Adsorption of small organic pollutants from aqueous streams by aluminosilicate-based microporous materials

Location of MTBE and toluene in the channel system of the zeolite mordenite: Adsorption and host–guest interactions

“…Activated carbons have been the most commonly used adsorbents [2], but they present some disadvantages in that they are relatively expensive, difficult to regenerate, and their performance in removing pollutants is greatly reduced in the presence of natural organic matter, leading to competitive-adsorption effects [3]. Inorganic adsorbents with a high surface area and hydrophobic behavior represent a promising alternative to carbon adsorbents [1,[4][5][6][7][8].…”

“…The Silica/Alumina ratio is a fundamental parameter that defines zeolite polarity and influences the hydrophobicity or hydrophilicity of each zeolite. While the thermodynamics and kinetics of gas phase adsorption of organic molecules by zeolites has been widely investigated [9], studies of adsorption of organic molecules from aqueous solutions by zeolites are less numerous [5,6,[10][11][12][13][14][15]. Adsorption from aqueous solutions depends not only on the dimension of the pore systems, but also on the competition between the adsorbate and water, strictly linked to the hydrophobicity of the zeolite considered.…”

Static sorption of phenol and 4-nitrophenol onto composite geomaterials based on montmorillonite, activated carbon and cement

“…Shu et al [47] used aluminosilicate-based microporous materials (surfactantmodified Zr-pillared clays and zeolites) for substituted phenol sorption: they reported a sorption capacity of up to 0.75 mmol/g for phenol and 0.63 mmol/g for 4NP (on a high Si/Al ratio zeolite at pH 7). On a Mg/Al-mixed oxide derived from the corresponding layered double hydroxide, Chen et al [15] obtained a sorption capacity of 0.50 mmol/g for phenol and as high as 2.64 mmol/g for 4NP, although the final pH was 9-10 regardless of its initial value for the sorbate solution.…”

Removal of 2-Nitrophenol by Linde Type A (LTA) zeolites

“…These contaminants are generated from a number of industrial manufacturing processes such as pesticide, paint, solvent, pharmaceutical, wood preserving chemicals, and pulp industries (Pi et al, 2007). Specific adsorbents are used for the removal of phenols from aqueous solution (Abburi, 2003;Furuya et al, 1997;Dargaville et al, 1996;Shu et al, 1997;Ku and Lee, 2000;Dutta et al, 2001;Shen, 2002;Denizli et al, 2001).…”