Abstract

In this study, the efficiency of the adsorption of anionic dye Direct Red 23 (DR23), nonionic dye Direct Green 97 (DG97) and cationic dye Basic Yellow 28 (BY28) from aqueous solutions onto hollow mesoporous carbon nanospheres (HMCN) was investigated. The adsorbent was characterized by means of XRD, HRTEM, TGA, Raman spectroscopy, FTIR, BET and zeta potential measurements. The influence of dye initial concentration, temperature and pH on DR23, DG97 and BY28 adsorption onto HMCN was investigated. Equilibrium data were analyzed by model equations such as Langmuir and Freundlich isotherms and were best represented by Langmuir isotherm model showing maximum monolayer adsorption capacity 769.2mgg−1, 312.5mgg−1 and 909.1mgg−1 for the DR23, DG97 and BY28, respectively. The experimental kinetic data were analyzed using pseudo-first-order, pseudo-second-order and intraparticle diffusion kinetic models. The adsorption kinetics was best fitted to the pseudo-second-order kinetic model. Thermodynamic parameters, change in free energy ΔG°, enthalpy ΔH°, and entropy ΔS° were also evaluated, indicating that the adsorption of DR23, DG97 and BY28 was spontaneous and endothermic in nature.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.