Rearrangement of cationic surfactants in magadiite

Abstract

Partly loaded magadiite samples have been prepared from a synthetic sodium magadiite, 0.9 Na₂O · 13.9 SiO₂ · 9.3 H₂O, by a two-step intercalation process using n-cetylpyridinium (CP) chloride as a model surfactant. Usually, partly loading with long-chain organic cations yields a non-uniform distribution of the surfactant molecules in the interlamellar space of the layered silicates. The resulting samples contain fully expanded crystals or zones within the crystals besides unreacted crystals or domains. After equilibration in water the partly loaded samples transform into products with a uniform expansion of all interlayer spaces due to rearrangement of the CP cations within and between the interlayer spaces.