Isotherm and kinetic studies on nano-sorption of Malachite Green onto Allium sativum mediated synthesis of silver nano particles

In this work, enhanced production of silver nano particles (AgNp) by green synthesis was carried out using Response Surface Methodology (RSM). The parameters viz., temperature, concentration of plant extract, silver nitrate concentration and pH were optimized for enhancing the production of nano particles. Characterization studies were carried out to study the changes in color during the formation of nanoparticles using UV-Vis spectrophotometer. The morphological study of the synthesized silver nanoparticles was done using Scanning Electron Microscope analysis (SEM). Fourier Transform Infrared spectroscopy (FTIR) was carried out to determine the presence of functional groups in them. The synthesized nano particles, was utilized for the decolourization of Malachite Green (MG) dye. The process variables such as nano particle dosage, pH and temperature were optimized using RSM for the decolorization of MG dye solution. At the optimized conditions, the effect of MG dye concentrations and contact time was studied. From the results it was observed that the synthesized silver nano particles readily decolorizes MG dye. At the optimized condition, maximum removal of more than 90% of MG dye occurs. From the equilibrium and kinetic studies, it was found that the Langmuir isotherm and Intra particle diffusion fits the data well when compared to other isotherms and kinetic model respectively.