Removal of yellow20 dye from aqueous solution using organo-rice straw: Characteristic, kinetic and equilibrium studies

Abstract

The adsolubilisation of tetradecyltrimethyl ammonium bromide by an adsorbent termed ‘organo-rice straw’ was developed in this research to enhance the decolorization behavior of yellow20 in aqueous solutions. The organo-rice straw was characterized by elemental analysis, Brunauer-Emmett-Teller (BET) method, Fourier transform infrared spectroscopy (FTIR) technique, and scanning electron microscopy (SEM) images. Batch studies were researched to address various experimental parameters such as contact time, the initial pH solution, and initial dye concentration. Results showed that the major contents of yellow20 and organo-rice straw were carbon and hydrogen indicating their hydrophobic natures. The percentage of yellow20 that was removed by the organo-rice straw was 96.01%, higher than the 36.44% removed by the precursor (36.44%). The equilibrium adsorption was reached within 3.0 h and the amount of yellow20 adsorbed was independent of the pH0. The kinetic data were fitted to pseudo-first order, pseudo-second order, and intra-particle diffusion models. Results implied that adsorption of yellow20 by this adsorbent followed the second order kinetic model and the maximum adsorption capacity was found to be 166.55 mg.g-1. Equilibrium isotherms were analyzed by the Langmuir, Freundlich, Temkin, and Dubinin-Radushkevtch isotherms. The Freundlich isotherm described the isotherm data with high-correlation coefficients. The results of the study indicate that organo-rice straw is a potential and active bio-sorbent for the removal of yellow20.