The Study of Using Gold Nanoparticles as an Adsorbent for Water Treatment

Abstract

In this study gold nanoparticles were prepared by wet chemistry method. The source of gold is HAuCl₄ and D- glucose sugar used as a reducing agent and tri sodium citrate used as masking agent. The prepared gold nanoparticles were used to remove the lead ion from the contaminated aqueous solutions. The prepared gold nanoparticles were identified through Transmission Electron Microscope (TEM). The TEM images showed that the average diameters of gold nanoparticles ranged from 50-90 nm and dynamic light scattering (DLS) represented by zeta potential and zeta sizer analyzer device used to examine the stability and size distribution of gold nanoparticles.  The plasmon resonance band for gold nanoparticles was found in the wavelength 530 nm. Various conditions affecting the adsorption process were studied, such as equilibrium time, temperature, acidity function and initial concentration of lead ion. Adsorption increases with increasing temperature, meaning that the reaction is endothermic. The adsorption isotherms of Langmuir and Freundlich were also studied. The Langmuir equation was the most applicable to the studied system. The thermodynamic studies showed that the removal process was spontaneous, and positive values of ΔS ​​indicate for increasing in randomness.