 ml/min removed 81.5% of copper ion from lake water. The adsorption of TU lake water onto the H3PO4 treated rice husk favoured Langmuir isotherm and fitted well with pseudo-second-order model which indicates chemisorption process. In column study, the adsorption implied Yoon and Nelson model with the highest value of correlation coefficients.