Removal of Direct Red 12B Dye from Aqueous Solutions by Wheat Straw: Isotherms, Kinetics and Thermodynamic Studies

Authors

1 Department of Chemistry, Islamic Azad University, Gachsaran Branch

2 Department of Chemistry, College of Science, Shahid Chamran University

Abstract

The goal of this study was to survey the feasibility application of Wheat straw as a low-cost adsorbent for the removal of Direct Red 12B from wastewater. The sub goals of the research were to determine the adsorption kinetic and adsorption isotherm, effects of primary concentration of dye, adsorbent dose, effect of contact time, and effect of pH for the adsorption of dye with WS. The maximum removal of Direct Red 12B was 99% obtained by passing an aliquot of the DR12B solution at pH 2.5 and 0.25 gr WS at room temperature. The effects of different parameters such as pH, dye concentration, amount of adsorbent, adsorbent particle size, temperature were studied. The efficiency of adsorbent was also tested for the removal of dye from Karoon River with 99.8% recovery. The results was showed that WS as an adsorbent is a low cost, potentially efficient and eco-friendly adsorbent for removal of DR 12B from industrial wastewater. It was observed that the pseudo-second-order kinetic model fits better with good correlation coefficient. Based on batch experiments, the adsorption data could be fitted by the Langmuir equation with a maximum adsorption amount of 26.38 mg/g.

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