Use of sequential Fe2O3-powdered activated carbon/activated sludge process to remove reactive black 5 and chemical oxygen demand from simulated textile wastewater

In this study, the sequential use of maghemite (Fe2O3) coated powder activated carbon (MAC) and activated sludge process (AS) to remove of Reactive Black 5 (RB5) and chemical oxygen demand (COD) from simulated textile wastewater was investigated. MAC can be effectively separated from the liquid phase due its magnetic properties. The effect of MAC and Mixed Liquor Suspended Solids (MLSS) concentration on the RB5 and COD removal were investigated. Experimental studies showed that the sequential MAC/AS process has high efficiency in the RB5 and COD removal from textile wastewater. The adsorption capacity of MAC for RB5 was determined as 143.6 mg/g. The Koble-Corrigan isotherm successfully described the adsorption process. In the adsorption stage of the sequential MAC/AS process, complete removal of RB5 was achieved with 3.75 g/L MAC. In the second stage, it was determined that the approximately 99% of total COD removal was obtained with activated sludge containing 3000 mg/L MLSS.