Anion selectivity of organobentonites

Effect of surfactant molecular structure on perchlorate removal by various organo-montmorillonites

“…More poorly hydrated head groups require lower free energy to displace the hydration shell and bind to the target anions with lower hydration energy (Wolff, 1998;Xiong et al, 2007). In the present work, the influence of the surfactant structure to modify Mt on the removal of perchlorate by modified Mt was examined, because of the potential harmfulness, high solubility and persistence of ClO (Haggety and Bowman, 1994;Bors et al, 1999;Behnsen and Riebe, 2008;Xi et al, 2010) and using the obtained organoclays to remove different inorganic anions (Atia, 2008). Although several research groups comparatively studied the influence of surfactant structure (number and length of alkyl chain) on surfactant configuration and distribution in organoclays (Xi et al, 2007;Zhu et al, 2012), the further application and significant discussion in inorganic anion adsorption were not addressed.…”

“…The hydrated inorganic cations (e.g., Na + ) can be introduced in the interlayer space and readily replaced by cationic surfactants. Functional head groups in the cationic surfactant are responsible for ion exchange with pollutant anions (Behnsen and Riebe, 2008;Fang et al, 2013). The adsorption capacity greatly depends on the entrapped amount of counter ion-accompanying surfactant.…”

Rhenium(VII) and technetium(VII) separation from aqueous solutions using a polyethylenimine–epichlorohydrin resin

“…The highest Re-removal efficiency among the investigated modified natural sorbents was shown by hexadecyl-pyridiniummodified bentonite (2.3 mmol/g) [13], the polyethylenimine-modified lignin sludge exchanger (1.3 mmol/g) [31] and the amine-modified corn stalk (0.9 mmol/g) [32]. Among the investigated resins, the 4-amino-1,2,4-trazole resin (1.9 mmol/g) [23] and the anion-exchange resin D318 (1.9 mmol/g) [22] showed high Re-sorption capacity.…”

“…A number of raw and modified natural [9][10][11][12][13][14][15][16] as well as synthetic materials [17][18][19][20][21][22][23][24][25][26][27][28][29] have already been investigated as technetium and rhenium sorbents and extractants from aqueous solutions. Biomaterials and modified biomaterials were also studied for the removal of Re(VII) from waters [30][31][32].…”

Organo-Bentonit Üretimi ve Organo-Bentonitlerin Kirlilik Giderimi Çalışmalarında Kullanımı

“…Bu çalışmalarda sıcaklık uygulanması, organik YAM'nin bentonit süspansiyonuna eklenmesi sırasında gerçekleştirilmiştir [35,55,63,68,69]. Organik madde eklenirken ve daha sonra devam eden karıştırma esnasında 50-60 [39,67,70] veya mikrodalga fırın [55,70] kullanılarak veya dondurularak [60,71] kurutulur, öğütülür ve böylece kullanıma hazır hale getirilir [55,57,72].…”