title: Electrokinetic and adsorption properties of sepiolite modified by 3-aminopropyltriethoxysilane.
abstract: Surface modification of clay minerals has become increasingly important for improving the practical applications of clays such as fillers and adsorbents. An investigation was carried out on the surface modification of sepiolite with aminopropylsilyl groups in 3-aminopropyltriethoxysilane (3-APT). The zeta potential of the modified sepiolite suspensions was measured as a function of initial electrolyte concentration and equilibrium pH using a Zeta Meter 3.0 for modified sepiolite. The utility of the 3-APT-modified sepiolite was investigated as an adsorbent for removal of various heavy metal ions such as Fe, Mn, Co, Zn, Cu, Cd and Ni from aqueous solutions. The effects of various factors on the adsorption, such as pH, ionic strength and temperature of the solution were studied. The results showed that the amount adsorbed increases with solution pH in the pH range of 1.5 and 7.0; indicated that the modified sepiolite adsorbed Fe and Mn ions more than other metal ions such as Co, Zn, Cu, Cd and Ni. It was found that the temperature had an important effect on metal ion adsorption by the modified sepiolite. The adsorption isotherm has been determined and data have been analyzed according to the Langmuir and Freundlich models.
authors.affiliation: Balikesir University, Faculty of Science and Literature, Department of Chemistry, 10145 Balikesir, Turkey.
authors.forename: Ozkan
authors.initials: O
authors.lastname: Demirbaş
authors.forename: Mahir
authors.initials: M
authors.lastname: Alkan
authors.forename: Mehmet
authors.initials: M
authors.lastname: Doğan
authors.forename: Yasemin
authors.initials: Y
authors.lastname: Turhan
authors.forename: Hilmi
authors.initials: H
authors.lastname: Namli
authors.forename: Pinar
authors.initials: P
authors.lastname: Turan
mesh_terms: D000327:Adsorption; D002627:Chemistry, Physical / Q000379:methods*; D004573:Electrolytes; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste; D007477:Ions; D007700:Kinetics; D017633:Magnesium Silicates / Q000737:chemistry*; D008670:Metals / Q000737:chemistry; D008956:Models, Chemical; D011437:Propylamines; D012821:Silanes / Q000737:chemistry*; D013499:Surface Properties; D013696:Temperature; D018508:Water Purification / Q000379:methods*
chemical_list: D004573:Electrolytes; D007220:Industrial Waste; D007477:Ions; D017633:Magnesium Silicates; D008670:Metals; D011437:Propylamines; D012821:Silanes; C001671:magnesium trisilicate; C477625:amino-propyl-triethoxysilane