Infrared Study of the Sorption of Phenol and p‐Nitrophenol by Montmorillonite

Abstract

Abstract The sorption of phenol and p ‐nitrophenol by montmorillonite saturated with different cations was studied by IR and X‐ray spectroscopy. Various associations between interlayer cations, water, and phenols were proven. Depending on the nature of the cation, phenol can act either as a proton donor or acceptor. The electrophylic NO 2 substituent of the ring increases the acidic strength of the phenol group: therefore, p ‐nitrophenol tends to behave mainly as a proton donor. The nitro‐group acts as an electron donor and, depending on the hydration status of the clay, either accepts protons from water coordinated to cations, or directly coordinates to the metallic cations.