Nickel determination water

The use of peroxyacids, including PMSA, makes it possible to improve photometric method of nickel determination - to increase selectivity, accuracy and reproducibility of measurements. Peroxyacids as oxidants ai e used for nickel determination in aluminium and copper alloys, natural waters, stomatological products. 

Metal-free sodium citrate buffer solution for iron and nickel determination, 1.0 M Dissolve 147 g of sodium citrate dihydrate plus 105 g of citric acid monohydrate in water and dilute to ca. 900 ml. Add 10 drops of bromphenol blue indicator solution (13) and adjust the pH to 4.7. 

Table 2 Concentration of chromium and nickel, determined by AAS, in samples taken from four sources of waste waters...

Park, C. J., and Yim, S. A. (1999). Determination of nickel in water samples by isotope dilution inductively coupled plasma mass spectrometry with sample introduction by carbonyl vapor generotion.J. Anal. At. Spectrom. 14(7), 1061. 

This reagent, to which the name nioxime has been given, ia employed for the determination of palladium and may also be used for nickel it is soluble in water, and possesses advantages over dimethylglyoxime. The latter is used as a solution in alcohol and may therefore contaminate the palladium or nickel precipitate when added to an aqueous solution. 

The determination of tin in metals containing over 75 wt % tin (eg, ingot tin) requites a special procedure (17). A 5-g sample is dissolved in hydrochloric acid, reduced with nickel, and cooled in CO2. A calculated weight of pure potassium iodate (dried at 100°C) and an excess of potassium iodide (1 3) are dissolved in water and added to the reduced solution to oxidize 96—98 wt % of the stannous chloride present. The reaction is completed by titration with 0.1 Af KIO —KI solution to a blue color using starch as the indicator. 

The electrodes have a wide linear response range to CrP" and Ni " ions concentration. For this reason, they are adequate for the potentiometric determinations of copper and nickel ions in diluted solutions (dilutions may go down to 10 M) as well as in checking the industrial waters. 

Theory. Conventional anion and cation exchange resins appear to be of limited use for concentrating trace metals from saline solutions such as sea water. The introduction of chelating resins, particularly those based on iminodiacetic acid, makes it possible to concentrate trace metals from brine solutions and separate them from the major components of the solution. Thus the elements cadmium, copper, cobalt, nickel and zinc are selectively retained by the resin Chelex-100 and can be recovered subsequently for determination by atomic absorption spectrophotometry.45 To enhance the sensitivity of the AAS procedure the eluate is evaporated to dryness and the residue dissolved in 90 per cent aqueous acetone. The use of the chelating resin offers the advantage over concentration by solvent extraction that, in principle, there is no limit to the volume of sample which can be used. 

A process for the gravimetric determination of mixtures of selenium and tellurium is also described. Selenium and tellurium occur in practice either as the impure elements or as selenides or tellurides. They may be brought into solution by mixing intimately with 2 parts of sodium carbonate and 1 part of potassium nitrate in a nickel crucible, covering with a layer of the mixture, and then heating gradually to fusion. The cold melt is extracted with water, and filtered. The elements are then determined in the filtrate. 

This procedure has been utihzed to determine metal cations and anions in water sample [48,50,51], titanium in high-speed steel at a concentration level of 25 3 mg/g [22], heavy metals (20 to 400 mg/1) in electroplating waste waters [25], copper and nickel (5 mg/1) in metal electroplating baths on wedge-shaped plates [44], copper, lead, cadmium, or mercury in vegetable juices [29], and nickel (1 to 3.8 mg/1) in electroplating waste water of lock industries [42,47]. 

Quevauviller Ph, Kramer KJM, Vinhas T (1996) Certified reference material for the quality control of cadmium, copper, nickel and zinc determination in estuarine water (CRM 505). Fresenius J Anal Chem 354 397-404. 

Acar 0, Kn ic Z, Turker AR (1999) Determination of bismuth, indium and lead in geological and sea-water samples by electrothermal atomic absorption spectrometry with nickel containing chemical modifiers. Anal Chim Acta 382 329-338. 

Miscellaneous Reactions of Phosphines.- The role of chiral phosphines as ligands in the catalysis of reactions leading to the formation of chiral products has been reviewed.1111 A procedure for the determination of the enantiomeric excess in chiral phosphines has been developed, based on 13C n.m.r. studies of the diastereoisomeric complexes formed by phosphines with the chiral pinenyl nickel bromide complex. 111 Studies of the sulphonation of triphenylphosphine and of chiral arylphosphines have been reported in attempts to prepare water soluble ligands which aid... 

Xu Y, Liang Y. 1997. Combined nickel and phosphate modifier for lead determination in water by electrothermal atomic absorption spectrometry. Journal of Analytical Atomic Spectrometry 12(4) 471-474. 

Mapsi et al. [16] reported the use of a potentiometric method for the determination of the stability constants of miconazole complexes with iron(II), iron(III), cobalt(II), nickel(II), copper(II), and zinc(II) ions. The interaction of miconazole with the ions was determined potentiometrically in methanol-water (90 10) at an ionic force of 0.16 and at 20 °C. The coordination number of iron, cobalt, and nickel was 6 copper and zinc show a coordination number of 4. The values of the respected log jSn of these complexes were calculated by an improved Scatchard (1949) method and they are in agreement with the Irving-Williams (1953) series of Fe2+ < Co2+ < Ni2 < Cu2+ < Zn2+. 

The results obtained by various calibrations in the determination of nickel and copper are shown in Tables 1.2 and 1.3. Table 1.4 gives the differences between sampling devices for copper, as determined by each participant, when these are significant at the 95% and 90% levels of confidence. Only the results of participants that had acceptable analytical performance, as measured by precision and agreement with contemporary consensus values for deep North Atlantic waters (Table 1.5), were used for drawing conclusions. 

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