Ime Akanyeti
Cyprus International University, Turkey
Title: Competitive sorption of anionic dyes on CoFe-layered double hydroxide in single and binary solutions
Biography
Biography: Ime Akanyeti
Abstract
The synthetic dyes released by the effluents of various industries result in severe environmental pollution that may cause carcinogenic and mutagenic effects on living organisms. Layered double hydroxides (LDH) were extensively studied as high capacity sorbents for the removal of dyes from water. However, a comprehensive understanding of why one dye is sorbed more than the other still remains unknown. In addition, we know very little how sorption mechanisms scale when more than one dye is present in the solution. In this study, a comparative investigation was performed to evaluate the sorption capacity of CoFe LDH for three different dyes: methyl orange (MO), remazol brilliant blue reactive (RBBR) and allura red (AR). Moreover, to shed light on the competitive sorption mechanisms, the sorption behaviour of CoFe LDH in a binary dye solution of MO and RBBR was elucidated. The results indicated that the sorption affinity of CoFe LDH is the highest for MO (750 mg/g) followed by RBBR (155 mg/g) and AR (~83 mg/g), respectively. Sorption of MO on CoFe LDH is best described by the Freundlich isotherm model whereas the Langmuir model has the best fit for RBBR and AR sorption. Fourier-transform infrared spectroscopy and LDH charge analysis results showed that ion exchange mechanism and electrostatic interactions play important roles in dye sorption. In a binary solution, the mass of MO sorbed was reduced significantly while the mass of RBBR sorbed did not change, which was attributed to the alteration of the electrostatic properties of the LDH after the sorption.