Sepiolite clay

Competitive adsorption on sepiolite clay of a monovalent dye (e.g., methyl green or methyl blue) and of the divalent organo-cationic herbicides diquat and paraquat was studied by Rytwo et al. (2002). To evaluate a possible competitive adsorption between the two organic compounds, separate aqueous solutions of each cation were used and adsorption isotherms were obtained. Fig. 8.27 shows the amount of diquat, paraquat, and methyl green adsorbed on sepiolite as a function of total added divalent cation. It may be observed that, when the added amounts were lower than the cation exchange capacity of the sepiolite (O.Mmol kg ), aU cations were completely adsorbed. 

H, 2H and 29Si solid state NMR study of guest acetone molecules occupying the zeolitic channels of partially dehydrated sepiolite clay... 

Sepiolite clay (<100 mesh) was heated in air at 120°C in order to remove the zeolitic and surface bound water molecules. The partially dehydrated clay mineral was subsequently exposed to acetone vapor at room temperature for a period of four days. H and 29Si CP MAS-NMR experiments revealed that the acetone molecules penetrated into the microporous channels of the sepiolite structure. Broad line 2H NMR studies using acetone-d6 revealed that, in addition to fast methyl group rotations, the guest acetone-d6 molecules were also undergoing 2-fold re-orientations about the carbonyl bond. The presence of acetone-d6 molecules adsorbed on the exterior surfaces of the sepiolite crystals was also detected at room temperature. 

H, 2H and 29Si Solid State NMR Study of Guest Acetone Molecules Occupying the 551 Zeolitic Channels of Partially Dehydrated Sepiolite Clay M.R. Weir, G.A. Facey and C. Detellier... 

Abdul-Latif, N. and Weaver, C.E., 1969. Kinetics of acid-dissolution of palygorskite (attapulgite) and sepiolite. Clays Clay Miner., 17 169-178. 

Preisinger, A., 1959. An X-ray study of the structure of sepiolite. Clays Clay Miner., Proc. 6th Conf., pp. 61-67. 

Visible light-induced cleavage of water has been reported for a mixed colloidal clay system consisting of a mixture of sepiolite clay-Ru02-Ru(bpy)3 + colloid (for O2 production) and Al,cEui (OH)3-Pt colloid (for H2 production) [165]. A turnover number of 20 with respect to the sensitizer, Ru(bpy)3 +, was observed. It was reported that the gas (H2 + O2) evolution displayed a damped oscillatory behavior. Photo-oxidation of water by tran5-diaqabis-(2,2 -bipyridine)ruthenium(2- -) adsorbed on the surface of hectorite clay has also been reported [166]. 

The effect on the modulus and yield stress of the scCCh processed PP nanocomposites was studied for the addition of MWNTs and sepiolite clays (Ma et al., 2007 and 2010). The results were comp>ared with traditional melt compounded nanocomposites. 

Bhattacharyya, A Sreekumar, T. liu, T. Kumar, S. Ericson, L. Hauge, H. Smalley, R. (2003) Crystallization and Orientation Studies in Polypropylene/Single Wall Carbon Nanotube Composite. Polym. Vol.44, N0.8, pp.2373-2377, ISSN 0032-3861 Bilotti, E. Fischer, H. Peijs, T. (2008) Polymer nanocomposites based on needle-like sepiolite clays Effect of functionalized polymers on the dispersion of nanofiller, crystallinity, and mechanical properties, f. Appl. Polym. Sci. Vol.107, No.2 pp.lll6-1123, ISSN 0021-8995... 

Dehydration of sepiolite clays under temperature scan of 20K/min in inert atmosphere. The dashed lines represent the temperature window at which clays are typically subjected to during polyolefin composites preparation (extrusion and compression/injection moulding) [11]. 

TGA mass loss curves and their derivative of PP nanocomposites, based on sepiolite clay, multi-wall carbon nanotube (CNT) or their combination, in oxidative (left) and inert (right) atmosphere [65]. 

Bilotti, E. 2009. Polymer/sepiolite clay nanocomposites. PhD thesis. Queen Maiy University of London, London, U.K. 

Bilotti, E., Fischer, H. R., and Peijs, T. 2008. Polymer nanocomposites based on needle-like sepiolite clays Effect of functionalized polymers on the dispersion of nanofiller, crystallinity, and mechanical properties. Journal of Applied Polymer Science 107 1116-1123. 

Chivrac, E., Pollet, E., Schmutz, M., Averous, L. Starch nano-biocomposites based on needlelike sepiolite clays. Carbohydr. Polym. 80, 145-153 (2010)... 

X-ray diffraction analysis (XRD) is one of the microstructural analysis methods used for the identification of aystaUinity of polymers, recognition of crystalline phases (polymorphism), and orientation of polymers. Olivato et al. [64] prepared starch/ polyester nanobiocomposites based on sepiolite clay, and from wide-angle XRD they showed no significant alteration of the crystalline structures of PBAT and starch induced by the sepiohte clay. Scaffaro et al. [155] added OMM to HDPE/PA-6 blends using a co-rotating TSE and characterized by SEM, TEM, and XRD analyses. They... 

Focusing on reinforced polysaccharide films, positively charged chitosan (a linear polysaccharide mainly extracted from shrimp and other crustacean shells) was assembled with sepiolite clay, giving rise to self-supported bionanocomposite films with interesting structural and functional properties. In this study, Darder and co-authors [113] revealed that the association of sepiolite and chitosan resulted in a threefold improvement in the mechanical properties as compared with unmodified... 

AhMchs JL, Serna C, Serratosa JM (1975) Structural hydroxyls in sepiolites. Clays Clay Miner 23 119 124... 

Santaren J, Sanz J, Ruiz-Hitzky E (1990) Structural fluorine in sepiolite. Clay Miner 38 63-68... 

Inagaki S, Fukushima Y, Doi H, Kamigaito O (1990) Pore-size disMbution and adsorption selectivity of sepiolite. Clay Miner 25 99-105... 

Li ZH, Wilhns CA, Kniola K (2003) Removal of animiic contaminants using surfactant-modified palygorskite and sepiolite. Clays Clay Miner 51 445-451... 

Verge P, Fouquet T, Barrere C, Toniazzo V, Ruch D, Bomfim JAS (2013) Organomodi-fication of sepiolite clay using bio-sourced surfactants compatibilization and dispersion into epoxy thermosets for properties enhancement. Compos Sci Technol 79 126-132... 

Chivrac F, Pollet E, Schmutz M, Averous L (2010) Starch nano-biocomposites based on needle-Uke sepiolite clays. Carbohydr Polym 80 145-153... 

Sandi G, Winans R. E., Seifert S. and Carrado K. A., In situ SAXS studies of the structural changes of sepiolite clay and sepiolite-carbon composites with temperature. Chemistry of Materials 14(2) (2002), 739-742. 

Sepiolite Clay-AEM (Preliminary Partial Grade Listing). 160... 

The term pipe clay is frequently treated as synonymous with kaolin q.v.). However, tobacco pipes are manufactured from the sepiolite clay mineral q.v.) known as meerschaum (sea-foam). This hardened clay is derived from lake deposits, the best known of which are in Eskisehir, Turkey. 

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