Fabrication of Polyaniline/Poly(Vinyl Alcohol)/Montmorillonite Hybrid Aerogels Toward Efficient Adsorption of Organic Dye Pollutants

Abstract

Three-dimensional (3D) polyaniline/poly(vinyl alcohol)/montmorillonite (PANI/PVAL/MMT) hybrid aerogels with easy separation performance were fabricated by a simple in-situ polymerization method for the removal of organic dye pollutants. The incorporation of MMT particles into aerogel matrix was successfully proven by the energy dispersive spectra mapping and small and wide-angle X-ray scattering. A well-defined hierarchical structure where PANI nanofibers coated on the skeleton wall can be observed for PANI/PVAL/MMT exhibiting the highest specific surface area when the incorporation amount of MMT was around 11.1 wt%. The adsorption performance of as-prepared hybrid aerogels on both anionic and cationic dyes was systemically investigated. While PANI/PVAL efficiently adsorbed anionic dyes, MMT was an efficient adsorbent of cationic ones. The data analysis showed that the adsorption process for PVAL/PANI/MMT aerogel for Reactive Black 5 (RB5), methyl orange (MO) and safranin followed Freundlich isotherm model and the maximum experimental adsorption capacities were found to be 199.8, 251.3 and 57.0 mg g −1 at 25 °C, respectively. Mechanism studies indicated that the electrostatic interaction is the main driving force for the adsorption of dyes. The results demonstrated that the fabricated hybrid aerogel is an efficient adsorbent for the removal of both anionic and cationic organic dyes.

Keywords: Polyaniline, Poly(vinyl alcohol), Montmorillonite, Aerogel, Dye adsorption