Preparation, Characterization and Dye Adsorption/Reuse of Chitosan-Vanadate Films
- 141 Downloads
Chitosan used on dyes adsorption when in film form shows limitations due to its low regeneration capacity. In this work, chitosan films were modified using vanadium ions to improve its regeneration capacity on the dye adsorption. Films were characterized and analyzed by FT-IR, XRD and DSC. Adsorption assays were performed using chitosan-vanadate films (CVF) to remove the Reactive Black 5 dye in aqueous solution. The adsorption was favored by the pH decrease from 8.0 to 4.0. The equilibrium data were best fitted by Langmuir model, with qm of 522 mg g−1 at 298 K. The negative value of ΔH 0 (−9.91 kJ mol−1) showed an exothermic operation and the value of ΔS 0 was positive (0.0705 kJ mol−1 K−1), suggesting an increase in randomness at the solid/solution interface. The kinetics was represented by pseudo-first order model and around 80 min occurred a reduction in the adsorption rates, due to the mass transfer mechanism. The most appropriate eluent to remove the RB5 from CVF was NH4OH 0.01 kg mol L−1. The CVF used to the dye adsorption were regenerated and reutilized five times, and the adsorption capacity was around 80% of the initial value after the last cycle.
KeywordsDye adsorption Equilibrium Film Kinetics Polymers Wastewater treatment
The authors thank CAPES/Brazil (Coordination for the Improvement of Higher Education Personnel) and CNPq/Brazil (National Council for Scientific and Technological Development) for the financial support. The authors too thank CEME-SUL/FURG/Brazil (Electron Microscopy Center of South/Federal University of Rio Grande/RS/Brazil) due to the microscopy images.
- 3.Ali I, Aboul-Enein HY, Gupta VK (2009) Nano chromatography and capillary electrophoresis: pharmaceutical and environmental analyses. Wiley, HobokenGoogle Scholar
- 4.Khan TA, Sharma S, Ali I (2011) J Toxicol Environ Health Sci 10:286Google Scholar
- 29.ASTM (2000) Standard test methods for tensile properties of thin plastic sheeting. Standard D882-02, Annual book of ASTM, pp 162–170Google Scholar
- 30.Silverstein RM, Webster FX, Kiemle DJ (2007) Spectrometric identification of organic compounds. Wiley, New YorkGoogle Scholar
- 33.Ruthven DM (1984) Principles of adsorption and adsorption process. Wiley, New YorkGoogle Scholar
- 50.Machado FM, Bergmann CP, Lima EC, Royer B, Souza FE, Jauris IM, Calvete T, Fagan SB (2012) Chem Phys 14:11139Google Scholar