Nickel(II) Determination by Spectrophotometry Coupled with Preconcentration Technique in Water and Alloy Samples

摘要

A micro organism Agrobacterium tumifacient as an immobilized cell on a solid support was presented as a new biosorbent in a simple and sensitive spectrophotometry determination of Ni(II) in various samples using 4-hydroxy benzaldehyde-4-bromophenyl hydrazone as a color developing agent (lambda_(max) 497 nm) at pH 4.0 ± 0.2.Beer's law was obeyed over the range of 0.01-0.1 ug L~(-1).The molar absorptivity and Sandell's sensitivity were 1.285 x 10~5L mol~(-1)cm~((-1) and 0.007245 pg cm~(-2) respectively.Under these conditions,the preconcentration factor obtained was 82,and the detection limit achieved was 0.05 pg L~(-1).The detailed study of various interfering ions made the method more sensitive and selective.The recovery of Ni(II) from various samples range from 97.75 to 99.35%.The present method was successfully applied for the determination of Ni(II) in spiked,natural water and alloy samples.The proposed method was compared with reported methods in terms of Student's 't'-test and Variance ratio 'f'-test which indicates that there is no significant difference between proposed and literature method at 95% confidence level.