title: Solid Phase Extraction and Preconcentration of Trace Gallium, Indium, and Thallium Using New Modified Amino Silica.
abstract: Amino silica gel functionalized with 2-hydroxy-5 -(2-hydroxybenzylideneamino)benzoic acid was synthesized, characterized and used as adsorbent for the removal of Ga3+, In3+and Tl3+from aqueous solution prior to their determination by flame atomic absorption spectrometry. Experimental parameters that affect the separation process were investigated in both batch and column modes. The maximum adsorption capacities of the sorbent are 61.7 mg g-1, 81.3 mg g-1and 133.0 mg g-1for Ga3+, In3+and Tl3+, respectively. The preconcentration factor is 200 and the limits of detection of Ga3+, In3+and Tl3+are 4.10 μg L-1, 1.55 μg L-1and 1.21 μg L-1, respectively. Interference by Al3+can be masked by the addition of F-; and that of Fe3+by its reduction to Fe2+using 10% ascorbic acid. The method was successfully applied for the determination of these ions in water, sediments and liquid crystal display samples.
authors.affiliation: 1 Chemistry Department, Beni-Suef University, Egypt.
authors.forename: Mohamed M
authors.initials: MM
authors.lastname: Hassanien
authors.affiliation: 2 Urology and Nephrology Center, Mansoura University, Egypt.
authors.forename: Wael I
authors.initials: WI
authors.lastname: Mortada
authors.affiliation: 3 Chemistry Department, Mansoura University, Egypt.
authors.forename: Ibrahim M
authors.initials: IM
authors.lastname: Kenawy
authors.affiliation: 3 Chemistry Department, Mansoura University, Egypt.
authors.forename: Heba
authors.initials: H
authors.lastname: El-Daly
keywords: Solid phase extraction; flame atomic absorption spectrometry; gallium; indium; modified amino silica; thallium