Synthesis and characterisation of PANI- coated Heliotrope Leaves (PANI@HL) with high clean-up capacity for Orange G dye from aqueous media

The main objective of this study is to optimise a new composite for the depollution of contaminated water. This pollution can have adverse effects on both human health and the environment. The aim of this work was the elaboration and characterisation of a Novel polyaniline composite with plant leaf powder of Heliotrope (PANI@HL) for the removal of Orange G dye in an aqueous media. Hence, the physicochemical and morphological composition of PANI@HL were characterised by field-emission-scanning-electron-microscopy (FE-SEM), X-ray energy dispersive spectroscopy (EDS) and Fourier transforms infrared (FT-IR) spectroscopy. In addition, the adsorption in a batch system for OG dye adsorption onto PANI@HL material was studied. Therefore, we accomplished a parametric study of the adsorption by studying the effect of several important parameters on the decolourising power of the used material, namely, the pH of the solution, contact time, initial concentration of the adsorbate, adsorbent dosage and temperature. The experimental results were analysed by the Freundlich and Langmuir models of adsorption. Experimental results disclose that the pseudo-second-order model provided a good depiction of the whole kinetic experimental data more than that of Lagergren first-order model, and the maximum monolayer adsorption capacity was 242.39 mg.g(-1) for PANI@HL. In addition, the adsorption data were well fitted with Langmuir isothermal model. The developed PANI@HL material demonstrated good reusability up to four regeneration cycles. These findings revealed that the as-prepared composite PANI@HL, has the potential to be employed as a low-cost adsorbent for the adsorption of orange G from aqueous media.