Montmorillonite organic complex

Harrison, R. (1982). A Study of Some Montmorillonite-Organic Complexes. Ph.D. dissertation, University of Birmingham. 

Byrne, P.J.S., 1954. Some observations on montmorillonite organic complexes. In A. Swineford and N. Plummer (Editors), Proceedings Second National Conference Clays and Clay Minerals. Natl. Acad. Sci.—Natl. Res. Counc., Washington, D.C., Publ. No. 327, pp. 241—253. 

Middeldorp PJM, De Wolf J, Zehnder AJB, Schraa G (1997) Enrichment and properties of a 1,2,4-trichlorobenzene-dechlorinating methanogenic microbial consortium. Appl Environ Microbiol 63 1225-1229 Miller ME, Alexander M (1991) Kinetics of bacterial degradation of benzylamine in a montmorillonite suspension. Environ Sci Technol 25 240-245 Montville R, Schaffner DW (2003) Inoculum size influences bacterial cross contamination between surfaces. Appl Environ Microbiol 69 7188-7193 Mortland, MM (1970) Clay-organic complexes and interactions. Advances in Agronomy 22 75-117... 

In addition to stabilizing organic products by reaction with metal-exchanged clays, as indicated above, aluminosilicate minerals may enable the preparation of metal organic complexes that cannot be formed in solution. Thus a complex of Cu(II) with rubeanic acid (dithiooxamide) could be prepared by soaking Cu montmorillonite in an acetone solution of rubeanic acid (93). The intercalated complex was monomeric, aligned with Its molecular plane parallel to the interlamellar surfaces, and had a metal ligand ratio of 1 2 despite the tetradentate nature of the rubeanic acid. 

Figure 5.3. Effects of various organic complexing ligands on the sorption of Cu by montmorillonite. (Modified from McBride, 1991.)...

BKG Theng. Organic complexes of montmorillonite. PhD dissertation. University of Adelaida, Australia. 1964. 

GREAVES M.P. and WILSON M.J. 1973. Effects of soil micro-organisms on montmorillonite-adenine complexes. Soil Biology and Biochemistry,... 

The most obvious mineral to examine is montmorillonite, which is a substance that shows great variability in composition. With this mineral, of course, mixed-layer structures are readily formed, as with the hydrates and organic complexes, if it is treated in a suitable way (see Section F on organic complexes). However, some results suggest that natural mont-morillonites may consist of an interleaving of layers of different composition and that these differences may be developed by suitable treatments. 

The catalytic application of clays is related closely to their swelling properties. Appropriate swelling enables the reactant to enter the interlamellar region. The ion exchange is usually performed in aquatic media because the swelling of clays in organic solvents, and thus the expansion of the interlayer space, is limited and it makes it difficult for a bulky metal complex to penetrate between the layers. Nonaqueous intercalation of montmorillonite with a water-sensitive multinuclear manganese complex was achieved, however, with the use of nitromethane as solvent.139 The complex cation is intercalated parallel to the sheets. 

When organic cations (e.g., cationic tensides) are employed, clay organo-complexes are formed, which can be used in organic solvents. A Pd-hexadecy-lammonium montmorillonite catalyst was prepared by the reduction of Pd(OAc)2 by ethanol in the interlamellar space. At small ethanol concentrations in toluene, selective interlamellar sorption of ethanol was established consequently, the reduction also occurred only in the interlamellar space.160 The catalyst was used for the hydrogenation of alkenes.161... 

Two types of complex are formed on reaction of benzene with Cu montmorillonite. In the Type 1 species the benzene retains Its aromaticity and is considered to be edge bonded to the Cu(II), whereas in the Type 2 complex there is an absence of aromaticity (85,86). ESR spectra of the Type 2 complex consist of a narrow peak close to the free spin g-value and this result can be explained in terras of electron donation from the organic molecule to the Cu(II), to produce a complex of Cu(I) and an organic radical cation. Similar types of reaction occur with other aromatic molecules. However with phenol and alkyl-substituted benzenes only Type 1 complexes were observed (87), although both types of complex were seen on the adsorption of arene molecules on to Cu(II) montmorillonites (88) and anisole and some related aromatic ethers on to Cu(II) hectorite... 

Interactions between adsorbed metal ions and complex organic molecules have been observed in other systems. For example, IR results Indicated that coraplexation occurred between sulfolane (C4 H8S02) and either Cu or NI montmorillonites, with the result that... 

Counterion extraction Due to the relative slowness of back extraction based on the methods above, the back-extraction of proteins encapsulated in AOT reverse micelles was evaluated by adding a counterionic surfactant, either TOMAC or DTAB, to the reverse micelles [33]. This novel backward transfer method gave higher backward extraction yields compared to the conventional method. The back-extraction process with TOMAC was found to be 100 times faster than back-extraction with the conventional method, and as much as three times faster than forward extraction. The 1 1 complexes of AOT and TOMAC in the solvent phase could be efficiently removed using adsorption onto montmorillonite so that the organic solvent could be reused. 

Brindley, G. W., and Moll, W. F., Jr. (1965). Clay-organic studies. IX. Complexes of natural and synthetic Ca-montmorillonites with fatty acids. Am. Min. 50,1355-1370. 

Inskeep, W. P. and J. Baham. 1983. Competitive complexation of Cdll and Cull by water soluble organic ligands and Na-montmorillonite, Soil Sci. Soc. Am. J. 47 1109. 

In the present work we examine the microporosity of a TSLS complex formed from synthetic imogolite and natural montmorillonite. Nitrogen adsorption and desorption isotherms are reported and analyzed in terms of microporous volume and surface area. Also, the adsorption isotherm for an organic adsorbate, m-xylene, is reported. Preliminary FTIR results for the chemisorption of pyridine and catalytic studies of the dealkylation of cumene suggest that TSLS complexes are promising microporous acids for shape selective chemical conversions. 

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