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Rapid industrial scale production, coupled with unique material properties, under-pin rising concerns of nano-scale materials inadvertently impacting the health and func-tion of natural systems. Carbon based, nano-scale materials such as fullerenes and nanotubes in particular, have been widely proposed for a variety of applications. Fun-damentally understanding the behavior of these materials in natural matrixes is critical for accurate risk assessments and effective waste disposal management. Of particular interests are interactions with high-surface area, charged sub-surface fractions such as clay minerals and natural organic matter as they relate to the fate and transport proc-esses of said materials. To date, information regarding interactions between fullerenes and fullerene derivatives with clay minerals has been limited and focused on underivat-ized fullerenes in organic solvent and/or specific water soluble fullerene derivatives in-teracting with defined clay minerals. Research presented herein details specific interactions between C60 as an aggre-gate suspension (20-150 nm crystalline aggregates of underivatized fullerenes in water - termed nano-C60 ) and clay minerals; specifically, with a smectite (Ca-bentonite Cal-cigel, Bavaria Germany; Sudchemie AG), a kaolinite (KGa-1, Georgia; CMS source clay), and a synthetic layered double hydroxide (LDH Syntal HSA 696; Sudchemie AG). Batch and simple 1-D flow-through column interactions were analyzed via trans-mission electron microscopy, X-ray diffraction analyses and UV/Vis spectroscopy. Re-sults indicate that nano-C60 suspended in water does interact with clay minerals. The synthetic LDH, with a positive surface charge, had the greatest capacity to associate with the negatively charged nano-C60. Findings suggest that specific material interac-tions are primarily dominated by: - Available surface area; the more surface area available will result in higher associa-tion capacities. - Positively charged points on the mineral surface and/or edge in relation to the net negative surface charge of nano-C60 (as an electrostatic interaction). - Probable incorporation into mineral interlayers (smectite and LDH).  Fortner JD, Lyon DY, Sayes CM, Boyd AM, Falkner JC, Hotze EM, Alemany LB, Tao Yj, Guo W, Ausman KD, Colvin VL, Hughes JB. C-60 in water: Nanocrystal for-mation and microbial response. Environmental Science and Technology, 39 (2005) 4307
Authors:Fortner, John and Plötze, Michael and Solenthaler, Christian
Index Terms:ClayGroup; clay; c60; ldh; Fortner, John; Plotze, Michael; Solenthaler, Christian
Further Information:Date published: 2006