Biosorption of Cd2+, Cu2+, Ni2+ and Zn2+ ions from aqueous solutions by pretreated biomass of brown algae.
In this paper, marine brown algae Laminaria japonica was chemically modified by crosslinking with epichlorohydrin (EC(1) and EC(2)), or oxidizing by potassium permanganate (PC), or crosslinking with glutaraldehyde (GA), or only washed by distilled water (DW). They were used for equilibrium sorption uptake studies with Cd(2+), Cu(2+), Ni(2+) and Zn(2+). The experimental data have been analyzed using Langmuir, Freundlich and Redlich-Peterson isotherms. The results showed that the biosorption equilibrium was well described by both the Langmuir and Redlich-Peterson isotherms. The order of maximum metal uptakes for Cd(2+), Cu(2+) and Zn(2+) was EC(1)>EC(2)>PC>DW>GA, but the uptakes of Ni(2+) are almost the same for these sorbents. Moreover, sorption kinetics has been performed and it was observed that the equilibrium was reached in less than 2h, which could be described by pseudo-first-order kinetic model. The metal adsorption was strictly pH dependent. The optimum pH values of four metals were in the range of 4.3-6.5 for all sorbents, and the optimum solid/liquid ratio was 3.0 g L(-1).
Liu
Yinghui
Y
Key Laboratory of Polyoxometalates Science of Ministry of Education, College of Chemistry, Northeast Normal University, Changchun 130024, PR China.
Cao
Qilin
Q
Luo
Fang
F
Chen
Ji
J