Kinetic Modeling and Isotherm Studies on Removal of Methyl Orange from Aqueous Solutions Using Guar gum Powder

摘要

In this paper, the potential of guar gum powder was investigated as a low cost and eco-friendly biosorbent for the removal of methyl orange dye from aqueous solutions. The adsorption behaviour of the biosorbent was investigated by performing equilibrium isothermal studies in batch conditions at 34 °C. During study the adsorption conditions for the adsorbent were calculated by changing different experimental parameters i.e. contact time, initial dye concentration, adsorbent dose, particle size and pH of the solution. The adsorption studies were best fit with Langmuir isotherm as compared to Freundlich and Temkin isotherms. According to Langmuir model the monolayer adsorption capacity found to be 45.45 mg/g at pH 4.2 at 34 °C. The correlation coefficient value indicate a moderate fit for monolayer Langmuir model (R~2 = 0.96). The q_e experimental and calculated values for the pseudo-second-order kinetic model was in good agreement as compared to that by pseudo first order kinetics (R~2 >0.99). The structural characterization of guar gum powder was done by scanning electron microscopy.