Autor(es):
Ferraz, A. I.
; Tavares, M. T.
; Teixeira, J. A.
Data: 2000
Identificador Persistente: http://hdl.handle.net/1822/3691
Origem: RepositóriUM - Universidade do Minho
Descrição
To recover adsorbed metals from biosorbents, in order to recycle metal and reuse biomass in
several adsorption/desorption cycles, elution conditions need to be optimized. The present work
aimed to study the following elution parameters: eluant type and concentration (H2SO4, HNO3,
HCl, CH3COOH and Na2CO3 0.1, 0.5 and 1.0 M, and EDTA 0.01, 0.05 and 0.1 M); biosorbent
contact time with Cr (III) solution (15 min, 2 and 24 h), and S/L ratio (4 and 8 g/L).
Experimental data show a decrease in Cr recovery efficiency with increasing sorption time,
probably due to metal bioaccumulation. Concerning the S/L ratio, it was possible to observe, in
most essays, that best recoveries were achieved using biosorbent concentration of 8 g/L.
Comparing the eluants tested according to their metal recovery efficiencies, it can be concluded
that Na2CO3 is not a good eluant (maximum recovery of 21 %). All the others showed
equivalent behaviours, being necessary more assays to determine eluant treatment effect in Cr
uptake capacity in subsequent sorption cycles.