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Neste trabalho foi estudada a adsorção de Ag + sobre montmorilonita (MMT) do tipo Wyoming rica em Na + . Os dados de adsorção foram ajustados de acordo com várias isotermas comuns, mas os melhores parâmetros de regressão foram obtidos pelo modelo de Langmuir, indicando que Ag + foi adsorvido na superfície de MMT formando monocamadas. A adsorção de pequenas quantidades de Ag + promoveu o aumento da área superficial específica (SSA) de micro (r = 0.4-0.5 nm) a mesoporos (r = 1.5-3 nm). A intercalação de Ag + em MMT foi observada por difração de raios-X (XRD). Com o aumento da concentração de soluções de nitrato de prata, a quantidade de Ag + em MMT também aumentou e a estrutura em camadas gradualmente sofreu colapso e esfoliação. As amostras de MTT saturadas com Ag + foram tratadas com solução de boro hidreto de sódio para produzir Ag 0 . Foi estimado um tamanho médio de L 111 = 8.5(1) nm dos cristalitos de Ag 0 . As nanopartículas de prata metálica ficaram localizadas na superfície e nas bordas dos cristais de MMT.In this study Ag + adsorption on Na + -rich montmorillonite (MMT) type Wyoming was studied. Adsorption data were fitted with several common isotherms but the best regression parameters were obtained for Langmuir model. It indicates that Ag + was adsorbed on the MMT surface forming a monolayer. By adsorption of small amounts of Ag + enlargement of the specific surface area (SSA) of micro-(r = 0.4-0.5 nm) and mesopores (r = 1.5-3 nm) was found. Intercalation of Ag + into MMT was observed using X-ray diffraction (XRD). With increasing concentration of the silver nitrate solutions the content of Ag + in MMT increased and the layered MMT structure gradually collapsed and exfoliated. The MMT samples saturated with Ag + were treated with the sodium borohydride solutions to produce Ag 0 . The mean size of the Ag 0 crystallites of L 111 = 8.5(1) nm was estimated. The metal silver nanoparticles are assumed to be located at the layer surface and crystal edges of MMT.Keywords: adsorption, intercalation, silver, montmorillonite, nanoparticles IntroductionSilver is a noble metal with high electrical and thermal conductivity, chemical inertness to oxygen and many other gases and chemicals, photosensitivity to visible, X-ray and gamma-ray wavelengths in the electromagnetic spectrum, and also having catalytic and antibacterial properties. All these features have been widely used in many industrial applications. In the last few years, an effort of many basic research and application research laboratories has been focused on preparation of nanosize particles, which are known for their excellent physical and chemical properties. The two last mentioned papers describe silver reduction on silicates with layered structures (phyllosilicates). Their interlayer spacing serves as a nanoreactor, in which nanoparticles could form. The aim of this work was to investigate the adsorption of silver cations on montmorillonite, which seems to be capable of silver nanoparticles fabrication. Experimental ReagentsThe used chemicals were of ...