Comparison among O3, PAC adsorption, O3/HCO3-, O3/H2O2 and O3/PAC processes for the removal of Bomaplex Red CR-L dye from aqueous solution

Abstract

Various processes including O-3, powder activated carbon (PAC) adsorption, O-3/HCO3-, O-3/H2O2 and O-3/PAC were used in order to remove dye and chemical oxygen demand (COD) from synthetic wastewater containing Bomaplex Red CR-L dye in a semi-batch reactor. These processes rapidly removed the dye and COD from dye solution. The dye removal efficiency was over 99% for a reaction period of 30 min for all the processes. It was observed that PAC adsorption and O-3/PAC processes were considerably more effective than ozonation process for the removal of COD from dye Solution. The COD removal efficiency of O-3/PAC was higher than PAC adsorption process. O-3/PAC process was considerably effective to remove COD from dye solutions despite using less amount of PAC (approximately four times less than one used for PAC adsorption) for the same amount of COD removal with a higher efficiency. O-3/HCO3- process positively affected the COD removal efficiency, whereas O-3/H2O2 process negatively affected the COD removal efficiency as compared to the ozonation process alone. In addition, the yield and mechanisms of dye removal were also explained on the basis of the results of Fourier transform infrared spectroscopy (FTIR). It was concluded that the O-3/PAC process is a highly efficient process to remove dye and COD from synthetic textile wastewaters as compared to the other processes. (c) 2006 Elsevier Ltd. All rights reserved.