Adsorption of a cationic gemini surfactant from aqueous solution onto aluminosilicate powders of the MCM-41 type: effect of pore size and co-adsorption of phenol

Effect of alcohol addition to the aqueous phase on the thermal effects of micellization of cationic benzyldimethyldodecylammonium bromide and its adsorption onto porous and nonporous silicas

“…Microcalorimetry was preferentially chosen for the solubilization and adsolubilization experiments. This technique is very attractive for analysis of such mixed systems, since it offers the opportunity of comparing the various interactions involved in surfactant aggregation both in the aqueous phase and at the solid-solution interface [21][22][23][24][25][26]. All experiments at the solid-solution interface were carried out at the free pH of the aqueous phase, either in the presence or in the absence of background electrolyte (NaBr).…”

Calorimetry at the Solid–Liquid Interface

“…With a small amount of phenol added to the aquous phase, the displacement phenomenon is more exothermic in this region: the related portion of the enthalpy [114]. The dpl h di f f enthalpy is plotted against the adsorption coverage of the solid surface by the surfactant cations curve can be viewed as shifted towards more negative values by a constant value in comparison with the curve corresponding to the system without phenol.…”

“…6.32 Molar enthalpies of micellisation, mic h, for selected quaternary ammonium surfactants in pure water and in the presence of phenol molecules in the aqueous phase at 298 K [88,114,115]. The overall phenol (PhOH) content (in mmol kg −1 ) is reported on the X-axis.…”

Adsolubilization of dihydroxybenzenes into CTAB layers on silica particles

“…This might be because of the structure difference between hydroquinone and catechol. It is suggested that the interaction between dihydroxybenzenes and CTAB molecules is as follows [12]: their π -electron clouds interact with the electric field produced by the cationic head groups of the surfactant. For hydroquinone, the dihydroxy groups are in the opposite site, so it can interact with surfactant molecule by electrostatic force without any adverse factors as shown in Fig.…”

“…However, there is no apparent rule between the tail length of surfactant and the adsolubilization amount [7]. The category of the solid surfaces including alumina [8,11,12], mica [4], laponite clay [9] and silica [3][4][5]13,14] have been widely investigated, too. Another important factor is the condition of the bulk solution which could influence the form of the surfactant aggregation on surface [5,6].…”