Ion chromatographic analysis

Other Methods. Ion chromatography using conductance detection can be used to measure low (<1%) levels of nitrite, chloride, sulfate, and other ions in nitric acid. Techniques for ion chromatographic analysis are available (93). 

Saari-Nordhaus, R. and Anderson, Jr., J. M., Ion chromatographic analysis of anions using a solid-phase chemical suppressor, Am. Lab., 26 (January), 28C, 1994. 

E. Sawicki, J.D. Mulik and E. Wattgenstein, Ion Chromatographic Analysis of Environmental Pollutants, Vol. 1, Ann Arbor Science, Ann Arbor, MI, 1978. 

Fig. 3.46. High-performance ion chromatographic analysis of C.I. Reactive yellow 84 after 120 min of the catalytic oxidation over Fe-Y80 catalyst. Initial conditions were 100 mg/1 azo-dye, pH 5, t = 50°C, catalyst concentration 1 g/1 and 20 mmol H202. Peak identities are as follows 1, acetate 2, formate 3, chloride (used for pH adjusting) 4, nitrate 5, malonate 6, sulphate 7, oxalate. Reprinted with permission from M. Neamtu et al. [121].

Mulik, J. D., Todd, G Estes, E., Puckett, R Sawicki, E., Ion Chromatographic Determination of Atmospheric Sulfur Dioxide. Ion Chromatographic Analysis of Environmental Pollutants. Edited by Sawicki, E., Mulik, f. D., Wittgenstein, E., Ann Arbor Science Publishers, Ann Arbor, MI (1978). 

Bjdrkholm E, Hultman A, Rudling J. 1988. Determination of chlorine and chlorine dioxide in workplace air by impinger collection and ion-chromatographic analysis. J Chromatogr 457 409-414. 

Mulik, J., R. Puckett, D. Williams, and E. Sawicki, Ion Chromatographic Analysis of Sulfate and Nitrate in Ambient Aerosols, Anal. Lett., 9, 653-663 (1976). 

Ion Chromatographic Analysis of Formic Acid in Diesel Exhaust and Mine Air... 

In order to prevent interference with such inorganic anions as fluoride, chloride, and nitrate which occurs with Na2C03/NaHC03 eluents, a weak aqueous eluent, i.e., Na2Bi+0y, was used to achieve adequate separation. The detection limit in such an ion chromatographic analysis is limited by the conductance of the suppressed eluents, but the development of ion chromatography exclusion (ICE),... 

Analytical Method. Initial experiments were conducted on the Dionex Model 14 ion chromatograph to determine the feasibility and sensitivity of ion chromatographic analysis of formic acid. 

Simplified analytical procedures for determination of gas-phase organic acids would be very beneficial. Currently, the acids are collected by using impregnated filters, denuder tubes, or water absorption techniques and then an ion chromatographic analysis. Normally, the collection and analysis steps are decoupled in time (i.e, samples collected at a field site are returned to a home laboratory for IC analysis). Once again, blank samples must be utilized to compensate for contamination during transport and storage prior to analysis. 

The technique has since 1975 progressed rapidly and in 1978 a book was published on Ion Chromatographic Analysis of Environmental Pollutants. Other early papers on the application of ion chromatography include the determination of selected ions in geothermal well water [7,8], the determination of anions in potable water [9] and the separation of metal ions and anions [10] and anions and cations [11]. 

Marko Varga et al. [45] found that a cleanup column prior to the separation column, packed with a chemically bonded amine material (Nucleosil 5 HN2) was found to be effective in removing interfering humic substances. No influence was found from humic substances in concentrations up to 45 pg L 1 on ion chromatographic analysis of nitrate and sulphate (10-100mg L ) after passage through the cleanup column. 

Slanina, J., Lingerak, W.A., Ondelmanm, J.E. etal. (eds,)Ion Chromatographic Analysis and Environmental Pollutants. Volume 2. Ann Arbor Science Publishers, Michigan (1979). 

The oxidation of S(IV) is a first order reaction with respect to S(IV) (2,3). This reaction is accelerated by the presence of metallic ions such as ferric and manganous ions which act as catalysts (4-8). Therefore, the effect of the metallic ions on the oxidation of S(IV) was investigated by using test solutions. Table I shows experimental conditions for the oxidation of S(IV) in test solutions. The pH values of synthetic rain water samples were adjusted between 3 and 6. S(IV) concentration in the test solutions was adjusted to 12.5 yM most of S(IV) existed as bisulfite at pH 3-6 (9). The rate of S(IV) oxidation was measured using ion chromatographic analysis. The pH of each test solution was adjusted by using a buffer. 

Deionized water (20 ml) containing a few drops of 30% hydrogen peroxide are placed in the bottom of the Schoniger flask and the flask is filled with oxygen. The combustion flask is introduced into an infrared igniter (available from A.H. Thomas Co.) and the wrapper is ignited. After combustion is complete, the flask is removed and allowed to cool for several minutes. The contents are shaken for 30 s and allowed to stand for about lh to ensure complete absorption. The solution is then transferred into a 100-ml volumetric flask and diluted to the mark with deionized water prior to ion chromatographic analysis. 

Cox, J.A., Dabex-Zlotorzynska, E., Saari, R. Tanaka, N. (1988) Ion exchange treatment of complicated samples prior to ion chromatographic analysis. Analyst 113, 109-250. 

Styrene/divinylbenzene copolymers are the most widely used substrate materials. Since they are stable in the pH range between 0 and 14, eluents with extreme pH values may be used. This allows the conversion of compounds such as carbohydrates, which are not ionic at neutral pH, into the anionic form, making them available for ion chromatographic analysis (see also Section 3.3.5.3). 

Ion chromatographic analysis methods ensure speed and high precision in the analysis of main components as well as of reaction and decomposition products in electroplating baths. The advantage of ion chromatography relative to the partly unspecific wet chemical methods utilized so far lies in the selectivity of the stationary phases and the detection systems being used. Thus, in most cases sample preparation is limited to a simple dilution with de-ionized water and subsequent filtration. A variety of applications on the basis of electrodeposition and electroless plating is summarized in Table 8-3. 

The sample preparation for ion chromatographic analysis of serums is much more elaborate. Proteins that are present in high concentration must be removed before the... 

For the ion chromatographic analysis of chloride in cement, that cancels out the passivation of steel surfaces in concrete and, thus, is only admitted up to a maximum content of 0.1%, Maurer et al. [93] developed a procedure in which the cement sample is extracted with nitric acid. Since a direct chloride determination is impossible due to the high nitrate concentration in the extract, silver nitrate is added in three-fold excess to the nitric acid extract. The precipitated silver chloride is filtered off and subsequently dissolved in 100 mL of a 0.25% ammonium hydroxide solution. This solution, according to the chloride concentration, can be further diluted with de-ionized water or injected directly. 

Several types of detectors used in ion chromatographic analysis along with a brief description of how the detectors operate are presented in this chapter. It is important to understand how detectors operate and how ions are detected. For example, detection of iodide in the presence of a salt (sodium chloride) matrix can be accomplished with conductivity detection. But UV detection would be much better due to the fact that iodide will absorb UV light and chloride will not. Because the detection is selective for iodide, the separation conditions can be optimized for rapid interference-free elution. 

S. Laksana and P. R. Haddad, Dialytic clean-up of alkaline samples prior to ion chromatographic analysis,/. Chromatogr., 602, 57,1992. 

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