Interfacial behavior of concentrated HCl solution and water clustered at a surface of nanosilica in weakly polar solvents media

• Published in: Colloids and surfaces. A, Physicochemical and engineering aspects Vol. 390; no. 1; pp. 48 - 55
• Main Authors: Turov, V.V., Gun’ko, V.M., Turova, A.A., Morozova, L.P., Voronin, E.F.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 20.10.2011; Elsevier
• Subjects: 1H NMR; bulk density; carbon tetrachloride; Chemistry; Clustering; Colloidal state and disperse state; colloids; DCl/HCl solution; Exact sciences and technology; Fumed silica; gastric juice; General and physical chemistry; HCl adsorption; Hydrochloric acid; Interfacial phenomena; Media; Nanomaterials; nanoparticles; Nanostructure; nuclear magnetic resonance spectroscopy; Physical and chemical studies. Granulometry. Electrokinetic phenomena; Porous materials; silica; Silicon dioxide; solvents; Surface chemistry; Surface physical chemistry; Voids; Water adsorption; Interfacial phenomena; Water adsorption; 1H NMR; DCl/HCl solution; Fumed silica; HCl adsorption; Water; Binary compound; Confinement; Nanoparticle; NMR spectrometry; Density; Porous material; Silica; Mechanism; Powder; Hydrochloric acid; Adsorbent; H NMR; Low temperature; Concentrated solution; Polar solvent; Adsorption; Pore; Aggregate; Differentiation; Interface
• ISSN: 0927-7757; 1873-4359
• DOI: 10.1016/j.colsurfa.2011.08.053

[Display omitted] ► Effects of mechanochemical activation of nanosilica on textural and adsorption characteristics. ► Confined space effects on the characteristics of bound water. ► Effects of silica on interaction of HCl with water. ► Chemical shifts of the proton resonance as a measure of associativity of interfacial water and aqueous solution of HCl. Low-temperature 1H NMR spectroscopy was used to study water and concentrated hydrochloric acid solution clustered at a surface of silica A-300 initial and mechanochemically activated (MCA) with the bulk density ρ b = 0.045 and 0.394 g/cm 3, respectively. Hydrochloric acid solution in contact with silica powder placed in nonpolar (CCl 4) or weakly polar (CDCl 3) media forms clusters of two types (with different content of HCl and water) in interparticle voids in aggregates of silica nanoparticles. This differentiation is stronger in the system with MCA silica because of enhanced confinement effects in narrower pores (voids) between adjacent nonporous nanoparticles. Obtained results are of importance for deeper insight into the mechanism of the influence of nanosilica used as an oral sorbent on the gastric juice properties.