AgNPs-AC Composite for Effective Removal (Degradation) of Napthol Green B Dye from Aqueous Solution

Abstract

The main objective of this study is to remove toxic dyes, such as Napthol green B (NGB) from aqueous solution. The synthesized Ag-AC composite showed an excellent photocatalytic activity for the removal of such toxic dye (Napthol green B) under solar irradiation. The Ag-AC composite was prepared by chemical precipitation method. Here, biological waste material (Coccinia grandis peel) was used for the synthesis of composite and activated carbon was prepared from waste biomass material (saw dust). The AgNPs was synthesized using Coccinia grandis peel extract. In the present study, the photocatalytic activities of synthesized AgNPs were investigated. From the photocatalytic studies, it was observed that Ag-AC composite showed better catalytic activity than that of pure AgNPs. This may be explained because of the dual properties of AC. The adsorption property of NGB dye was also studied using Ag-AC composite. From the adsorption study it was observed that only 40% of dye adsorbed within 1 h but in photodegrdation process 97% of dye was degraded within 1 h. Hence it was confirmed that photodegradation process was better than adsorption process for the removal of toxic dye. The probable mechanism action of Ag-AC composite and degraded by-products of dye during photodegradation was also discussed in this article. It was for the first time, we report the catalytic behavior of AgNPs and Ag-AC composite as a photocatalyst for the degradation of NGB dye.