Removal of methylene blue dye by using synthesised Grevillea robusta silver nanoparticles and optimisation of experimental parameters by response surface methodology (central composite design).

Wastewater containing dye is usually treated by physical, chemical or biological treatment processes. Adsorption process is one of the effective and efficient techniques that have been successfully employed for colour removal from wastewater. The aim of the present study is to remove methylene mlue (MB) dye from its aqueous solution using Grevillea robusta silver nanoparticles (GR-Ag-NPs) as adsorbent. The variables covered were contact time, solution pH, adsorbent dosage, initial dye concentration and temperature. The adsorbents were characterised by using scanning electron microscopy (SEM), for its surface functional groups using Fourier Transform Infrared Spectroscopy (FTIR); furthermore response surface methodology (RSM) was adopted to study the correlations among the process variables affecting the process and to optimise the process to give higher % dye removal. [ABSTRACT FROM AUTHOR]