* Resin treatment—XAD-4 Amberlite, supplied by
Rohm and Haas of Gessate (MI), is a styrenedivinylbenzene
polymer, designed for organic compound
removal (for example, for organochlorine
compounds, herbicides and insecticides) from wastewaters.
The main characteristics of XAD-4 were:
surface area X700m2/g; granulometry=0.3–
1.20 mm; density=620 g/L. In contrast, Ambersorb
563 is an ionic exchange resin of styrene-divinylbenzene
sulphonate polymer with a high macro-porosity
and a moderate surface area. Different Ambersorb
types are produced with a wide range of polarity; the
563-type is one of the most hydrophobic. The main
characteristics of Ambersorb were: surface area=
550m2/g; granulometry=0.25–0.71 mm; microand
macro-porosity=0.23 mL/g; meso-porosity=
0.14 mL/g; density=530 g/L. The lake water
treatment (20L of sample) consisted of a filtration
through one glass column (25mm of diameter and
30 cm of height), contact time 10 min, filled with a
bed volume of 80mL for XAD-4 or a bed volume of
94mL for Ambersorb.