The Optimization and Mechanism of Textile Dye Adsorption on the Surface of Pine Sawdust Biomass: Thermodynamic, Isotherm and Kinetic Studies

Due to increasing problems of freshwater availability and wastewater treatment and management, there is a dire need to control water pollution.A major portion of wastewater is produced through dye contamination from textile industries.In this study, efforts were made to evaluate the renewable, environment-friendly, and biomass-based adsorbent for the effective removal of dyes from aqueous solution.Pine sawdust biomass samples were subjected to adsorption under different parametric studies to optimize the adsorption process efficiency.The maximum adsorption efficiency was observed around 50-60 % under different working conditions.This study demonstrates that the non-linear versions of the PSO and IPD kinetic models were better than the linear forms from the perspective of the dye adsorption mechanism.Comparably, the nonlinear fitting of the Freundlich model yielded lower χ² values and higher R² values than the linear fitting.Positive Gibbs free energy values imply that the adsorption is non-spontaneous and thermodynamically unfavorable at the investigated temperatures.The thermodynamic study shows that the adsorption of BBY onto the PSD adsorbent is an exothermic process.