Química Nova | |
Ion-selective electrode for potentiometric determination of aluminium(III) in fluoride medium | |
Piccin, Evandro1  Universidade Federal de São Carlos, São Carlos1  Fatibello-Filho, Orlando1  Universidade de São Paulo, São Carlos1  Ramos, Luiz Antonio1  | |
关键词: aluminium(III) determination; ion-selective electrode; potentiometry.; | |
DOI : 10.1590/S0100-40422004000600012 | |
学科分类:化学(综合) | |
来源: Sociedade Brasileira de Quimica | |
【 摘 要 】
The construction and analytical evaluation of a coated graphite Al(III) ion-selective electrode, based on the ionic pair formed between the Al(F)n3-n anion and tricaprylylmethylammonium cation (Aliquat 336S) incorporated on a poly(vinylchloride) (PVC) matrix membrane are described. A thin membrane film of this ionic pair and dibutylphthalate (DBPh) in PVC was deposited directly on a cylindric graphite rod (2 cm length x 0.5 cm diameter) attached to the end of a glass tube using epoxy resin. The membrane solution was prepared by dissolving 40% (m/m) of PVC in 10 mL of tetrahydrofuran following addition of 45% (m/m) of DBPh and 15% (m/m) of the ionic pair. The effect of membrane composition, fluoride concentration, and several concomitants as potential interferences on the electrode response were investigated. The aluminium(III) ion-selective electrode showed a linear response ranging from 1.4 x 10-4 to 1.0 x 10-2 mol L-1, a detection limit of 4.0 x 10-5 mol L-1, a slope of -54.3±0.2mV dec-1 and a lifetime of more than 1 year (over 3000 determinations for each membrane). The slope indicates that the ion-selective electrode responds preferentially to the Al(F)4- species. Application of this electrode for the aluminium(III) determination in stomach anti-acid samples is reported.
【 授权许可】
Unknown
【 预 览 】
Files | Size | Format | View |
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RO201912050593205ZK.pdf | 174KB | download |