Author(s)

Kshama Parajuli^*, Aravind Kumar Sah, Hari Paudyal^*

Central Department of Chemistry, Tribhuvan University, Kirtipur, Kathmandu, Nepal.

Because of various disadvantages of chemical synthesis processes, these days people are attracting towards green synthesis processes as it is devoid of toxic by-products, cost-effective and eco-friendly. In this study, a simple green synthesis method is applied for the synthesis of magnetite (Fe₃O₄) nanoparticles (MNPs) by co-precipitation of FeCl_3·6H₂O and FeSO_4·7H₂O in the molar ratio of 2:1 using Azadirachta indica leaves extract under nitrogen environment. FTIR, XRD, SEM etc. were used to characterize the synthesized MNPs. Batch adsorption experiments were carried out to determine adsorption equilibrium of As(V) as a function of pH, adsorbent dose, contact time and different initial concentrations. Kinetics results were best described by pseudo-second order model with rate constant value 0.0052 g/(mg·min). The equilibrium adsorption isotherm was best fitted with Langmuir adsorption isotherm model. The maximum adsorption capacity was found to be 62.89 mg/g at pH 2. MNPs showed a high affinity for As(V) and avoids filtration for solid-liquid separation, thus it would be employed as a promising material for the removal of As(V) from water.

Green Synthesis, Magnetite Nanoparticles (MNPs), Azadirachta indica Leaves Extract, As(V) Adsorption

Parajuli, K. , Sah, A. and Paudyal, H. (2020) Green Synthesis of Magnetite Nanoparticles Using Aqueous Leaves Extracts of Azadirachta indica and Its Application for the Removal of As(V) from Water. Green and Sustainable Chemistry, 10, 117-132. doi: 10.4236/gsc.2020.104009.