Cationics analysis

Garda-Armada, P. Losada, J. de Vicente-Perez, S. Cation Analysis Scheme by Differential Pulse Polarography, /. 

Faubli, M. W. and Kampus, B., Cation analysis on a new poly(butadiene-maleic acid)-based column, /. Chromatogr. A, 706, 99, 1995. 

A common problem of cation analysis is the quality of the water used for rinsing the capillary. Sodium is a common contaminant in purified water, but it can also come from improper handling. 

From 1993 to the present, several publications have described anion and cation analysis for determination of pharmaceutical counterions (Pigure 16). and impurity profiling. For these applications, several buffers were used on different CE instruments. In most cases, detection was indirect or direct UV detection for analytes such as bromide that do absorb at 200 nm. Two papers describe use of a conductivity detector. 

Water samples were collected in midsummer, precipitation-free periods, following protocols of Ficklin Mosier (1999). On-site measurements include pH, specific conductance, alkalinity, acidity, dissolved oxygen, turbidity, and water temperature. Samples were collected in 1-litre polypropylene bottles and filtered onsite (0.45 pm) with disposable filters. Subsamples for cation analysis were placed in acid-rinsed polypropylene bottles and acidified with ultra-pure HNO3. Filtered, unacidified sub-samples for anion analysis were refrigerated until analyzed. In 2007, samples for Hg analysis were collected no Hg was detected at detection limits of 0.02 pg/L, precluding collection in 2008. 

In soil analysis, the sample pretreatment varies depending on whether a total elemental analysis or an exchangeable cation analysis is required. In the former, a silicate analysis method (see below) is appropriate. In the latter, the soil is shaken with an extractant solution, e.g. 1 M ammonium acetate, ammonium chloride or disodium EDTA. After filtration, the extractant solution is analysed. Fertilizers and crops can be treated as chemical and food samples, respectively. 

Three Co(II)Y zeolites with different cobalt concentrations were prepared from a Linde NaY zeolite (lot no. 13544-76) by conventional ion-exchange. A cation analysis of the Co(II)Y zeolites indicated concentrations of 0.8, 5, and 16 Co2+ ions per unit cell. 

The determination of aluminium is also discussed under Multi-Cation Analysis of Soils in Sects. 2.55 (inductively coupled plasma atomic emission spectrometry) and 2.55 (emission spectrometry). 

Various other techniques that have applied to the determination of antimony in multi-cation analysis include atomic absorption spectrometry (Sect. 2.55), inductively coupled plasma atomic emission spectrometry (Sect. 2.55), neutron activation analysis (Sect. 2.55) and photon activation analysis (Sect. 2.55). 

Bower, C. A., F. F. Reihmeier, and M. Fireman. 1952. Exchangeable cation analysis of saline and alkali soils. Soil Sci. 73 251-261. 

If phosphate has been detected previously (e.g. in the cation analysis), a qualitative test for arsenate may be made as follows. Pour 1 ml AgN03 solution, to which 2 drops of dilute acetic acid have been added, over the white precipitate. A brownish-red colouration of the precipitate confirms the presence of arsenate. The acetic acid is added to increase the solubility of the magnesium salt and thus facilitate the conversion of magnesium ammonium arsenate to the characteristic silver arsenate. 

Frodyma, M. M., Zaye, D. F., Van Lien, T. Cation analysis by thin-layer chromatography and reflectance spectroscopy. Part II. The determination of copper, nickel and zinc. Anal. Chim. Acta 40, 451 (1968)... 

Cation Analysis (Figure 9.6a). Suppose a dilute acid HY is used to elute a cation mixture in the order B , C, D. The suppressor column contains a finely graded conventional anion exchange resin in, say, the hydroxide form. Prior to elution of ion B, the suppressor column sees only the eluant HY, and the following exchange takes place ... 

For anion analysis, the regenerant must supply a source of hydrogen ions to convert the eluent anions to a less conductive form. The most common regenerant is dilute sulfuric acid, whereas for cation analysis, the most common regenerant is hydroxide (sodium, potassium, or tetramethylammonium hydroxide). 

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