The modified bentonite performance in adsorption process of organic and inorganic contaminants from aqueous phase

Abstract

Bentonite from Dilinh (Lamdong province, Vietnam) was used for pillaring and organofunctionalization process in the present study. The pillaring agent was obtained through controlled hydrolysis of AlCl3.6H 2O/NaOH. Aluminium pillared clay (Al-PILC) was prepared by contacting of Aluminium pillaring agent and Na-montmorillonite (MONT-Na) aqueous suspension with different ratios. Then, Al-PICL was organofunctionalized with cetyltrimethylammonium bromide (CTAB). The obtained materials were characterized by XRD, IR, DTA-TGA, SEM, BET and 27Al-MAS-NMR methods. On the 27Al-MAS-NMR spectrography of Keggin ions and Al-PICL tetragonal Aluminium AlO4 and hexagonal Aluminiums AlO6 appears at 66.14 and 0 ppm, respectively. The increase in d001 of basal spacing was as expected since the pillaring causes an expansion in the interlayer distance. SEM is used to probe the change in morphological features of MONT-Na and Al-PILC. The surface morphology of MONT-Na is different from that of Al-PILC. The MONT-Na appears as corn flake like crystals, revealing its extremely fine platy structure. After pillaring, clay has become more porous. This porous appearance probably occurs due to the pillars formed between the interfaces of clay sheets as a result of pillaring and the reduction in certain amorphous phase originally associated with the MONT-Na. IR spectrography improved the interaction between Al-PICL and CTAB. Their adsorption capacity was investigated with methyl orange, methylene blue and copper ion from aqueous solution controlled temperature 298 ± 0.20 K. The obtained results show that Al-PICL-CTAB is best to remove organic contaminants from aqueous solution and also good to treat the water contaminated copper ion before re-use. © 2011 The Surface Science Society of Japan.