Adsorption of Safranin-O dye by copper oxide nanoparticles synthesized from Punica granatum leaf extract

• Published in: Environmental technology Vol. 43; no. 20; pp. 3047 - 3063
• Main Authors: Vidovix, Taynara Basso, Quesada, Heloise Beatriz, Bergamasco, Rosângela, Vieira, Marcelo Fernandes, Vieira, Angélica Marquetotti Salcedo
• Format: Journal Article
• Language: English
• Published: England Taylor & Francis 06-09-2022; Taylor & Francis Ltd
• Subjects: Adsorption; Cationic dyes; Color removal; Copper; Copper oxide nanoparticles; Copper oxides; dye removal; Dyes; Ionic strength; Leaves; nanomaterial; Nanoparticles; New technology; Physicochemical analysis; Plant extracts; pomegranate; Punica granatum; Safranin-O; Surface charge; Surface chemistry; Synthesis; Toxicity; Wastewater treatment; Water pollution; Water resources; nanomaterial; dye removal; pomegranate; Copper oxide nanoparticles
• ISSN: 0959-3330; 1479-487X
• DOI: 10.1080/09593330.2021.1914180

The development of new technologies for water and wastewater treatment is a growing need due to the occurrence of micropollutants, such as dyes, in water resources. In this sense, green-synthesized nanoparticles are being extensively studied, due to their low cost, non-toxicity, and high efficiency in adsorption processes. Thus, the present study reports the green synthesis of copper oxide nanoparticles (CuO-NP), obtained from pomegranate (Punica granatum) leaf extract, employed for the removal of Safranin-O (SO) dye. CuO-NP was characterized by physicochemical analysis. These analyzes suggested that the redox process occurred efficiently. Also, the material presented interesting elements for the removal of cationic dyes such as negative surface charge, high specific surface area, and predominance of mesopores. The kinetic data fitted the pseudo-second-order model, reaching equilibrium in 480 min. The equilibrium study resulted in a maximum adsorption capacity of 189.54 mg g
−1
at 298 K and the experimental data best fitted the Langmuir model. The effect of pH and ionic strength did not present significant changes, which demonstrates an advantage of this adsorbent over other materials. The regeneration study allowed to verify the possibility of reuse CuO-NP, since after 4 cycles the adsorption capacity was 44% of the initial value. Considering the results found, CuO-NP has a high potential for applicability in the treatment of water contaminated by dyes.