Removal of congo red from aqueous solution using kenaf core fiber

Removal of Congo red dye from aqueous solution was studied in batch mode by using kenaf core fiber as low-cost adsorbents. The adsorption process is used because it is found to be more economical and effective compared to other dye removal methods. In this study, kenaf core fiber with size of 0.125 mm was used. Fourier Transform Infrared spectroscopy (FTIR) analysis revealed that functional groups such as OH, and amine on kenaf core fiber proved that it can be used as adsorbent for removal of Congo Red. Then effective parameters include particles size of adsorbent, adsorbent dose, pH, and initial dye concentration versus contact time on adsorption by kenaf core fiber was investigated. In addition, isotherms and kinetics adsorption studies were employed for determination of the equilibrium adsorption capacity and reactions dynamics, respectively. The well fitted model was the Freundlich isotherm with R2 of 0.9995. This indicates that the adsorption that took place is a multilayer adsorption. The highest percentage removal of Congo red dye was found at 97.81% and it is proven that raw kenaf core fiber is potential to remove Congo red dye. The kinetic studies of the adsorption of Congo red dye were carried out by using the pseudo-first and pseudo-second-order kinetic models. Moreover, in this study, the adsorption of Congo red dye onto the kenaf core fibers were well fitted by the pseudo second-order model with regression coefficients higher than 0.99.