To study the effect of the initial metal ion concentration on
biosorption capacity of MOSB, solutions of Co(II), Cu(II) and Zn(II)
in the concentration range 1–14 mg L−1 were prepared and 0.5 g of
biomass was added to 60 mL of solution (single, binary and ternary)
in 100 mL bottles. The bottles were left shaking on an orbital shaker
for 24 h, centrifuged and filtered prior to analysis as described in
Section 2.3