2. Reagents and equipments
All of the chemical reagents were analytical grade and without further
purification. The solid CuSO4∙5H2O and Pb(NO3)2 (Fisher Scientific
Company) would be used to generate 1000 mg/L standard stock of lead
solution and copper solution that would be diluted to different concentrations
for experiments. HNO3 and NaOH solutions with the same
concentration of 0.1 mol/L were respectively prepared to adjust pH
value in the batch experiment. Meanwhile, a Perkin Elmer AAnalyst