Organosilicas and organo-clay minerals as sorbents for toluene

• Published in: Applied clay science Vol. 52; no. 1; pp. 184 - 189
• Main Authors: Seliem, Moaaz K., Komarneni, Sridhar, Cho, Yunchul, Lim, Taesook, Shahien, M.G., Khalil, A.A., Abd El-Gaid, I.M.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 01.04.2011; Elsevier
• Subjects: Bromides; Contaminants; Earth sciences; Earth, ocean, space; Exact sciences and technology; MCM-41; MCM-48; Mineralogy; Minerals; Nanocomposites; Nanomaterials; Nanostructure; Organo-clay minerals; Silicates; Surfactants; Toluene; MCM-48; MCM-41; Toluene; Organo-clay minerals; adsorption; bromides; X-ray diffraction; ground water; mica; exhibits; halides; sorption; smectite; montmorillonite; aquifers; materials; temperature; sheet silicates; silicates; clay minerals; soils; hydrothermal conditions; toluene
• ISSN: 0169-1317; 1872-9053
• DOI: 10.1016/j.clay.2011.02.024

This study investigated the adsorption of toluene as a non-ionic organic contaminant by organosilicas and organo-clay minerals. Different organic surfactants were used to prepare a variety of MCM-41 molecular sieves at room temperature while cetyltrimethylammonium (CTMA) bromide was used to synthesize MCM-48 mesoporous material under hydrothermal conditions. Organo-clay minerals were synthesized under hydrothermal conditions using synthetic low-charge Na-fluorophlogopite micas with CTMA bromide as organic surfactant. All synthetic organosilicas and organo-clay minerals, the latter including those procured from two commercial sources were characterized by powder X-ray diffraction (XRD) and their toluene sorption properties were investigated. Among organosilicas, MCM-48 exhibited the highest distribution coefficient ( K d ) value of toluene (95 ± 9 L/kg). An organo-clay mineral, Nanomer® PGW montmorillonite modified with CTMA bromide (Nanomer® 1.28E) showed the maximum K d value (345 ± 22 L/kg) for toluene among all the studied organosilicas and organo-clay minerals. The organo-clay mineral nanocomposites were found to be superior to MCM-41 and MCM-48 organosilicas tested here and the former could find applications in remediating organic contaminants such as toluene from soil and groundwater.