Surface and interface physicochemical aspects of intercalated organo-bentonite

Enriching composite hydrophilic polyurethane foams with PAC to enhance adsorption of phenol from aqueous solutions

“…5a and b). A similar mechanism was observed by Fan et al, [44]; (3) electro-static attraction between HPU foam surfaces and negatively charged PAC surfaces [45], where the holding capacity of the composite foams was influenced by impregnating negatively charged powder biomass, clay and PAC [46][47][48] in the HPU foams. These negatively charged particle additives cause a decrease of the electrostatic attraction potential for PAC particles from the aqueous suspension, leading to a decrease in PAC-enrichment capacity of the foams (Fig.…”

Structural characterization of hexadecyltrimethylammonium-smectite composites and their potentiometric electrode applications

“…It can be seen from Fig. 3 that organosmectites have two or three DTG peaks in the temperature range of 250-450 • C. The appearance of more than one DTG peaks points out that there were different locations of the HDTMA cations in the smectite structure [33,45]. Furthermore, the dehydroxylation temperature of organosmectites shifts to lower temperature with the higher HDTMA loadings compared to the raw smectite which may be explained by the easier loss of the hydroxyl units from the organosmectite [18,24,34].…”

“…The surface areas and pore volumes decreased with the increasing amount of the surfactants illustrating that intercalated surfactants of larger molecular size were compact packed in the interlayer space. This compact packing causes more serious pore blocking that inhibits the passage of nitrogen [12,33,72]. On the other hand, the disappearance of microporous surface areas of all organoclays can be explained by blocking of the micropore openings by the surfactants embedded into the interlamellar space.…”

“…The penetration of cationic surfactants not only changes the surface properties from hydrophilic to hydrophobic but also may change the charge of the raw clay layer from negative to positive if the excess of organic cations available [30][31][32][33].…”

Preparation and Characterization of Montmorillonite-Cetyl Trimethylammonium Bromide

“…There are monovalent and bivalent cations such as Na + , Ca 2+ and Mg 2+ among the octahedral and the tetrahedral layers. This arrangement causes the formation of interior space and charge interlayer [1][2][3]. It also provides two different sections within the layer of negatively charged clay which is insoluble in water and the cations electrostatically attached to the lining of the micelles.…”