A multilayer adsorption of perfluorohexanesulfonic and perfluorobutanesulfonic acids on bio-based polyurethane/chitosan foam: Advanced interpretation of the adsorption mechanism

This work presents an application of a multilayer model derived from statistical physics to the adsorption experimental data of two industrial pollutants, namely perfluorohexanesulfonic (PFHxS) and Perfluorobutanesulfonic (PFBS) acids on a bio–based polyurethane /chitosan(PU/CH) adsorbent foam, at T = 298–328 K and pH 4. This model shows that the number of PFHxS and PFBS layers formed on adsorbent surface increases from 1.61 to 3.80, and from 1.56 to 2.26 respectively by increasing the temperature.This means that the adsorbate molecules are arranged on a variable number of layers.