Mesoporous fibrous Nanosilica (KCC-1) supported Polyaniline composite: Synthesis, characterization, and dye removal assessment in simulated and real water samples

Abstract In this work, polyaniline (PANI) functionalized fibrous porous silica nanoparticles (KCC-1 NPs) namely KCC-1/PANI nanocomposite with excellent surface area (391.34 m2/g) and adsorption capacities have been successfully developed by the hydrothermal method followed by the in situ polymerization technique. KCC-1/PANI has been characterized using FE-SEM, FTIR, XRD, TGA-DTA, BET, and Zeta potential analyses and their adsorption property has been screened out against several dyes. The morphological characterization shows wrinkle shaped, fibrous type KCC-1 NPs. According to the TGA results, KCC-1/PANI withstands the temperature upto 470 ℃ with weight loss of only 35%. The adsorption capacities of PANI, KCC-1 and KCC-1/PANI nanocomposite for CV uptake at neutral pH was evaluated. The qmax of KCC-1/PANI against CV adsorption was 456.62 mg/g (obtained from Langmuir model). Adsorption mechanism investigation disclosed that the sorption of CV dye onto KCC-1/PANI was ascribed because of π-π and electrostatic interactions, and hydrogen bonding (dipole-dipole interaction and Yoshida bonding) between hydrogen containing functional groups (hydroxyl and amine) of the KCC-1/PANI nanoadsorbent and CV molecules. Adsorption process strictly fulfilled pseudo second order kinetic model with R2 (0.998) and closeness between qecal (1428.57 mg/g) and qeexp (1417.14 mg/g). Thermodynamic studies revealed that the CV abatement using KCC-1/PANI is endothermic process with ΔH° = 9.11 kJ/mol and spontaneous as value of ΔG° is negative at all temperatures (ΔG° = -9.29 to -11.15 kJ/mol). Batch adsorption operations were also confirmed to validate the ability of the KCC1-/PANI nanoadsorbent to adsorb CV dye from real wastewater, including tap water, river water, and laundry wastewater. Hence, this study reflecting that KCC-1/PANI nanoadsorbent could be an exquisite material for the mitigation of cationic dye pollutants from aqueous environment.