Egg By-Products as a Tool to Remove Direct Blue 78 Dye from Wastewater: Kinetic, Equilibrium Modeling, Thermodynamics and Desorption Properties
Author/s
Murcia-Salvador, Ainoa; Pellicer, José Antonio; Gabaldón, José Antonio; Rodríguez López, María Isabel; Núñez Delicado, Estrella; [et al.]Date
2020-01Discipline/s
Ciencias de la AlimentaciónSubject/s
AdsorptionEggshell
Direct Blue 78
Kinetics
Isotherms
Pulsed light
Abstract
Eggshell, a waste material from food manufacturing, can be used as a potential ecofriendly
adsorbent for the elimination of textile dyes from water solutions. The adsorption process was
evaluated varying factors such as initial dye load, contact time, pH, quantity of adsorbent, and
temperature. The initial dye load (Direct Blue 78) was in the range of 25–300 mg/L. The kinetics of
adsorption were analyzed using di erent models, such as pseudo-first-order, pseudo-second-order,
and intraparticle di usion model. Also, the experimental data at equilibrium were studied using
Freundlich, Langmuir, and Temkin isotherms. The kinetics followed pseudo-second-order, then
pseudo-first-order, and finally the model of intraparticle di usion. The results obtained for data
at equilibrium follow the order: Freundlich > Langmuir > Temkin. The adsorption equilibrium
showed a maximum capacity of adsorption (qmax) of 13 mg/g at pH 5, and using 0.5 g of eggshell.
Dye adsorption was enhanced with in...