title: Amino-functionalized MCM-41 and MCM-48 for the removal of chromate and arsenate.
abstract: The aim of the present work was to investigate the efficiency of three amino-functionalized (hexadecylamine, dodecylamine, and dimethyldodecylamine) mesoporous silicas (MCM-41 and MCM-48) toward the adsorption of arsenate and chromate. Hexadecylamine-functionalized materials were characterized; BET surface areas, pore volumes, and sizes decreased with the functionalization, whereas XRD patterns show that the hexagonal structure of MCM-41 and the cubic structure of MCM-48 were not modified. The zeta potential decreases with pH and the highest arsenate and chromate removal was observed at the lowest pHs. Adsorption of chromium and arsenate was significantly enhanced after functionalization and amino-functionalized MCM-41 adsorb larger amounts of arsenate when compared to expanded MCM-48 materials. Chromate sorption capacities increased with the chain length and the larger capacities were obtained with hexadecylamine-functionalized mesoporous silicas. Mesoporous silicas modified by dimethyldodecylamine exhibited the higher arsenate sorption capacities.
authors.affiliation: Université des Sciences et TechniquesM. Boudiaf, Faculté des Sciences, Département de Chimie, Oran El M'Naouer, Algeria.
authors.forename: A
authors.initials: A
authors.lastname: Benhamou
authors.forename: J P
authors.initials: JP
authors.lastname: Basly
authors.forename: M
authors.initials: M
authors.lastname: Baudu
authors.forename: Z
authors.initials: Z
authors.lastname: Derriche
authors.forename: R
authors.initials: R
authors.lastname: Hamacha
mesh_terms: D000327:Adsorption; D000588:Amines / Q000737:chemistry*; D001149:Arsenates / Q000737:chemistry*; D002840:Chromates / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D012822:Silicon Dioxide / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification / Q000379:methods*
chemical_list: D000588:Amines; D001149:Arsenates; D002840:Chromates; C509968:MCM-41; D014874:Water Pollutants, Chemical; D012822:Silicon Dioxide