ABSTRACT Environmental pollution poses a significant threat to ecosystems and human health, making effective solutions for pollutants. Adsorption has emerged as a promising, efficient, and sustainable method for tackling this challenge due to its effectiveness and environmental benefits. This study investigated activated carbon (AC) derived from Psidium guajava (guava) peel waste using a chemical activation method to evaluate its effectiveness in removing cationic methylene blue (MB) dye and 4‐nitrophenol (4‐NP). The AC was thoroughly characterized using X‐ray diffraction (XRD), scanning electron microscopy (FE‐SEM), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET), zeta potential, and Fourier transform infrared spectroscopy (FTIR) to understand its structural and surface properties. Adsorption studies were conducted using MB as the target pollutant, focusing on adsorption kinetics and equilibrium behavior. The results demonstrated a remarkable 98.7% removal efficiency of MB within 10 min. Kinetic studies revealed a pseudo‐second‐order ( R 2 = 0.99), while the adsorption isotherms were described by the Langmuir model ( R 2 = 0.94), indicating monolayer adsorption. Additionally, the AC achieved a 53% removal efficiency for 4‐NP, demonstrating that activated carbon is a potential candidate for dual functionality in the removal of dye and 4‐NP compounds. This suggests that AC is a cost‐effective adsorbent for the removal of pollutants.
Murugesan et al. (Thu,) studied this question.