Synergic effect of Guggul gum based hydrogel nanocomposite: An approach towards adsorption-photocatalysis of Magenta-O

The article is related to sunlight and UV-visible mineralization of harmful magenta-O (FB) dye. The nanocomposite used is a cross linked network of acrylic acid synthesized inside poly(acrylamide) grafted Guggul gum in the presence of UV-visible respondent bismuth ferrite nanoparticles. The synthesis of poly(acrylamide) grafted Guggul gum (Sample I) and synthesizing a crosslinked network inside it (Sample II) involved a two-step synthesis for optimizing various reaction parameters. The maximum % water uptake obtained for polymeric samples I and II was calculated as 1227.78% and 387.97%, respectively. Average particle size of bismuth ferrite nanoparticles was 47.34 nm. The nanocomposite could maximum uptake-mineralize FB dye as 97.3% and 98.8% under sunlight and photochemical reactor, respectively for 500 mg nanocomposite dose in 10 mg/L concentrated FB solution. Dye uptake occurs through ionic interactions. However, mineralization is a consequence of advanced oxidation process involving free radical species (OH center dot and O-2(-).). The overall process of uptake-mineralization resembled second order kinetics and Langmuir theorem (monolayer adsorption). Intraparticle diffusion model gave an idea about the multistep (three steps) process of adsorption. Physico-chemical properties of FB dye got changed after mineralization except for the pH. The maximum uptake-mineralization was observed to be 76.2% after consecutive reuse of the nanocomposite hydrogel for five cycles. (C) 2020 Elsevier B.V. All rights reserved.