ADSORPTIVE REMOVAL AND KINETIC MODELLING OF COLOUR, TURBIDITY, AND COD FROM SLAUGHTERHOUSE WASTEWATER USING BIOSYNTHESIZED SILVER NANOPARTICLES FROM AQUEOUS EXTRACT OF PINEAPPLE PEEL (Ananas Comosus)

This study investigates the adsorptive removal and kinetic modelling of colour, turbidity, and chemical oxygen demand (COD) from slaughterhouse wastewater (SWW) using silver nanoparticles (AgNPs) biosynthesized from the aqueous extract of pineapple peel (Ananas comosus); designated AgPPE. AgPPE were synthesized, characterized by UV–Vis spectroscopy, Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), and Brunauer–Emmett–Teller (BET) surface area analysis. TEM revealed spherical nanoparticles of a mean diameter of 14.62 to 17.63 nm; XRD confirmed face-centred cubic metallic silver; The surface area of the BET was 449.842 m2 / g. Batch adsorption experiments were conducted, achieving adsorption efficiencies of 75.18% (Colour), 72.94% (Turbidity), and 71.27% (COD). Pseudo-second-order kinetic modelling provided the best fit (R² ≥ 0.9997), indicating chemisorption as the dominant mechanism. Intraparticle diffusion was involved but was not the sole rate-controlling step, as confirmed by Boyd plot analysis. The findings demonstrate that biogenic AgPPE is an effective, low-cost, and eco-friendly nanomaterial for the remediation of slaughterhouse wastewater.