Sustainable Dye Removal Applications of Activated Carbon Derived From Albizia Lebbeck Bark

ABSTRACT

Industrial dye pollution poses a serious threat to aquatic ecosystems and public health, necessitating the development of efficient and sustainable remediation strategies. In this study, a biomass‐based adsorbent was prepared from Albizia Lebbeck bark using KOH‐assisted chemical activation. The resulting activated carbon (AC) was characterized by XRD, XPS, and FESEM analyses. FESEM revealed an irregular mesoporous carbon morphology with granular surface features, while an XRD diffraction feature of AC centred at around 2 θ  = 25.4° was observed, which can be assigned to the (002) reflection of carbonaceous materials. XPS peaks at ∼285.38 and 287.68 eV correspond to sp ² /sp ³ hybridized carbon (─C─C─/─C═C─) of activated carbon. Batch adsorption studies were performed to evaluate the removal efficacy of methylene blue (MB) and malachite green (MG) from aqueous solution. The maximum dye removal efficiencies were 99.7% for MB and 99.9% for MG at an adsorbent dose of 0.4 g. Adsorption isotherm analysis showed that the Langmuir model provided a better fit than the Freundlich model, with correlation coefficients of 0.978 for MB and 0.941 for MG, indicating predominantly monolayer adsorption on a relatively homogeneous surface. The Freundlich parameter 1/n suggested favorable adsorption for MB (0.241), whereas the value obtained for MG (1.246) indicated less favorable adsorption behavior. Kinetic studies showed that the adsorption process followed a pseudo‐second‐order model.