Enriched removal of cationic and anionic dyes using 4-nitro cinnamaldehyde loaded hydroxyapatite with hematite nanocomposites

Abstract

The inadvertent release of dyes from the industrial manufacturing sector has significantly affected water ecosystems. The pollution of water bodies with harmful dyes has direct and indirect consequences, disrupting the entire biosphere. This study evaluated a novel adsorbent material (4NC-PVP-HAp-FeO nanocomposite) designed to remove anionic and cationic dyes from aqueous solutions. The investigation targeted the adsorption efficiency of this synthesized material in decontaminating water polluted with Congo red (CR) and methylene blue (MB) dyes at room temperature. The 4NC-PVP-HAp-FeO nanocomposite was characterized using various instrumental techniques. A comprehensive examination of the factors influencing the adsorption equilibrium was conducted under optimized conditions. Fitting the experimental data to various models revealed the Langmuir isotherm and pseudo-second-order kinetics to be the extremely fit for explaining the adsorption isotherm and kinetics mechanism, respectively. In particular, the maximum monolayer adsorption capacity (Qmax= 156.56 mg) for methylene blue adsorption highlighted the superior performance of the absorbent. In addition, the 4NC-PVP-HAp-FeO nanocomposite was easily retrievable and reusable for up to five cycles. As a result, the characterization and experimental findings affirm the potential application of the 4NC-PVP-HAp-FeO nanocomposite in effectively decontaminating wastewater.