Removal of Chromium (VI) and Lead (II) by using sawdust activated carbon as compared with commercial activated carbon / Norlina Hussin

The discharge of chromium (VI) and lead (II) into natural streams and rivers from the industries causes several health and environmental problems. Removal of chromium (VI) and lead (II) from aqueous solution by sawdust activated carbon as compared with commercial activated carbon was studied. In this study, sawdust has been treated with phosphoric acid to form activated carbon and used to remove chromium (VI) and lead (II). The application of it will reduce solid waste disposal problem and also minimize the cost of wastewater treatment. The optimum parameters that has been investigated are initial concentration, pH, adsorbent dose and contact time. Sawdust activated carbon has ability to remove Cr (VI) and Pb (II) from the aqueous solutions with the percentage removal is 60-80% for Cr (VI) and 90-100% for Pb (II). The maximum percentage removals were found at 2 ppm of aqueous initial concentration, pH 2 for chromium (VI) and pH 6 for lead (II). The result of this study also showed that, the optimum adsorbent dose of sawdust activated carbon was 2.4 g for the removal of Cr (VI) at 80 minutes while 1.6 g for the removal Pb (II) at 60 minutes. The removal of Cr (VI) and Pb (II) are more efficient by using commercial activated carbon compared with sawdust activated carbon due to its greater percentage removal but sawdust activated carbon can be considered as good adsorbent due to the sawdust that can be easily obtained and its low cost.