Utilization of Agricultural Waste as Low-Cost Adsorbents in Dye Wastewater Treatment: Kinetic and Thermodynamic Study

Abstract In recent years, the treatment of dye wastewater has attracted more attention because its harmful impact on environment. Therefore, should be treated using effective methods, such as adsorption, which is widely employed to remediate many dyes from wastewater. This work studied use Laurus Nobilis Leaves (LNL) and sawdust (SD) low-cost natural adsorbents reactive blue (RB) synthetic under influence their dosages (0.5-5.5 g) for each, pH (3-9), contact time (10-190 min). The experimental design, analysis results, optimization were conducted Response Surface Methodology (RSM) based Box-Behnken method (BBM) Minitab-Statistical program. BET FT-IR tests have been used characterize these adsorbents, show that SD-adsorbent includes pore volume surface area than LNL-adsorbent. adsorption isotherms study revealed Langmuir isotherm was a fitted model Freundlich model. Adsorption kinetic shows current process obeys pseudo-second order (R 2 =0.998) compared pseudo-first =0.973) intraparticle diffusion =0.915). Thermodynamics present endothermic, random irregularity at solid-liquid, spontaneous nature. More 60% RB-dye removal efficiency achieved optimal conditions, 5.5 g SD-adsorbent, 0.8 LNL-adsorbent, 3, 141 min time. core results proved interaction effect multi-natural significant cost-effective, providing considerable