Isotherms
Data on adsorption equilibrium at 308 K are shown in Figure 6, together with curves adjusted via the Freundlich isotherm model. Clearly the Freundlich model fitted the data very satisfactorily, in full agreement with the findings of various researchers quoted previously.
The parameters of the Freundlich model were determined by nonlinear regressions of data at 308 K with the following results: 1 n 3n k 0.05kgp ms / kgr = − , n = 0.59 and r2 = 0.975.
In addition to the finite bath experiments, blank tests, i.e., without the resin, were carried out to check for phenol photodegradation and/or evaporation. After fourteen days, no measurable variation in phenol concentration was detected.