BIOSORPTION OF Pb2+, Cd2+, & Ni2+ FROM WATERS BY ...

5. pH adjustment: Various concentrations (0.1-1.0 M) of HNO3(aq) (Merck)
and NH3(aq) (Merck) solutions were used.
6. H2SO4 solution (5 %): Prepared by diluting 5.0 mL of concentrated H2SO4
(Merck, 96%) to 1000 mL with ultra-pure water.
7. Na-Silicate (6 %): Prepared by diluting the appropriate volumes of stock
Na-Silicate (Sigma-Aldrich) solution to 250.0 mL with ultra-pure water.
8. Agarose (2.0g/90.0mL): Prepared by dissolving 2.0 g of agarose (Sigma-
Aldrich) in 90.0 mL of ultra-pure water.
9. Triton X-100 (0.01 %): Prepared by diluting 1.0 mL of Triton X-100 to
100.0 mL with ultra-pure water.
10. Na-Citrate (0.1 M): Prepared by dissolving 2.941 g of Na-citrate tribasic
dihydrate (Sigma-Aldrich) and diluting to 100.0 mL with ultra-pure water.
11. HCI (0.1 M): Prepared by diluting 0.835 μL of concentrated HCI to 100.0
mL with ultra-pure water.
12. BaCI2 (0.2 M): Prepared by dissolving 1.221 g of BaCI2.2H2O (Riedel-de
Haën) and diluting to 25.0 mL with ultra-pure water.
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