Sorption of Cyclohexylamine by Montmorillonites

Abstract

Infrared spectra indicate that protonation of cyclohexylamine sorbed by montmorillonite depends upon the interlayer cations and the origin of the lattice charge. No protonation occurs with Cs and very little with Na, but with all the other interlayer cations studied cyclohexylammonium ions are formed. Protonation occurs more readily if the lattice charge originates in the octahedral layer. Various associations are inferred between interlayer hydroxides, hydrated cations, ionic and molecular cyclohexylamine and water. The sorption of cyclohexylamine is compared with that of aniline and the validity of the concept “surface acidity” is questioned.