Synthesis and adsorption applications of PPY/Fe3O4 nanocomposite based material

Abstract

The present study deals with the synthesis of an efficient Polypyrrole/Fe3O4 (PPY/Fe3O4) nanocomposite based material and its utilisation in the adsorptive removal of Pb (II), Cd (II) and Zn (II) ions. The synthesised PPY/Fe3O4 nanocomposite based adsorbent has been characterised by means of FE-SEM (Field emission scanning electron microscope), EDX (Energy dispersive X-ray), P-XRD (Powder X-ray diffraction) and FTIR (Fourier transform infra-red) techniques. The characteristic FTIR peaks were found at 3427 cm−1, 1618 cm−1, 1395 cm−1, 1086 cm−1, 1180 cm−1, 525 cm−1and 453 cm−1 and indicating the presence of N–H, C=N, C–O, C–N, C–C, C–Fe, Fe–O etc bonds on the surface of PPY/Fe3O4 nanocomposite. Adsorption of selected heavy metal ions on the surface of PPY/Fe3O4 was done by applying different adsorption parameters. The removal (%) of lead, cadmium and zinc ions was found to be 69.1%, 62.1% and 53.9% at 60 min, 54.9%, 51.9% and 36.9 at 1 g of PPY/Fe3O4 and 96.2%, 83.9% and 89.9% at pH 6, respectively. The suitability of adsorption process, mechanism and rate of adsorption has been observed using different isotherm and kinetic models. The maximum adsorption capacities (Kla) have been evaluated for lead, cadmium and zinc ions using Langmuir model as 11.350, 8.928 and 7.107 mg g−1, respectively. The values of pseudo first order rate constants (k1) for Pb (II), Cd (II) and Zn (II) ions on PPY/Fe3O4nanocomposite were found to be -0.644 min−1, -0.694 min−1and -0.563 min−1, respectively. The pseudo second order rate constants were calculated for lead, cadmium and zinc ions as 1.122, 0.816 and 1.004 g mg−1 min−1, respectively.