Application of Lignocellulosic Aerogels Derived from Rice Straw for Adsorption of Acidic Dye from Water

Conversion of agricultural wastes to valuable products is one of the sustainable method to prevent air pollution thet arises from biomass open burning. One of these new and valuable products are lignocellulosic aerogels, which due to their superior characteristics, such porous structure and large surface area can be used for removal of various pollutants such as dye. In this study, lignocellulosic aerogel obtained from rice straw were used to remove the Acid Orange 7 (AO7) from water and the effect of absorption process parameters on adsorption were investigated. The results demonstrated that the efficiency of adsorption greatly influenced by solution pH and temperature. For various concentrations of dye, the equilibrium was reached at 120 minutes. Isotherm data were well adapted to the Langmuir model and maximum adsorption capacity estimated from linear Langmuir was 52.1 mg/g that was approximately twice of the rice straw adsorption capacity. The kinetics results well interpreted by pseudo second order mode, indicating chemisorption as the rate-limiting step which correspond to the interactions between the active sites of aerogel surface and the functional groups of dyes.