Spectrophotometric determination of peroxymonosulfate anions via oxidative decolorization of dyes induced by cobalt

2016 ◽  
Vol 8 (5) ◽  
pp. 973-978 ◽  
Author(s):  
J. Q. Zhang ◽  
J. Ma ◽  
J. Zou ◽  
H. Z. Chi ◽  
Y. Song

Dyes can be decolorized by the activation of peroxymonosulfate (PMS) in the presence of cobalt, and four good linear correlations between the depletion of dyes at their maximum absorption wavelengths and the concentration of PMS are demonstrated under the optimum conditions.

2010 ◽  
Vol 2 (3) ◽  
pp. 161-166 ◽  
Author(s):  
Mudasir Mudasir ◽  
Mugiyanti Mugiyanti ◽  
Ngatidjo Hadipranoto

An analytical method for the spectrophotometric determination of some phenolic compounds, i.e.: pyrocathecol and pyrogallol based on their redox reaction with iron(III)-phenanthroline complex has been developed. These two compounds, in appropriate conditions, reduce iron(III)-phenanthroline complex to yield very stable and color-intense complex of iron(II)-phenanthroline, [Fe(phen)2]2+, whose concentration is equivalent to the amount of pyrocathecol or pyrogallol in the solution, and is easily detected by spectrophotometric method. Some parameters influencing the sensitivity of the determination were optimized. These included maximum absorption wavelength, pH of the solution, time and temperature of heatingand reagent to analyte minimum mole-ratio. Using the optimum conditions obtained, the analytical performance of the method was examined and the developed method was then applied to analyzed pyrocathecol and pyrogallol contents in several river water of Yogyakarta, Indonesia. Result of the study showed that the optimum conditions for the determination of pyrocathecol are as follows: maximum absorption wavelength (lmax) at 510 nm, pH of the solution = 4, heating time = 120 min, heating temperature = 70 0C and the minimum mole ratio of reagent to analyte is 8. On the other hand, the optimum conditions for the determination of pyrogallol are as follows: maximum absorption wavelength (lmax) at 510 nm, pH of the solution = 5, heating time = 90 min, heating temperature = 90 0C and the minimum mole ratio of reagent to analyte is 7. At the corresponding conditions of analysis, calibration curves for pyrocathecol and pyrogallol are linear in the range concentration of 0.00 - 0.16 ppm and 0.00 - 0.24 ppm, respectively. The correlation coefficients for both compounds were found to be higher than 0.998 and the detection limits went down below 0.07 ppm. It has been demonstrated that the developed method can be applied for the determination of pyrocathecol and pyrogallol contents in natural samples.   Keywords: Spectrophotometry, phenolic compounds, 1,10-phenanthroline, redox reaction


2013 ◽  
Vol 726-731 ◽  
pp. 1453-1456
Author(s):  
Ai Hui Liang ◽  
Jing Peng ◽  
Yuan Li ◽  
Ling Ling Ye ◽  
Gui Qing Wen

In the presence of NaOH, glucose hydrolyze and polymerize to generate yellow carbon nanoparticles that had an absorption peak at 336 nm. Under the selected conditions, result showed the concentration of glucose have a good linear relationship between absorbance value and glucose concentration in the range of 0.0005-0.060 mol/L. This method has been used for the assay of glucose injection sample, with simplicity, rapidity, and accuracy.


1988 ◽  
Vol 66 (3) ◽  
pp. 401-405 ◽  
Author(s):  
Lumír Sommer ◽  
Eva Šamlotová

2-(5-Bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP) is a suitable reagent for the spectrophotometric determination of uranium but results are easily influenced by the reaction conditions as well as various common ions and masking agents. Optimum conditions, which must be carefully maintained, are 30% (v/v) dimethylformamide, 0.1% triton X-100, ≥ 8 × 10−5 M 5-Br-PADAP, 8 × 10−2 M triethanolamine, 7 × 10−3 M sodium fluoride, 10−2 M 5-sulphosalicylic acid, and 579 nm. Sodium sulphate (10−2 M) and CDTA (5.7 × 10−3 M) may serve as additional masking agents. A previous separation of uranium by extraction with 0.1 M tri-n-octylamine in benzene from 4 M HCl and re-extraction of 0.3 M HCl is recommended for analysis of natural water samples.


1979 ◽  
Vol 44 (2) ◽  
pp. 374-392 ◽  
Author(s):  
Ellena Russeva ◽  
Vlastimil Kubáň ◽  
Lumír Sommer

The composition, molar absorption, coefficients, equilibrium constants and stability constants for the MLH, ML, M(LH)2 and ML2 complexes have been determined graphically using slope-intercept transformations and numerically from the absorbance-pH curves and from the absorbance dependence on the component concentration, using the PRCEK III and SPEKTFOT programs, or from the continuous variation plots using the JOBCON program. The optimum conditions were found for a spectrophotometric determination of ferric ions with TAR and PAR reagents in pure solutions. The basic parameters of the analytical curves were evaluated using the STAT program.


2009 ◽  
Vol 6 (4) ◽  
pp. 1267-1273
Author(s):  
Reyhaneh Rahnama Kozani ◽  
Ferydoun Ashrafi ◽  
Masuod Khalilnezhad ◽  
Mohammad Reza Jamali

A simple, sensitive, rapid and reliable method has been developed for spectrophotometric determination of iodide based on its inhibition effect on the redox reaction between bromate and hydrochloric acid. The decolorization of methyl orange by the reaction products was used to monitor the reaction spectrophotometrically at 525 nm. The variables affecting the rate of the reaction were investigated. Under the optimum conditions, the limit of detection is 1.5 × 10-7mol L-1and calibration range is 2.0 × 10-6–1.3 × 10-4mol L-1of iodide. The linearity range of the calibration graph is depends on bromate concentration. The relative standard deviation of ten-replication determination of 8.2 × 10-5mol L-1iodide was 1.4%. The proposed method was applied to the determination of iodide in natural water samples with satisfactory results.


2013 ◽  
Vol 838-841 ◽  
pp. 2034-2039
Author(s):  
E Zhang ◽  
Xiao Ming Chen ◽  
Mei Liu ◽  
Xiao Ling Liu ◽  
Yan Xu ◽  
...  

The spectrophotometric determination has been widely used by virtue of low investment, simple equipment, convenient operation and high accuracy. The study discussed the application of picramazochrom spectrophotometry to measure Co (II) in the bacterial culture media including LB, NA and TGY medium. The parameters of chromogenic reaction containing absorption wavelength, buffer solution volume, chromogenic reagent volume and developing time were optimized. Under optimum conditions, the calibration graph was linear in the concentration range of 0~1.5mg/L (r2=0.9991) for Co (II). The LB, NA and TGY medium prepared with standard order (pH 7.0~7.4) have obvious influences on the measurement of Co (II) under shaking conditions (37°C, 120rpm), and the influence rates up to 43.46%, 40.32% and 18.03%, respectively. After the pH value of these media being adjusted to between 5 and 6, the influence rates were interestingly controlled in 5%. This picramazochrom spectrophotometry can be successfully applied to determine the Co (II) concentration in microbe media.


1980 ◽  
Vol 45 (1) ◽  
pp. 54-79 ◽  
Author(s):  
Petr Voznica ◽  
Josef Havel ◽  
Lumír Sommer

The complex equilibria of gallium, indium and thallium(III) with analytically important 2-(2-pyridylazo)-1-naphthol-4-sulphonate were studied spectrophotometrically using graphical analysis of the absorbance curves and minimization procedures for the absorbance data using the SPEKTFOT program on the Tesla 200 computer. The study yielded a complete picture of the reaction mechanism of these elements with heterocyclic azodyes. Optimum conditions for the spectrophotometric determination of gallium, indium and thallium using this reagent were found.


2009 ◽  
Vol 34 (2) ◽  
pp. 7-13 ◽  
Author(s):  
P. A. Antunes ◽  
G. Bannach ◽  
G. O. Chierice ◽  
E. T. G. Cavalheiro

A direct spectrophotometric method for simultaneous determination of Co(II) and Ni(II), with diethanoldithiocarbamate (DEDC) as complexing agent, is proposed using the maximum absorption at 360 and 638 nm (Co(II)/DEDC) and 390 nm (Ni/DEDC). Adjusting the best metal/ligand ratio, supporting eletrolite, pH, and time of analysis, linear analytical curves from 1.0 10-6-4.0 10-4 for Co(II) in the presence of Ni 1.0 10-6-1.0 10-4 mol L-1 were observed. No further treatment or calculation processes have been necessary. Recoveries in different mixing ratios were of 99%. Interference of Fe(III), Cu(II), Zn(II) and Cd(II), and anions as NO3-, Cl-, ClO4-, citrate and phosphate has been evaluated. The method was applied to natural waters spiked with the cations.


1980 ◽  
Vol 45 (5) ◽  
pp. 1525-1554 ◽  
Author(s):  
Viktor Kanický ◽  
Josef Havel ◽  
Lumír Sommer

This work is concerned with a detailed study of the reaction of UO2+2 with chromazurol S in the presence of cationic tenside Septonex, which was found to be very promising of the group of cationic tensides. From the study were drawn a number of conclusions regarding the effect of the cationic tenside on the reaction of triphenylmethane dyes with salicylic acid groups with metal cations. Optimum conditions for the spectrophotometric determination of uranium with chromazurol S in the presence of Septonex were found.


1981 ◽  
Vol 64 (3) ◽  
pp. 611-615 ◽  
Author(s):  
Saad S M Hassan

Abstract Simple, rapid, selective, and sensitive spectrophotometric methods are described for manual and semiautomated determination of vitamin K3. These methods are based on reactions with piperidine and malononitrile whereby intense red and blue colors with maximum absorption at 510 nm (E1%1cm 150) and 580 nm (E1%1cm 155), respectively, are developed. The reactions are sensitive enough to permit the determination of 2-100 μg vitamin K3/mL with an average recovery of 98% and a standard deviation of 1%. There is no interference from vitamins K1 and K2, and the reduced forms of K vitamins, or from many common pharmaceutical diluents and additives.


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