Hybrid Polyaniline/Dolomite-Palygorskite Framework For Environmental ‎Remediation: Experimental Design and Molecular-Level Adsorption Interpretation

Abstract

Textile and dyestuff manufacturing industries are recognized as the largest source of water ‎contamination. This study explores the effectiveness of polyaniline@dolomite-palygorskite clay ‎‎(PANi@DPC) hybrid composite for removing the organic contaminant Orange G (OG) from ‎polluted water through adsorption. PANi@DPC composite was analyzed by SEM, EDS, FTIR ‎and XRD techniques. The main findings prove the successful incorporation of PANi on the ‎palygorskite surface. The OG dye adsorption experiments were conducted to assess the effect of ‎the operational parameters. PANi@DPC composite exhibited an impressive removal performance ‎‎(> 97.75%) for OG dye over a broad pH range. Kinetics and isotherm data were adequately ‎simulated by the pseudo-second order and Freundlich models. PANi@DPC composite was ‎effortlessly regenerated and efficiently reused for OG removal. FTIR analysis and ‎thermodynamic parameters suggested that the adsorption mechanism is predominantly mediated ‎by H-bonds and π-π stacking. Response surface methodology was deployed in the investigation ‎of the interactive effects of multiple parameters and optimization of OG removal performance. ‎Advanced statistical physics simulation revealed that the OG adsorption follows multi-anchorage ‎and multi-molecular binding mechanisms. Overall, PANi@DPC hybrid composite can serve as a ‎prospective binder material for cleaning up the OG dye-containing wastewaters.‎