An aluminous montmorillonite has been synthesized at hydrothermal conditions (623 K, 120 MPa) and compared to the natural Na-exchanged Wyoming montmorillonite (Na-SWy2). The synthetic product is characterized by a high cation exchange capacity (83 meq/100g) and ethylene glycol specific surface area (764 m 2 /g) similar to Na-SWy2 but with a higher purity with one crystalline phase. Compacted sm...

-The crystalline and osmotic swelling of N~, Cs-, Mgand Ca-montmorillonite has been measured in dimethyl sulphoxide and in formamide, N-methyl formamide, dimethyl formamide, N-methyl acetamide and dimethyl acetamide. These liquids have similar dipole moments but their relative permittivities vary appreciably from values less than water to values greater than water. Na montmorillonite exhibits o...

The spatial organisation of swelling clay platelets in a suspension depends on the chemical composition of the equilibration solution. Individual clay platelets can be well dispersed, with surfaces entirely in contact with the external solution, or be stacked in tactoids, where part of the surfaces forms parallel alignments embedding interlayer water and cations. External and interlayer surface...

Intercalation products based on ionic exchange reaction between cationic dye methylene blue and Na-montmorillonite were prepared. Montmorillonite particles intercalated with methylene blue were characterized using X-ray diffraction, infrared spectroscopy, elemental and thermo-gravimetric analysis. The results showed that intercalation of dye molecules within the interlayer spaces of montmorillo...

Silica sol, i.e., colloidal SiO2, may be used as a low-pH injection grout for very fine fractures in the construction of deep geological repositories for radioactive waste in Sweden and in Finland. If the bentonite barrier encounters SiO2-colloid particles under conditions favorable for aggregation, there is concern that it will modify the bentonite barrier at the bentonite/bedrock interface. I...

The thermal emission of alkali metal ions from Al30-pillared montmorillonite in comparison with its natural form was studied by mass spectrometry in the temperature range 770-930 K. The measurements were carried out on a magnetic mass spectrometer MI-1201. For natural montmorillonite, the densities of the emission currents (j) decrease in the mass spectrum in the following sequence (T = 805 K, ...

Molecular dynamics simulations, conventional and metadynamics, were performed to determine the interaction of model protein Gb1 over kaolinite (001), Na(+)-montmorillonite (001), Ca(2+)-montmorillonite (001), goethite (100), and Na(+)-birnessite (001) mineral surfaces. Gb1, a small (56 residue) protein with a well-characterized solution-state nuclear magnetic resonance (NMR) structure and havin...

A simple and efficient method for the synthesis of quinolines and polycyclic quinolines using Li+ modified nanoporous Na+-montmorillonite is described. This new nanocatalyst proceeds via Friedlander annulation under solvent-free conditions. It describes our observations about a trend of catalytic activity of Lithium cation in nanoporous Na+-montmorillonite. In this study, several types of 1,3-d...