2.1. Adsorbate
The copper nitrate hemipentahydrate, copper(II) acetate, copper(
II) chloride dihydrate, copper sulfate pentahydrate, lead(II) nitrate,
lead(II) acetate trihydrate and lead(II) chloride salts used
were of A.R. grade. Stock solutions containing 1000 mg/L of adsorbate
were prepared with distilled water and diluted as necessary.