Zinc and cadmium removal by biosorption on Undaria pinnatifida in batch and continuous processes

PLAZA CAZÓN JOSEFINA; MARISA VIERA; DONATI EDGARDO; GUIBAL ERIC

JOURNAL OF ENVIRONMENTAL MANAGEMENT

ACADEMIC PRESS LTD-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2013

0301-4797

Zn(II) and Cd(II) removal by biosorption using Undaria pinnatifida was studied in batch and dynamicsystems. The kinetic uptake follows a pseudo second order rate equation indicating that the rate limitingstep is a chemical reaction. The equilibrium data are described by the Langmuir isotherm in monocomponent solutions. In binary solutions, the Jain and Snowyink model shows that most of the activesites are exclusively accessible to cadmium ions without competition with the zinc ions. The dynamicstudies show that the biosorbent has higher retention and affinity for Cd(II) than for Zn(II) in both monoand bi-component systems. SEM-EDX analysis indicates that the active sites are heterogeneouslydistributed on the cell wall surface. FT-IR spectrometry characterization shows that carboxylic groupsand chemical groups containing N and S contribute to Zn(II) and Cd(II) uptake by U. pinnatifida. Accordingto these results calcium-treated U. pinnatifida is a suitable adsorbent for Zn(II) and Cd(II) pollutants