Treatment of dyeing wastewater by activated carbons derived from municipal sewage sludge

Activated carbons derived from municipal sewage sludge with pyrolusite modification were prepared. The impact of pyrolusite amount on the activated carbons' characteristics was evaluated by methylene blue tests. The results showed that activated carbons modified with certain amount of pyrolusite (ACP) had better performance than the ones without pyrolusite addition. These activated carbons prepared were effective in COD and color removal in treating an industrial dyeing wastewater. The significant increase of mesopores in the adsorbents was identified as the reason. The optimum pH value for dye adsorption was pH = 3.0 and it took a relatively long contact time to reach equilibrium (=8 h). Temperature had no obvious effect on dye removal in this study. The regeneration efficiency for three ACPs after two adsorption/regeneration cycles was above 70%. (C) 2011 American Institute of Chemical Engineers Environ Prog, 2011