Sorption of Bisphenol A as Model for Sorption Ability of Organoclays

Abstract

The arrangement of bisphenol A molecules into organoclays and their interactions with the intercalated surfactant were studied. The organoclays were prepared via solid-state intercalation of four cationic surfactants, such as dodecyltrimethyl-, tetradecyltrimethyl-, hexadecyltrimethyl-, and didodecyldimethyl-ammonium, as bromide salts, at different loading levels into the interlayers of two natural clays. The natural clays, the prepared organoclays, and the spent organoclays were characterized by X-ray powder diffraction, infrared spectroscopy, and scanning electron microscopy. X-ray powder diffraction measurements showed successive interlayer expansions of the d001 basal spacing due to the intercalation of the cationic surfactants and the bisphenol A sorption. The increased d001 basal spacing of the organoclays after bisphenol A sorption indicates that the molecules are integrated between the alkyl chains of the surfactant in the organoclays interlayers. Infrared spectroscopy was employed to probe the intercalation of the cationic surfactants and the sorbed bisphenol A. New characteristic bands attributed to the bisphenol A phenol rings appear in the range 1518–1613 cm−1 on the infrared spectra of the spent organoclays, proving the presence of bisphenol A in the hydrophobic interlayers. Scanning electron microscopy of the organoclays before and after BPA sorption shows that their morphology becomes fluffy and that the presence of the organic molecules expands the clay structure.

Electrochemical Properties of Surfactants Modified Smectite Clays

“…The present study is devoted to the electrochemical characterization of organoclays modified carbon paste electrodes, based on three surfactants such as dodecyltrimethylammonium (n-C12H25(CH3)3NBr denoted (C12)), tetradecyltrimethylammonium (n-C14H25(CH3)3NBr denoted (C14)), and hexadecyltrimethylammonium (n-C16H33(CH3)3NBr denoted C16) intercalated into two natural smectite clays from Siétougou (denoted AH) and Diabari (denoted DI) samples collected in the Eastern part of Burkina Faso. The organoclays (C12-AH, C12-DI, C14-AH, C14-DI, C16-AH, and C16-DI) used in the present work have been successfully synthesized via solid-state intercalation and characterized by using XRPD, FT-IR, and SEM, as reported in our previous studies [15,16].…”