Determination of europium by using the chemical oscillating system of Ce(IV)-KBrO3-acetone-oxalic acid-H2SO4

AbstractA sensitive and convenient method for the determination of trace europium ions using an oscillating chemical reaction involving Ce(IV) - KBrO3 - acetone - oxalic acid - H2SO4 was proposed. The results indicated that the changes in oscillating period (T) was linearly proportional to the negative logarithmic concentration of Eu3+ (-log C) in the range of 1.41 × 10−8 ˜ 1.41 × 10−4 mol L−1 (r = 0.9982) with a detection limit of 1.04 × 10−9 mol L−1. The recoveries were limited to the range of 99.5% to 100.8%. Under the same conditions, other rare earth ions did not interfere with the determination of Eu3+. In addition, a perturbation mechanism was also discussed briefly.

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Determination of sulfanilamide based on the Mn(II)-catalyzed oscillating chemical reaction

Open Chemistry ◽

10.2478/s11532-007-0007-y ◽

2007 ◽

Vol 5 (2) ◽

pp. 581-589 ◽

Cited By ~ 1

Author(s):

Jinzhang Gao ◽

Dongyu Lv ◽

Wu Yang ◽

Xiaoxia Wei ◽

Jie Qu ◽

...

Keyword(s):

Linear Relationship ◽

Lower Limit ◽

Chemical Reaction ◽

Limit Of Detection ◽

Optimum Conditions ◽

Oscillating Period ◽

Sensitive Method ◽

Oscillating Chemical Reaction

AbstractA convenient and sensitive method for determination of sulfanilamide (SNA) was described based on the Mn(II)-catalyzed oscillating chemical reaction. Under optimum conditions, a linear relationship existed between the changes of oscillating period or amplitude and the negative of logarithm of SNA concentration in the range of 4.27 × 10−8 mol ·L−1 ∼ 7.41 × 10−6 mol ·L−1 (RSD, 0.85%) and 9.33 × 10−8 mol ·L−1 ∼ 3.02 × 10−6 mol ·L−1 (RSD, 1.08%), respectively. The lower limit of detection was found to be 2.69 × 10−8 mol ·L−1 and 6.03 × 10−8 mol ·L−1, respectively.

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The fluorimetric determination of cerium and terbium

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19890616 ◽

1989 ◽

Vol 54 (3) ◽

pp. 616-621 ◽

Cited By ~ 3

Author(s):

Záviš Holzbecher

Keyword(s):

Rare Earth ◽

Detection Limit ◽

Rare Earth Elements ◽

Fluorimetric Determination ◽

Fluorescence Maximum ◽

Relative Standard ◽

And Shifts ◽

Hcl Medium ◽

Fold Excess

It has been found that phosphoric acid decreases the first excitation maximum of Ce(III) at 256 nm, increases the second excitation maximum at 297 nm and shifts the fluorescence maximum from 350 to 346 nm. Under optimum conditions, with λexc = 297 nm and λem = 346 nm, Ce(III) can be determined fluorimetrically with a detection limit of 1.2 ng ml-1 in 12M-H3PO4 medium. No interference was observed from a 20-200 fold excess of HCl, H2SO4, Na, K, NH4+, Al and the rare earth elements. HNO3 interferes and Ce(IV) and Fe(III) interfere strongly. It follows from the stereofluorograms of Ce and Tb that the spectra of the two elements are practically independent. The detection limit for Tb(III) in 0.02-2.5M-H2SO4 medium for λexc = 222 nm and λem = 494 nm is 33 ng ml-1. No interference was observed from a 5-20 fold excess of Al3+ and the other rare earth elements. The determination is slightly less sensitive in H3PO4 or HCl medium. The relative standard deviation of the measurement for 10 ng ml-1 Ce(III) or 50 ng ml-1 Tb(III) is about 3%.

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