TITLE:
Spectrophotometric Complexation Studies of Some Transition and Heavy Metals with a New Pyridine Derivative Ligand and Application of It for Solid Phase Extraction of Ultratrace Copper and Determination by Flame Atomic Absorption Spectrometry
AUTHORS:
Mahmood Payehghadr, Kobra Shahbala, Homa Shafikhani
KEYWORDS:
Copper; SPE; C18; Oyridine; FAAS; Spectrophotometry; Formation Constant
JOURNAL NAME:
American Journal of Analytical Chemistry,
Vol.4 No.1,
January
9,
2013
ABSTRACT:
A new pyridine derivative ligand, (E)-(Pyridine-2-ylmethylidene) ({2-(E)-(Pyridine-2-ylmethylidene) amino] ethyl} has
been synthesized and kf value of it’s complexes with Cu2+,
Ni2+, Cd2+, Zn2+, Co2+, Hg2+ and Ag+ has been determined spectrophometrically. The stability of the
complexes to vary in acetonitrile solvent was in the order of Cu2+ >
Ni2+ > Cd2+ > Zn2+ > Co2+ >
Hg2+ > Ag+, thus because this ligand have good selectivity
to copper ion, a simple, reliable and rapid method for preconcentration and determination
of the ultratrace amount of copper using octadecyl silica membrane disk modified
by this ligand, and determination by flame atomic absorption has been presented.
Various parameters including pH of aqueous solution, flow rates, the amount of ligand and the type of stripping
reagent were optimized. Under optimum experimental conditions, the breakthrough
volume is greater than 2000 ml with an enrichment factor of more than 400 and 0.054 μg×L?1 detection limit. The capacity of the membrane disks modified
by 6 mg of the ligand has been found to be330.17 gof copper. The effects of various cationic interferences on the percent recovery
of copper ion were studied. The method has been successfully applied for the determination
of copper ion in different water samples.