Structural-phase transformations in bentonite after acid treatment

Abstract

The methods of X-ray diffraction, Fourier transform infra-red spectroscopy (FTIR), X-ray microanalysis, electron microscopy, BET and cation exchange capacity (CEC) were used for investigation of the structural-phase transformations in bentonite under the influence of hydrochloric acid and temperature treatment (100-800°C). It is established that in HCl medium during temperature treatment, dehydration and dehydroxilation of montmorillonite occur. The presence of gypsum and barium chloride results in an intercalation of interlayer space of montmorillonite by Ca and Ba ions. Temperature treatment of intercalated montmorillonite leads to the formation of pores.