Adsorption of Anionic-Azo Dye from Aqueous Solution by Lignocellulose-Biomass Jute Fiber: Equilibrium, Kinetics, and Thermodynamics Study

The present investigation describes the evaluation of feasibility of lignocellulosic-biomass jute fiber OF) toward adsorptive removal of anionic-azo dye from aqueous solution. Batch studies illustrated that dye uptake was highly dependent on different process variables, pH, initial dye concentration of solution, adsorbent dosage, and temperature. Further, an attempt has been taken to correlate these process variables with dye absorption and was optimized through a full-factorial central composite design (CCD) in response surface methodology (RSM). Maximum adsorption capacity (29.697 mg/g) under optimum conditions of variables (pH 3.91, adsorbent dose 2.04 g/L, adsorbate concentration 244.05 mg/L, and temperature 30 degrees C), as predicted by RSM, was found to be very close to the experimentally determined value (28.940 mg/g). Exothermic and spontaneous nature of adsorption was revealed from thermodynamic study. Equilibrium adsorption data were highly consistent with Langmuir isotherm yielding R-2 = 0.999. Kinetic studies revealed that adsorption followed pseudo second-order model regarding the intraparticle diffusion. Activation parameters for the adsorption process were computed using Arrhenius and Eyring equations. Maximum desorption efficiency of spent adsorbent was achieved using sodium hydroxide solution (0.1 M).