Servicios Personalizados
Revista
Articulo
Indicadores
- Citado por SciELO
- Accesos
Links relacionados
- Citado por Google
- Similares en SciELO
- Similares en Google
Compartir
Tecnura
versión impresa ISSN 0123-921X
Resumen
AMARINGO VILLA, Fredy Alberto y DEL SOCORRO, Angelina. Adsorption of red 40 dye on rice husk: determination of the equilibrium, kinetic and thermodynamic of the process. Tecnura [online]. 2018, vol.22, n.56, pp.13-28. ISSN 0123-921X. https://doi.org/10.14483/22487638.12961.
Context:
Agricultural residues have become unconventional adsorbents of great interest due to their wide availability, minimum cost, and high efficiency. In this work, the adsorbent capacity of rice husk by-product (RH) in the Red 40 (R40) anionic dye removal was evaluated under a discontinuous system.
Method:
For determining the best conditions for the removal of this dye, a factorial design 23 was implemented, which allows to achieving a removal of 75.6% at pH = 2.0, an initial concentration of 15 mg/L, dosage of 8.0 g/L, and contact time of 18 hours.
Results:
The equilibrium, kinetics and thermodynamic properties of the process were evaluated. It was found that the Langmuir model best represents the experimental results with q max of 2.74 mg/g and an adjustment coefficient of R2=0.987. Regarding kinetics, the pseudosecond order model with qt of 1.09 mg/g presented the best fit (R2 = 0.970). Finally, Gibbs free energy (ΔG = -1.11 KJ/mol) and entropy (ΔS = 23.9 J/mol*K) indicate a spontaneous process, while enthalpy showed that the removal of R40 constitutes an endothermic process, with ΔH = 6.71 KJ/mol. Furthermore, the activation energy of 14.1 KJ/mol suggests that the mechanism of adsorption of the R40 takes place through a physi-adsorption.
Conclusions:
These results indicate that the rice husk offers a adequate adsorbent capacity for the retention of azo dye off contaminated effluents; besides, scaling up this process is feasible given its thermodynamic characteristics.
Palabras clave : kinetic; azo dye; design of experiments; isotherm; removal; agricultural by-product.