scholarly journals Visible Spectrophotometric Determination of Tantalum in Soil, Sediment, Minerals, and Alloys

2001 ◽  
Vol 84 (2) ◽  
pp. 399-406 ◽  
Author(s):  
Khageshwar Singh Patel ◽  
Aditya Shukla ◽  
Neeta Agarwal ◽  
Peter Hoffmann

Abstract A new, sensitive, and selective method is described for the spectrophotometric determination of Ta(V). The method is based on the extraction of the Ta(V)–F−–CV+ complex (CV+ = crystal violet cation) with a benzene solution of imidoyl derivatives (ID), i.e., N,N′-diphenylbenzamidine (DPBA), N-hydroxy- N,N′-diphenylbenzamidine, and N-(2,5-dimethyl)phenyl-p-tolylimidoylphenylhydrazine, from sulfuric acid solution; DPBA was selected for detailed study. The molar absorptivities of the Ta(V)–F−–CV+–ID complexes in the benzene solution were in the range of (1.00–1.65) × 105 L/mol·cm at 600 nm. The limit of detection was 7 ng Ta/mL (which had an absorbance greater than that of the blank + 3 standard deviations). The optimization of the analytical variables, the composition of the complex, and the effect of diverse ions in the determination of Ta are discussed. The present method was applied to the determination of Ta in environmental samples, i.e., soil, sediment, minerals, and alloys.

1993 ◽  
Vol 76 (3) ◽  
pp. 604-608 ◽  
Author(s):  
Sumon Chakravarty ◽  
Manas Kanti Deb ◽  
Rajendra Kumar Mishra

Abstract A simple, sensitive, and selective extractive spectrophotometric method for the determination of cadmium in trace quantities with N1-hydroxy-N1,N2- diphenylbenzamidine (HDPBA) and 4-(2-pyridylazo) naphthol (PAN) is described. The method is based on the extraction of cadmium with HDPBA into chloroform at pH 9.0 ± 0.2 and simultaneous spectrophotometric determination wiith PAN. The binary Cd(ll)-HDPBA complex extracted into chloroform has a molar absorptivity of 1.96 x 104L/ mol/cm at λmax 400 nm. The sensitivity of the yellow Cd(ll)-HDPBA complex was increased remarkably by the addition of PAN to the binary complex. With 6 different hydroxyamidines tested, the red-orange complex in chloroform exhibited maximum absorbance at 530-550 nm, with molar absorptivity values of 3.2-5.6 x 104L/mol/cm. The method adheres to Beer’s law up to 1.5 μg cadmium/mL organic phase. The detection limit of the method is 0.02 μg Cd/mL. Investigations of the effect of foreign ions revealed that the present method is free from matrix interference of most of the common ions (e.g., Fe(lll), Ni(ll), Cu(ll), Mn(ll), V(V), Co(ll), Al(lll), Cu(ll), Mg(ll), and Mo(VI)). The relative standard deviation for 10 repetitive analyses of the metal was 1.4%. The validity of the method was tested successfully with various environmental samples.


2020 ◽  
Vol 85 (1) ◽  
pp. 89-96 ◽  
Author(s):  
Denys Snigur ◽  
Alexander Chebotarev ◽  
Vitaliy Dubovyi ◽  
Dmytro Barbalat ◽  
Anastasiia Klochkova

The novel cloud point extraction procedure for preconcentration of copper(II) was discovered. A simple chemical method for initiating the cloud point extraction (CPE) has been proposed. The formation of surfactant rich phase in a system containing a nonionic surfactant Triton X-100, copper(II), 6,7-dihydroxy-4-methyl-2-phenylbenzopyrilium chloride (DHMPhB) and ammonium benzoate is observed immediately upon the sulfuric acid addition into solution. Under the optimal conditions (absorption band maximum was 540 nm, concentration 1.5?10-4 mol dm-3 of DHMPhB, 1.0 vol.% of Triton X-100, 2.0 cm3 of 0.75 mol dm-3 ammonium benzoate, and 1.0 cm3 of 0.5 mol dm-3 sulfuric acid solution for obtaining benzoic?benzoate buffer solution with pH 4.5 and initiation immediate surfactant rich phase formation) the calibration plot for spectrophotometric determination of copper(II) was linear in the range of copper(II) concentration 0.02?0.95 ?g cm?3. The limit of detection was calculated 0.006 ?g cm?3. The water samples were analyzed according to a suggested procedure with satisfactory results.


2006 ◽  
Vol 129 (1-3) ◽  
pp. 271-276 ◽  
Author(s):  
K. Suresh Kumar ◽  
K. Suvardhan ◽  
D. Rekha ◽  
K. Kiran ◽  
G. Chalapathi Rao ◽  
...  

2010 ◽  
Vol 9 (2) ◽  
pp. 254-260
Author(s):  
Choirul Amri ◽  
Dwi Siswanta ◽  
Mudasir Mudasir

A study of extraction-spectrophotometric method for the determination of trace nitrite as 4-(4-nitrobenzenazo)-1-aminonaphthalene complex using n-amylalcohol and chloroform as organic solvents has been done. Results of the study showed that extraction-spectrophotometric determination of nitrite using n-amylalcohol or chloroform was very sensitive and had low limit of detection. Extraction-spectrophotometric method of nitrite using n-amylalcohol gave range of linear concentration 0.000-0.054 mg/L NO2--N, detection limit of 2.09x10-4 mg/L NO2--N, and sensitivity of 34.514 ± 0.398 absorbance unit per mg/L of NO2--N. Meanwhile, extraction-spectrophotometric of nitrite using chloroform had range of linear concentration of 0.000-0.100 mg/L NO2--N, detection limit of 8.99x10-4 mg/L NO2--N, and sensitivity of 18.353 ± 0.456 absorbance unit per mg/L NO2--N.   Keywords: Nitrite Trace, 4-(4-Nitrobenzenazo)-1-Aminonaphthalene, Extraction-Spectrophotometry


2021 ◽  
Vol 9 (2) ◽  
pp. 64-71
Author(s):  
Mykola Blazheyevskiy ◽  
◽  
Valeriy Moroz ◽  
Olena Mozgova ◽  
◽  
...  

The oxidative derivatization method using potassium hydrogenperoxomonosulfate for the indirect spectrophotometric determination of Fluphenazine hydrochloride is presented. Potassium hydrogenperoxomonosulfate is introduced as a derivatizing agent for Fluphenazine hydrochloride, yielding the sulfoxide. This reaction product was successfully used for the spectrophotometric determination of the Fluphenazine hydrochloride. The UV spectroscopic detection of the sulfoxide proved to be a more robust and sensitive method. The elaborated method allowed the determination of Fluphenazine hydrochloride in the concentration range of 0.2-30 µg mL-1. The molar absorptivity at 349 nm is 5.6×103 (dm3cm-1mol-1). The limit of quantification, LOQ (10S) is 0.24 µg/mL. A new spectrophotometric technique was developed and the possibility of quantitative determination of Fluphenazine hydrochloride in tablets 5.0 mg was demonstrated. The present method is precise, accurate and excipients did not interfere. RSD for Fluphenazine Hydrochloride 5.0 mg tablets was 1.37 %.


2008 ◽  
Vol 152 (3) ◽  
pp. 903-909 ◽  
Author(s):  
S. Adinarayana Reddy ◽  
K. Janardhan Reddy ◽  
S. Lakshminaraya ◽  
D. Lalitha Priya ◽  
Y. Subba Rao ◽  
...  

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