DOI: 10.36347/sajb.2014.v02i09.010

Pages: 607-612

This paper investigates the ability of activated carbon produced from water hyacinth to remove methylene blue dye from aqueous solution in a packed bed down-flow column. The experiments were performed with different bed heights (3-9 cm) and using different concentrations (200-300 mg/l) in order to obtain experimental breakthrough curves. The study shows 100% reduction of dye from start of experiment up to 0.42, 5.00 and 10.42 hrs for bed heights of 3, 6 and 9 cm respectively. Zero percentage reduction and highest effluent concentration of 250 mg/l were obtained at 15.83, 27.50 and 33.33 hrs, while half of influent concentration (125 mg/l) and 50% reduction of initial dye concentration (125 mg/l) occurred at the critical time of 11.70, 17.95 and 26.25 hrs for the bed heights of 3, 6 and 9 cm respectively. The volume of dye solution treated to achieve exhaustion concentration was 1.75, 2.70 and 3.60 L for 3, 6 and 9 cm bed heights respectively. Increasing the initial dye concentration from 200 to 300 mg/l results in a decrease in the volume of dye solution treated from 950 to 300 ml at the breakthrough point. When initial dye concentration increased from 200 to 300 mg/l, bed adsorption capacity also increased from 29.11 to 32.24 mg/g.