eservoir, Taiwan. Before use, it wa

eservoir, Taiwan. Before use, it was washed with distilled water
to remove dirt and kept on filter paper to reduce water content.
The biomass was then sun-dried for 4 days, followed by oven drying
at 70 C for 24 h, and ground in a gate stone pistol mortar. The
biomass was then sieved to select particles between 150 and 250
mesh size for use.
Stocks of 1000 mg L1 metal solutions were prepared using
Pb(NO3)2, and Cu(NO3)23H2O (analytical grade) in deionized water.
Nitrate was chosen as the counter ion because of its low tendency
to form metal complexes. The solutions were then diluted to the
desired concentrations and analyzed