Manganese spectrophotometric determination

Spectrophotometric determinations - continued D. or concn. of potassium nitrate, 710 D. of simultaneous, chromium and manganese, 712... 

Burke and Yoe (8) described the simultaneous spectrophotometric determination of cobalt and nickel in acidic ethanol. An analogous procedure in acidic dimethylformamide (DMF) was described by Ayers and Annand (3). By simultaneously solving Beer s law equations, the concentration of each metal can be determined (Eqs. 1 and 2). In general, the results of these two methods were similar. However, Burke and Yoe (8) found that iron and copper interfered with the measurement while Ayers and Annand (3) found interference from manganese. 

Bonilla E. 1978a. Flameless atomic absorption spectrophotometric determination of manganese in rat brain and other tissues. Clin Chem 24 471 -474. 

EXPERIMENT 25 SPECTROPHOTOMETRIC DETERMINATION OF MANGANESE AND CHROMIUM IN MIXTURE... 

The airborne aerosol is filtered and after the filter mineralization, manganese is determined in the solution by a spectrophotometric method following oxidation with periodate in acid medium to the red-violet MnO anion... 

Solvent extraction of manganese (III) and its spectrophotometric determination It was found that Mn(IIl) can be extracted from aqueous solution by dibutylphosphate in xylene and that the intensely coloured extracted solution has an absorption maximum at 537 nm (Polyhedron 13/14 (1989) 1874). 

Concentration limits of the diphosphate-ion, admissible to determination of magnesium and cobalt, manganese and cobalt, zinc and cobalt by spectrophotometric method with application of the l-(2-pyridylazo)-resorcinol (PAR) are presented. Exceeding maintenance of the diphosphate-ion higher admissible supposes a preliminary its separation on the anionite in the H+-form. The optimum conditions of cobalt determination and amount of the PAR, necessary for its full fastening are established on foundation of dependence of optical density of the cobalt complex with PAR from concentration Co + and pH (buffer solutions citrate-ammoniac and acetate-ammoniac). 

Nickel has been determined spectrophotometrically in seawater in amounts down to 0.5 xg/l as the dimethylglyoxime complex [521,522], In one procedure [521] dimethylglyoxime is added to a 750 ml sample and the pH adjusted to 9 -10. The nickel complex is extracted into chloroform. After extraction into 1M hydrochloric acid, it is oxidised with aqueous bromine, adjusted to pH 10.4, and dimethylglyoxime reagent added. It is made up to 50 ml and the extinction of the nickel complex measured at 442 nm. There is no serious interference from iron, cobalt, copper, or zinc but manganese may cause low results. 

After adjusting to 2 mol 1 1 in hydrochloric acid, 500 ml of the sample is adsorbed on a column of Dowex 1-XS resin (Cl form) and elution is then effected with 2 M nitric acid. The solution is evaporated to dryness after adding 1M hydrochloric acid, and the tin is again adsorbed on the same column. Tin is eluted with 2 M nitric acid, and determined in the eluate by the spectrophotometric catechol violet method. There is no interference from 0.1 mg of aluminium, manganese, nickel, copper, zinc, arsenic, cadmium, bismuth, or uranium any titanium, zirconium, or antimony are removed by ion exchange. Filtration of the sample through a Millipore filter does not affect the results, which are in agreement with those obtained by neutron activation analysis. 

Gine et al. [29] has described a semi-automatic determination of manganese in plant digests using flow injection analysis. This technique utilises the introduction of the sample into a continuously flowing carrier stream of formaldoxime reagent. When injected, the sample is pushed by this stream and dispersed into the reagent stream, whereupon the required reaction takes place. The coloured complex is then carried into a spectrophotometric flow cell, where the absorbance is measured after an exactly defined time interval. 

Heanes [97] has described a method for determining copper, manganese and zinc in ashed plant extracts by flame AA spectrophotometry after cobalt and molybdenum have been assayed on separate aliquots of the same plant extracts by a spectrophotometric procedure [102]. (See Sect. 7.34.3). Ashing aids were necessary to maintain accuracy in the determinations. Concentrations of up to 3.5% m/m of silicon and calcium and 4% m/m of chlorine in the plants did not affect the determinations, but in some instances lower concentrations were determined in plant samples containing equal or higher levels of both added silica and calcium. 

Nagaosa et al. [282] simultaneously determined aluminium, iron and manganese in non saline waters using high performance liquid chromatography with electrochemical and spectrophotometric detection. 

The present paper summarizes the oxidation-reduction chemistry of the gluconate complexes of Mn(II), Mn(III), and Mn(IV) in alkaline media. Electrochemical, spectrophotometric, and magnetic susceptibility measurements have been used to establish the formulas and chemical characteristics of the complexes. The oxidation-reduction chemistry for the manganese complexes formed by other ligands with polyhydroxyl functions also has been determined. 

The thiocyanate method has been used for determining cobalt in vitamin B12 [94], steel [24,94], and nickel [25]. Cobalt present in considerable amounts in alloys with aluminium, nickel, chromium, manganese, copper, and iron was determined by the differential spectrophotometric analysis [95]. 

The well-known and often-used spectrophotometric method for determining manganese, which is based on the coloured Mn04 ion, is highly selective but rather insensitive. Greater sensitivity is achieved in the method using formaldoxime. Even more sensitive is the... 

Pyridylazo)-2-naphthol (formula 4.1) reacts with Mn(ll) in weakly alkaline solution (pH 8-10) to form a chelate which is sparingly soluble in water. When the suspension is shaken with chloroform, the red-violet complex and the excess of the orange reagent pass into the organic layer. The coloured extract constitutes the basis of the extractive spectrophotometric method for determining manganese [26-28]. ... 

There are very sensitive catalytic spectrophotometric methods for the determination of manganese, in which traces of Mn(II) catalyse the oxidation of various organic substances by another oxidant (e.g., KIO4), with the formation of coloured reaction products. In these methods, the amount of colour depends on the reaction time. The catalytic effect of Mn on oxidation of Malachite Green by periodate has been utilised in determination of manganese by the FI A method [54—57]. 

M. Mesquita, A.O. Jacintho, E.A.G. Zagatto, R.F. Antonio, Autocatalysis in the spectrophotometric flow-injection determination of manganese as permanganate. Soil, plant and rock analysis, J. Braz. Chem. Soc. 1 (1990) 28. 

I.Y. Kolotyrkina, L.K. Shpigun, Y.A. Zolotov, G.I. Tsysin, Shipboard flow injection method for the determination of manganese in sea-water using in-valve preconcentration and catalytic spectrophotometric detection, Analyst 116 (1991) 707. 

Alternatively, the oxidising or reducing solid reagent can be immobilised on a suitable support, as demonstrated in the spectrophotometric and chemiluminometric flow injection determinations of manganese in natural waters using mini-columns of lead(IV) dioxide or sodium bis-muthate immobilised on silica gel beads [112] and paper pulp [113], respectively. 

Spectrophotometric methods have been described for the determination of copper, iron, cobalt and manganese in trichlorosilanes and in silicon tetrachloride186 boron in silicon tetrachloride and in hexachlorosilane187 and iron and aluminium in silicone polymers189. 

This field provides a brief description of the suggested monitoring and analysis method for quantitative determination of a particular substance. For example, a method for quantitative determination has been developed for cadmium, copper, manganese, and lead in water by means of co-precipitation with zirconium hydroxide followed by subsequent analysis by atomic adsorption spectrometry. An Inductively Coupled Plasma-Atomic Emission Spectrophotometric method has been employed by the Environmental Protection Agency (EPA Method 200.7) for the determination of dissolved, suspended, or total elements in drinking water, surface water, and domestic and industrial wastewaters. 

There are also test methods (ASTM, 2011k,w) for the analysis of coal (and coke) ash which cover the determination of nine major constituents of ash silicon dioxide, aluminum oxide, ferric oxide, titanium dioxide, phosphorous pentoxide, calcium oxide, magnesium oxide, sodium oxide, and potassium oxide (ASTM, 2011k) by a combination of spectrophotometric techniques, chelatometric techniques, and flame photometry. Determination of these same constituents, including manganese dioxide, can be achieved by atomic absorption (ASTM, 2011w). 

The complex is extracted with CCl /chlorobenzene (1 4) and determined spectrophotometrically at 365 nm (8 555 = 70 000). Due to the low antimony content in natural waters it is necessary to concentrate the element by coprecipitation with manganese dioxide hydrate. The addition of ethanol to the KMnOz solution improves the adsorption characteristics of the carrier. 

Another spectrophotometric method for determination of manganese oxide is based on the reaction of manganese with 1,2,4-trihydroxyanthraquinone (PURP) with an LOD of 68ngH. ... 

I.S. Balogh, L. Rusnakova, J. Skrlikova, M. Torok, V. Andruch, A spectrophotometric method for manganese determination in water samples based on ion pair formation and dispersive liquid-liquid microextraction, Int. J. Environ. Anal. Chem. (2011), http //dx.doi.org/10.1080/03067319.2010.537750. 

This method is the usual one for analysing the manganese content of steel. The initial step is to oxidise and remove organic matter (or O in steels). Persulphate then oxidises Mn to permanganate. The latter is then determined spectrophotometrically when dilution is necessary to obtain an optimum absorbance. The modification discussed in Sec.2.4.1 for strongly absorbing solutions could be used here. 

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