Synthesis and characterization of functionalized nanoparticles for adsorption of organic dye

Full text: Textile and food industries use dyes like a Rhodamine B (RB) in large scale and discard them in industrial effluents causing several damages for aquatic organisms and being extremely harmful to human health [1, 2]. The functionalization of nanoparticle (NP) by polymers is an attractive technology that allows the treatment of effluents with dyes [3]. In this work the synthesis of Fe3O4 NP was carried out by the co-precipitations method, followed by functionalization of this biopolymer (BP) based on soybean oil, (Fe3O4)x(BP)1-x NP, with x = 10% (m/m). For the characterization of NPs were used the techniques of X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR) and Thermal Analysis. The XRD results showed that with the increase of the magnetite content, the peaks referring to the same one are displaced to values bigger than 2θ indicating that the BP is chemically connected to NP, thus corroborating with the results obtained by the FTIR, where it was possible to observe the emergence of new bands. The adsorption capacity of NPs was determined using the batch method with solutions of RB in different concentrations (5.0, 10, 15 and 20 mg/L), and the initial and final concentration of RB were calculated using a UV-vis spectrophotometer. The values of q_max obtained for (Fe₃O₄)0,1(BP)0,9 NP were 2.3, 4.8, 7.2 and 9.4 mg/g, respectively. It was observed that in all concentrations analyzed more than 95% of the dye was adsorbed within 360 min with this sample. For the Fe₃O₄ NP the q_max was 0.5 mg/g for all RB solutions. The results showed that the functionalized NP studied have a great ability to adsorb the RB in aqueous solutions, making this nanomaterial promising for the environmental remediation. References: [1] G. L. Dotto et al., Quim. Nova vol. 34, pp. 1193–1199 (2011) [2] Saruchi and V. Kumar, Arab. J. Chem. vol. 12, pp. 316–329 (2019) [3] M. T. Nakhjiri et al., J. Polym. Environ. vol. 27, pp. 581–599 (2019). (author)