Catalytic Degradation of Azo Dyes by Silver Nanoparticles

Abstract

The high industrial demand generates an increased consumption and a high waste of materials that impacts the environment in different spheres. One of the most affected environments are aquatic systems. Moreover, one of the most common forms of water contamination is the improper disposal of dyes by industries such as textiles, cosmetics, and pharmaceuticals. These dyes are organic substances that can give color to a substrate through chemical affinity. The most commonly used synthetic dyes are the ones containing the azo group, which have been reported as carcinogenic, mutagenic, and genotoxic, causing harm to the environment and living beings. Therefore, the study of methods that contribute to the degradation of these species will contribute to better treatment of polluted aquatic environments. Thus, the main objective of this work was to promote the catalytic degradation of organic dyes, such as Methyl Orange and Congo Red, through silver nanoparticles (AgNPs). For this, AgNPs were synthesized with spherical shapes using two stabilizers (polyvinylalcohol-PVA, and polyvinylpyrrolidone-PVP). Subsequently, the AgNPs were applied for the degradation of organic dyes, with the catalysis analyzed via UV-Vis absorption spectrometry in a maximum time of 40 min. Finally, it was observed that these nanocatalysts were successful in degrading the organic dyes. Thus, AgNPs have the potential to be used as catalysts for wastewater treatment.

Keywords

• Methyl Orange
• Congo Red
• nanocatalysis
• wastewater treatment