The sorbent to solution ratio was selected to achieve a
10–90% extent of a compound removal from the solution. The
applicability of the upper limit of solute removal was controlled
mostly by analytical accuracy and sensitivity allowing measuring
relatively low solute concentrations remaining in solution. The
final reproducibility of sorption data was indicative whether the
removal extent had an impact on accuracy of sorption isotherms.
Initial aqueous concentrations of simazine and diuron varied
between 0.5–4.5 and 2–30 mg L1, respectively thus being below
the solubility limits which are 6.2 and 42 mg L1, respectively