Adsorption behavior of poly(vinylpyrrolidone) toward Fuller's earth suspensions

The adsorption of poly(vinylpyrrolidone) (PVP) onto Fuller's earth surface was studied at fixed pH (4.2) and room temperature (27 +/- 0.2 degreesC). T he kinetics of the adsorption process was monitored and various adsorption and kinetic parameters such as the adsorption coefficient, the rate constan ts for adsorption and desorption, the diffusion constant, and the penetrati on constant were evaluated. The effects of various experimental factors suc h as the pH and the presence of inorganic and organic anions or aliphatic a lcohols were also studied on the adsorbed amounts of PVP. The role of tempe rature was also investigated and various thermodynamic parameters such as t he standard Gibb's free energy, enthalpy, and entropy were also evaluated. (C) 2000 John Wiley & Sons, Inc.