IONIC EXCHANGE ON NAX SYNTHETIC ZEOLITES IN THE PRESENCE OF SURFACTANTS

The paper presents the results of a detailed study upon the equilibrium and kinetics of the Ca2+ and Mg2+ ion exchange on NaX zeolite, in the presence of lineary alkylbenzene sodium sulphonate (LABS) and nonylphenylethoxylate (NF8). The experimental exchange isotherms showed that under the considered working conditions, the Ca2+ and Mg2+ equilibrium is not influenced by the neutral or anionic surfactants presence. In as far as the exchange rate is concerned, a decrease as compared to the witness sample - but a differentiated one - is observed for both cations. The Ca2+ ion exchange rate is diminished mom by the NF8, while the one of the Mg2+ ion is decreased more by the LABS. The surfactants presence in the system leads to a slight decrease of the exchange activation energy, this being an argument for the good washing behaviour of the detergents formulated with zeolites.