Sorption Studies on the Removal of Industrial Dye Aniline Yellow From Aqueous Solution Using Surfactant Modified Iron Filings

Abstract

Authors: Comfort M. Ngwu*, Okoche K. Amadi, Augustine C. Egwu and Ebelechi C. Lucy

The potential of iron filings for efficient removal of aniline yellow (a cationic dye) from aqueous solutions was investigated. The iron filings were characterized by XRD, SEM and FTIR techniques. To remove aniline yellow, the surface of the iron filings was modified with sodium dodecyl sulfate (SDS) as an anionic surfactant. Also, the various parameters affecting dye removal were investigated and optimized. Dye adsorption equilibrium data fitted well into Temkin isotherm and Redlich Peterson isotherm. The adsorption process was pH-dependent and the results indicate that the optimum pH for maximum adsorption occurred at pH 8.0 for the modified and pH 6.0 for the unmodified adsorbents having   maximum   removal efficiencies of   95.5 and 82 % respectively. Kinetic studies for aniline yellow adsorption showed rapid sorption dynamics according to the second-order kinetic model, suggesting that chemisorption must have played a major role in the adsorption process. Studies on the effect of temperature showed that adsorption capacity increased with increase in temperature for both adsorbents. The results indicate that, SDS-coated iron filings can be used as a cheap and efficient adsorbent for removal of cationic dyes from aqueous solutions.