Intercalating cationic surfactants in Koppies bentonite

Abstract

Single and double chain cationic surfactants were intercalated into Koppies bentonite. The state of the chains in the interlayers was probed using XRD, FTIR spectroscopy and thermogravimetric analysis (TG). The degree of intercalation was determined by TG and exceeded the CEC equivalent value by 30–40%. The degradation onset temperature of about 200◦C was independent of the number and length of alkyl chain substituents. The XRD d-spacing was consistent with monolayer interdigitated surfactant intercalation for the C12 and C14 single chain surfactants and with bilayer intercalation of the double chain surfactants. FTIR analysis revealed disordered alkyl chain conformations.