Preparation and simultaneous sorption of CTMAB-HTCC bentonite towards aniline and Cr (VI)

Cetyltrimethyl ammonium bromide–N-2-hydroxypropyl trimethyl ammonium chloride chitosan bentonite was prepared by modifying bentonite with cetyltrimethyl ammonium bromide and N-2-hydroxypropyl trimethyl ammonium chloride chitosan for the purpose of simultaneous sorption of aniline and Cr (VI) from aqueous solution. The optimal preparation conditions of cetyltrimethyl ammonium bromide–N-2-hydroxypropyl trimethyl ammonium chloride chitosan bentonite were listed as follows. For bentonite (5 g), the modifying reagents were 1.0 g cetyltrimethyl ammonium bromide and 1.0 g N-2-hydroxypropyl trimethyl ammonium chloride chitosan, respectively. The reaction was carried out for 2 h at 60°C. Adsorption experiments with single aniline and Cr (VI) solutions showed that the adsorption of aniline was caused by aniline partitioning between water and the organic-matter phase formed by conglomeration of the alkyl chains of cetyltrimethyl ammonium bromide, while the one of Cr (VI) was controlled by the electrostatic interactions and chelation between Cr (VI) and N-2-hydroxypropyl trimethyl ammonium chloride chitosan. No competition was noticed between aniline and Cr (VI) under the experimental conditions.