Crystalline layered sodium kenyaite was exchanged to proton kenyaite when reacted with hydrochloric acid solution, providing a new surface with available silanol groups that are able to couple with N-3-trimethoxysilylpropylethylenediamine silylating agent, after prior expansion of the basal distance with the polar organic solvent dimethyl sulfoxide. The resulting organofunctionalized nanomaterial (2N-Ken) was characterized by elemental analysis, infrared spectroscopy, X-ray diffraction, carbon and silicon nuclear magnetic resonances in the solid state, surface analysis, porosity, thermogravimetry, and electron scanning microscopy. The quantity of silylating agent incorporated into the nanospace, calculated from the nitrogen elemental analysis, was determined as 0.48 mmol g(-1), after expanding of the acidic precursor basal distance from 1.62 to 1.99 nm. The presence of a covalent silicon-carbon bond of the organosilyl moiety on the inorganic layered structure was confirmed through nuclear magnetic resonance. This new nanomaterial has the ability to extract the Sumifix Brilliant Orange 3R textile dye from aqueous solution, using a batchwise process. The effects of stirring time, adsorbent dosage, and pH on the adsorption capacity demonstrated that 4 h is enough to reach equilibrium at 298+/-1 K under pH 4.0. Based on error function values (F(error)) the data were best fitted to fractional-order and chemisorption kinetic models when compared to pseudo-first-order and pseudo-second-order kinetic models. The equilibrium data were better fitted to the Sips isotherm model.

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Synthesized crystalline sodium lamellar kenyaite exchanges the original cation on the surface to yield silanol groups when exposed to hydrochloric acid solution. The silanol groups successfully favour the formation of covalent bonds with the silylating agents 3-aminopropyltriethoxysilane, N-propyldiethylenetrimethoxysilane and bis[3-(triethoxysilyl)propyl]tetrasulfide, after expanding the interlayer distance with polar organic solvents such as dimethyl sulfoxide (DMSO) and N,N-dimethylformamide (DMF). These new organofunctionalized nanomaterials were characterized by elemental analysis, infrared spectroscopy, X-ray diffraction, carbon and silicon nuclear magnetic resonance in the solid state, surface analysis, porosity, thermogravimetry, electronic scanning and transmission electron microscopies. The amounts of sililyating agents incorporated into the nanospace were 0.60 ¡ 0.02, 0.90 ¡ 0.04 and 0.96 ¡ 0.01 mmol g 21 , by expanding the interlayer distance of 1633 pm for the original polysilicate to 1933, 1847 and 1828 pm for the sequence of anchored nanocompounds. Nuclear magnetic resonance for 13 C and 29 Si nuclei confirmed the covalent attachment of the organosilyl groups inside the inorganic layered structures, as shown by carbon chemical shifts of the pendant organic chains, with distinguishable 3 Q and 4 Q species, followed by 2 T and 3 T species that correspond to the carbon to silicon bond originating from the precursor silylating agents covalently incorporated in the acidic kenyaite structure. These three new synthesized nanomaterials have the ability to remove divalent cations from aqueous solution. The adsorption isotherms were adjusted using a modified Langmuir equation, whose values enable calculation of the equilibrium constants and negative Gibbs free energies. The favourable values corroborate with the cation/basic centre interaction at the solid/liquid interface in a spontaneous process for these three new nanomaterials.

The CO 2 production by shift reaction and the deactivation process are the drawbacks of the One-Step DME Synthesis. Therefore, this contribution discusses possible deactivation modes taking into account the catalytic performance and the characterization of spent catalysts using XRD, TG and FTIR techniques. For this purpose a physical mixture that contains a commercial methanol catalyst and ZSM-5 was employed. It can be suggested that one of the main modes of catalyst deactivation is the hydrocarbon formation by MTG reactions. Changes in the interaction between Cu 0 and ZnO should also be considered. The results show that both of them are affected by H 2 /CO ratio.

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