Abstract
Some nanoparticulated sorbents, known in the specialty literature and practical use as organoclays were prepared, based on native sodium smectite modified with some quaternary ammonium cations – hexadecyltrimethylammonium (HDTMA), N-cetylpyridinium (NCPy), dimethyldioctadecylammonium (DDA) and alkylbenzyldimethylammonium (ABDMA) – through a ion exchange reaction. The products were characterized by means of sorption isotherms over a range of 0 ÷ 250% satisfaction degree of the cation exchange capacity (CEC), by desorption tests and by TG analysis. Adsorptive properties were assessed by means of sorption isotherms towards several nonionic surfactants (NISs): two nonylphenol ethoxylates: NPEO8 and NPEO12 and one fatty alcohol ethoxylate with 10 ethoxy groups, EUSAPON OD. The HDTMA and NCPy-organoclays were effective adsorbents for both nonylphenol and fatty alcohol ethoxylates, with high sorption limits. The DDA-organoclay showed significantly lower sorption limits.The ABDMA proved to be inactive towards the nonionic surfactants.