Green Synthesis and Characterization of α-Fe2O3 Nanoparticles using Leaf Extract of Syzygium cumini and their Suitability for Adsorption of Cu(II) and Pb(II) Ions

Abstract

In the present study, we have synthesized α-Fe2O3 nanoparticles by using the leaf extract of Syzygium cumini. The applying green synthetic process is very efficient, low cost and can be applicable in the large scale operations. The freshly synthesized dried nanoparticles were characterized by UV-visible, FT-IR, XRD and FESEM. The α-Fe2O3 (haematite) nanoparticles have now used as effective nano-adsorbents for the removal of Cu(II) and Pb(II) ions from synthetically prepared wastewater under batch conditions. The batch system included contact time, dosage, pH, concentration and temperature. The maximum adsorption efficiency was found at optimized conditions such as contact time 60 min, higher acidic pH 6, higher dosage of sorbent 1.0 g and lower metal ion concentration 10 mg/L. For Pb(II) ions, 59.79, 85.10, 51.39 and 36.81 % adsorption was found at contact time 60 minutes, pH 6, dosage 1 g and metal ion concentration 10 mg/L. Similarly, for Cu(II) ions at same conditions, the adsorption was found to be 49.88, 69.73, 53.77 and 20.68 %, respectively. The equilibrium data of adsorption have been tested by Langmuir, Freundlich and Temkin isotherm models. The adsorption data were best fitted to Langmuir isotherm model with the regression values R2 = 0.984 for Cu(II) ions and R2 = 0.9383 for Pb(II) ions. The adsorption capacity of α-Fe2O3 nanoparticles for Cu(II) and Pb(II) ions was found 7.535 and 6.480 mg/g, respectively.