Radioisotope study of fructose adsorption at the alumina/electrolyte interface

The mechanism, kinetic and static studies of fructose adsorption at the alumina/electrolyte interface using radiolabeled 14C-fructose were conducted. Pseudo 2nd order model of adsorption kinetics was found to fit best to adsorption as a function of time. The fructose adsorption was found to decrease with increasing pH of the solution. Considering the changes in concentration of surface groups at the alumina/electrolyte interface, the hydrogen bonding is the most probable mechanism of interaction of fructose with the surface. This is confirmed by calorimetric titration experiments because the measured heat of adsorption was 10.8 kJ/mol. For the system studied the coverage of surface by fructose was several times smaller than the monolayer.