Removal of Pb(II) and As(V) From Water: A Comparison Study Using Different Adsorbents

摘要

This study evaluated the effectiveness of various adsorbents for arsenate (As(V)) and lead ((Pb(II)) removal in drinking water. Metal oxides modified-activated carbons (MAC), metal oxides modified-activated alumina (MAA), and other commercial materials were selected to be the adsorbents. Batch experiments were conducted to investigate the performance of As(V) and Pb(II) removal by these adsorbents. The results demonstrated that MAC had a better Pb(II) adsorption rate than AA and TiO2 in a wide range of pH 4-9. Besides, MAA exhibited a better As(V) adsorption rate than AA and TiO2 from pH 4 to 9. Advantages of the MAC and MAA were further demonstrated by column filtrations using Pb(II)-spiked and As(V)-spiked aged tap water, respectively. Approximately 34,000 bed volumes (BVs) of Pb(II)-spiked tap water with 200 mug/L Pb(II) were filtered by MAC column before the effluent Pb(II) concentration exceeded 15 mug/L. Instead, only 2,880 BVs of Pb(II)-spiked water were filtered by AC column. Modification with metal oxides also improved As(V) removal efficiency of AA. The breakthrough of MAA bed occurred 700 BVs later than AA when spiked tap water with 100 mug/L As(V) were filtered. The results from this study revealed the high effectiveness of MAC and MAA for Pb(II) and As(V) removal, respectively.