Effect of time.
Measurements of metal ion uptake using batch method were conducted by placing 0.25g of the prepared chitosan in a series of stopper conical flasks containing 50 ml of calcium and magnisium metal ion solutions at pH 3.
The contents of the flasks were agitated on a shaker at 150 rpm and 30 C for 4 h. samples were taken at time intervals for the analysis of residual metal concentration in solution.