Fabrication of Polyaniline‐Supported MnO2 Nanocomposite for Removal of Water Pollutant: Kinetic and Isotherm Studies.

In the present work, we have successfully developed polyaniline supported manganese dioxide (PANI/MnO2) nanocomposite using a facile and inexpensive approach under mild and green conditions by the PANI nanofiber sacrificial oxidation induced reductive conversion of KMnO4 as MnO2. The developed PANI/MnO2 adsorbent material was efficiently utilized for the removal of an organic dye Toluidine Blue (TB) from the aqueous samples.The fabricated adsorbent material was composed of the microstructures that possess grainy and fibrous morphology, and highly uneven surface textures. The FTIR, EDS, and XPS results show the presence of Mn, O, C, and N elements in the nanocomposite. Additionally, from XPS data the survival of the Mn+4 valance state of manganese was recognized. The nano‐thread deposited nano‐fibrous mesoporous nanocomposite holds a high BET surface area (168.096 m2 g−1), and pore volume (0.4428 cm3 g−1).The batch adsorption equilibrium studies showed that 97.51 % of the TB dye was eliminated in 70 min of sorption equilibrium at neutral pH with 92 mg/g of adsorption capacity. The kinetics of the adsorption process is finely portrayed by the pseudo‐second‐order (PSO) kinetic model and the adsorption mechanism is found to be concurrently controlled by intraparticle (IP) and film diffusion (FD) processes. The adsorption isotherm analysis studies revealed that the adsorption of TB dye over the developed PANI/MnO2 adsorbent material occurred with coverage of energetically equivalent binding sites by monolayer formation as substantiated by Langmuir isotherm. [ABSTRACT FROM AUTHOR]