Graphene oxide-safranin modified@polyacrylonitrile membranes for water purification: Reuse and mechanism based on theoretical calculations and XPS analysis

Author(s)

Neves, Tauany de Figueiredo ; Camparotto, Natalia Gabriele ; Briao, Giani de Vargas ; Mastelaro, Valmor Roberto ; Dantas, Renato Falcao ; Vieira, Melissa Gurgel Adeodato ; Prediger, Patricia

• Document type: Journal article
• Source: JOURNAL OF WATER PROCESS ENGINEERING; v. 50, p. 17-pg., 2022-10-20.

Abstract

The difficulty in metabolizing and degrading complex dyes containing three or more aromatic rings ascends new alternatives in the treatment of colored water, including adsorption. Despite advances in this area, the adsorption of complex dyes has been little reported. In this work, polyacrylonitrile membranes incorporated with graphene oxide functionalized with safranin dye (hPAN@GO-SF) were applied to remove the complex cationic dyes basic blue 7 (BB7) and basic brown 4 (BB4), and the anionic direct black 22 (DB22) from water. The advantage of using nanoadsorbents immobilized on polymeric membranes is their easy removal after adsorption. Under the best conditions established for dye removal, high adsorption capacities of 1143/1035, 873/799 and 205/148 mg.g(-1) were achieved for BB4, BB7 and DB22 in the single and saline system, respectively. Henry and Temkin's isothermal models best fitted equilibrium experimental data of dyes in single and saline systems, respectively, while the kinetic model of intraparticle diffusion fitted well the empirical data in both systems. Furthermore, hPAN@GO-SF can be used for five consecutive cycles without loss of efficiency for the BB7 dye. Theoretical calculations and post-adsorbed membrane analyses showed that the adsorbent/adsorbate interactions are based on H-bonding, pi-pi and electrostatic interactions. (AU)

• FAPESP's process: 19/07822-2 - Synthesis of new nanoadsorbents, their characterizations and applications in pollutant adsorption in water
• Grantee: Patricia Prediger
• Support Opportunities: Regular Research Grants
• FAPESP's process: 13/07296-2 - CDMF - Center for the Development of Functional Materials
• Grantee: Elson Longo da Silva
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC
• FAPESP's process: 19/25228-0 - Development of new membranes based on graphene oxide for the removal of contaminants in water
• Grantee: Tauany de Figueiredo Neves
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)