Herein, a novel polypyrrole-Saccharum munja biocomposite (PP-SM) was utilized for the adsorptive removal of three anionic dyes: Reactive Red 35 (RR), Reactive Orange 107 (RO), and Acid Blue 93 (AB) from their single and multi-component systems at neutral pH. The statistical optimization was performed with the Response Surface Methodology (RSM) to study the interdependent effect of pH, concentration, and adsorbent dosage on the % removal of dyes. The analysis of variance (ANOVA) was evaluated to confirm the adequacy of the model. The model F value for RR (142.20), RO (251.24), and AB (151.59) dye indicates the model to be significant and Coefficient of Variance less than 10% for all the dyes depicts the precise reproducibility of the model. The signal-to-noise ratio for RR (42.963), RO (57.585), and AB (44.883) indicate the adequate signal. Further, the kinetic study revealed the Pseudo-second-order model to the best fit for all dyes. The positive value of ΔH (KJmol−1) for RR (6.379), RO (13.204), and AB (7.118) dye indicated an endothermic adsorption process; and the positive value of ΔSº (Jmol−1K−1) for RR (37.480), RO (45.159), and AB (34.792) indicated the enhanced disorders at the interface of adsorbent and adsorbate. Langmuir model was the best fit for dyes in single component system with a maximum monolayer adsorption capacity (qmax) of RR (144.717 mgg−1) > AB (130.719 mgg−1) > RO (59.206 mgg−1). The synergistic or competitive effects of dyes in binary and ternary systems were assessed by using modified Langmuir model. Moreover, the dye removal mechanism involves electrostatic interactions, H-bonding, and π-π stacking. The regeneration of the spent adsorbent was carried out upto five adsorption-desorption cycles and showed a good removal efficiency for dyes. Thus, PP-SM can be prompted as an efficient and cost-effective biosorbent for the adsorptive removal of contaminants from wastewater.
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