Lad. Gomes et al., Determination of metal ions in fuel ethanol after preconcentration on 5-amino-1,3,4-thiadiazole-2-thiol modified silica gel, J BRAZ CHEM, 9(5), 1998, pp. 494-498
This work describes the synthesis and characterization of 5-amino-1,3,4-thi
adiazole-2-thiol modified silica gel (SiATT), and the results of a study of
the adsorption and preconcentration (in batch, and in flow using a column
technique) of Cd(II), Co(II), Cu(II), Fe(III), Ni(II), Pb(II) and Zn(II) in
ethanol medium. The adsorption capacities for each metal ion were (in mmol
g(-1)): Cd(II) = 0.11, Co(II) = 0.10, Cu(II) = 0.20, Fe(III) = 0.20, NL(II
) = 0.16, Pb(II) = 0.08 and Zn(II) = 0.12. The results obtained in the flow
experiments, showed a recovery of ca. 100% of the metal ions adsorbed in a
column packed with 2 g of SiATT, using 5 mL of 2.0 mol L-1 HCl solution as
eluent. The sorption-desorption of the metal ions made possible the develo
pment of a preconcentration method and quantification by Flame AAS of metal
ions at trace level in fuel ethanol.