| Autor: |
Bagtache, R., Khelifati, N., Slimani, H., Abdmeziem, K., Trari, M. |
| Zdroj: |
Chemistry Africa; March 2020, Vol. 3 Issue: 1 p161-170, 10p |
| Abstrakt: |
The vanadotungstate K7V5W8O40·12H2O synthesized by hydrothermal route at 453 K was reported for the first time. The compound crystallizing in a Keggin type structure was characterized by powder X-ray diffraction, FTIR spectroscopy and UV–Vis diffuse reflectance; it was successfully tested for the removal of Rhodamine B (Rh B). The effects of contact time, initial concentration and pH were investigated. The adsorption capacity reached ~ 40% in aqueous solution within 16 h. Pseudo-first-order, pseudo-second-order, Elovich and intra-particle diffusion models were applied to fit the experimental data. The pseudo-second-order was the best to describe the adsorption. The equilibrium isotherms were also analyzed by different models. Negative free enthalpy (ΔG) suggested that adsorption Rh B is spontaneous. The positive enthalpy (ΔH) entropy (ΔS) indicated endothermic process with an increase in the randomness of the solid/liquid interface. The compound showed 42% degradation of the remaining concentration after 4 h exposure to solar radiation. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
|
Full text from SpringerLink