Plant Gum Synthesized Phytogenic Silver and Palladium Nanoparticles Towards Decolourization of Rhodamine B and Methylene Blue Dyes

Abstract

Nanoparticles have gathered significant attention in current years for their versatile applications, including their use as catalysts for dye decolourization. Rhodamine B (RB) and methylene blue (MB) are common dyes employed in pulp, paper, textile, paint, pharma and other industries and their decolourization is essential to prevent environmental pollution. In this context, silver nanoparticles (Ag NP) of 5 nm and palladium nanoparticles (Pd NP) of 7 nm size were produced utilizing plant gum kondagogu as a reducing and stabilizing agent by pressure cooker autoclaving at optimal conditions. The synthesized NP were utilized as catalysts for the decolourization of RB and MB with sodium borohydride. The effect of varying concentration levels of Ag NP (0.5–5 µg/mL), Pd NP (0.025–0.3 µg/mL) and RB (2.5–7.5 µg/mL) and MB (5–15 µg/mL); and reaction time (1–8/0.25–2 min) was investigated at ambient conditions. Ag NP and Pd NP showed corresponding rate constant (k) values of 0.189 min−1 and 0.367 min−1; and 0.111 min−1 and 0.304 min−1 towards RB and MB, receptively. Efficient catalytic action is attributed to smaller particle size and exceptional stability of NP. Thus, the decolourization capability of NP can have wide functions in the ecofriendly ecological remediation of diverse wastewaters contaminated with noxious, mutagenic, carcinogenic, dangerous dyes and pigments.