Cd (II) removal from aqueous solution by Eleocharis acicularis biomass, equilibrium and kinetic studies
Por:
Miretzky, P, Munoz, C, Carrillo-Chavez, A
Publicada:
1 abr 2010
Resumen:
Batch experiments were carried out to determine the capacity of Eleocharis acicularis biomass to adsorb Cd(2+) ions from contaminated solutions with respect to pH, initial Cd(2+) concentration, contact time, solution ionic strength and biomass dose. The experimental data were modeled by Langmuir, Freundlich and Dubinin-Radushkevich (D-R) isotherm models. Freundlich and D-R models resulted in the best fit of the adsorption data. The maximum adsorption capacity for Cd(2+) was 0.299 mmol g(-1) (33.71 mg g(-1)) with efficiency higher than 80% (pH 6.0 and 5 g L(-1) biomass dose). The mean adsorption free energy value derived from the D-R model (8.058 kJ mol(-1)) indicated that adsorption was governed by an ionic exchange process. The pseudo-first order, pseudo-second order, Elovich kinetic models and the intra-particle diffusion models were used to describe the kinetic data and to evaluate rate constants. The best correlation was provided by the second-order kinetic model, implying that che
Filiaciones:
Miretzky, P:
Univ Nacl Autonoma Mexico, Ctr Geociencias, Queretaro 76230, Mexico
Munoz, C:
Univ Nacl Autonoma Mexico, Ctr Geociencias, Queretaro 76230, Mexico
Carrillo-Chavez, A:
Univ Nacl Autonoma Mexico, Ctr Geociencias, Queretaro 76230, Mexico
|