Using capillary isotachophoresis for the study of intercalation of quaternary salts into montmorillonite

Intercalates of organics with montmorillonites (MMT) are perspective sorben ts for scavenging organic pollutants (chlorophenols, dioxines) from water e nvironment. Easily exchangeable interlayer cations in MMT can be replaced b y or ganoammonium or organophosphonium cations. A simple and East isotachop horetic method for determination of tetramethyl (TMA(+)). trimethyl(phenyl) -(TMPA(+)), and tetrabutylammonium (TBA(+)) cations in water solution based on MMT intercalation was proposed and verified. The tested method yielded reproducible and correct data. The achieved detection limits and sensitivit y match the requirements of the batch equilibrium technique used for adsorp tion experiments. Sorption curves showed the following sorption maxima for the cations per g of Na-MMT: 0.98 mmol TMA(+), 0.97 mmol TMPA(+), and 0.84 mmol TBA(+). These values are in a very good agreement with elemental analy ses of saturated TMA-MMT, TMPA-MMT and TBA-MMT.