Uptake of metal ions by nonliving biomass derived from marine organisms‐effect of ph and chemical treatments

Abstract

The nature of metal binding by four strains of nonliving marine biomass, the green algae Cladophora profitera and Ulva lactuca, the brown alga Padina pavonica, and the sea plant Zostera marina were studied. Specifically, the effect of pH on the degree of binding of Cu(II), Pb(II), Zn(II), Cd(II), Cr(III), Ni(II), Co(II), Mn(II), Al(III), Au(III), Ag(I), and TI(I) was investigated. For most metals studied binding was very strongly pH dependent, with maximum binding observed at pH 5–6; only Au(III) showed a negative effect of pH on binding. A pH dependence on the binding of several metals was observed for U. lactuca at both 10 and 100‐ppm levels. Very pronounced interspecies differences in metal binding capacity and specificity were observed. Acidic or basic treatments generally increased the degree of metal binding. Multi‐treatment with both acid and base significantly increased subsequent Pb(II), Cu(II), Zn(II), and Cd(II) binding by U. lactuca. Triton X‐100 detergent treatment led to a slight increase in binding of Pb(II), Cu(II), Zn(II), and Cd(II) by U. lactuca.

Key words:

• Uptake
• metal ions
• biomass
• marine
• pH
• chemical treatments