Synthesis of silver nanoparticles using Pongamia pinnata leaf extract for efficient removal of acid Brilliant Red 3BN dye under solar irradiation.

The degradation of dye in effluent from textile industries is a vital area of research for mitigating the effects of the dyestuff on the ecosystem. In this study, silver nanoparticles were synthesized using a green approach using Pongamia pinnata leaf extract as a natural reducing and capping agent. The leaf extract and synthesized silver nanoparticles (AgNPs) were characterized for identifying the active functional groups and UV absorbance. Further, the surface morphology, particle-size distribution, and elemental analysis of the silver nanoparticle were characterized. The photocatalytic studies of the synthesized AgNPs were done for acid dye – acid Brilliant Red 3BN under solar irradiation. The process variables like the dye concentration, contact time, catalyst concentration, and pH were analyzed by one factor at a time approach. The formation of silver nanoparticles from silver nitrate by P. pinnata leaf extract was evident at 432 nm. The average particle size was found to be 50 nm and the shape of the silver nanoparticle was spherical. The elemental analysis confirms the presence of silver nanoparticles. The optimum factors are 5 ppm of dye concentration, and 10 mg/L catalyst concentration with a reaction time of 2 h at pH 4 for achieving photocatalytic degradation of 74% of acid Brilliant Red 3BN dye. The kinetic studies reveal that the reaction showed a good fit for the first-order kinetics with a rate constant of 0.00577 min–1 with R2 value of 0.97629. This study confirms the green synthesis of silver nanoparticles and its effective degradation of acid Brilliant Red 3BN dye. [ABSTRACT FROM AUTHOR]