Preparation of Silver/Chitosan Nanocomposite for Water Decolorization

Silver nanoparticles are important antibacterial substances which are very attended to be prepared and employed in various field. This study aimed to prepare silver nanoparticles with chitosan biopolymer coating having well known adsorptive property to remove acid orange 7 dye from water. To lessen the number of experimental runs as well as to find the optimal conditions, the experimental design method was used. The performance of prepared adsorbent within the temperature range of 25-60°C, feed concentration of 8-50 mg/l, and 5-120 min contact time was examined. According to the results, the adsorption depended on dye concentration in feed solution; however, the temperature was not affecting parameter within the examined temperatures. Predictably, by increasing the contact time the dye adsorption increased and the equilibrium adsorption depended on contact time. The maximum adsorption capacity of the modified adsorbent was 37.5mg/g. The reaction kinetic agreed with the pseudo-second-order equation and the dominant adsorption mechanism was found to be Freundlich isotherm approving chemical sorption. Silver nanoparticles offered lower dye adsorption (around 0.15mg/g) relative to silver/chitosan nanocomposite implying the effectiveness of the applied improvement method.