Applications

Compared to other separation methods such as ion exclusion chromatography, anion exchange provides improved selectivity within the three groups of acids: mono-, di- and tricarboxylic acids. This is particularly true among the stronger acids such as most of

Time (min)

Figure 7 Example of a gradient separation of inorganic and organic acid anions by anion exchange chromatography. A Dionex lonPac AS11 column was used with a mobile phase comprising water and NaOH as a gradient. Detection was by conductivity in the suppressed mode. Solute identities: 1, isopropylethylphosphonicacid; 2, quinate; 3, fluoride; 4, acetate; 5, propionate; 6, formate; 7, methylsulfonic acid; 8, pyruvate; 9, chlorite; 10, valerate; 11, monochloroacetate; 12, bromate; 13, chloride; 14, nitrite; 15, tri-fluoroacetate; 16, bromide; 17, nitrate; 18, chlorate; 19, selenite; 20, carbonate; 21, malonate; 22, maleate; 23, sulfate; 24, oxalate; 25, ketomalonate; 26, tungstate; 27, phthalate; 28; phosphate; 29, chromate; 30, citrate; 31, tricarballylate; 32, isocitrate; 33, cis-aconitate; 34, trans-aconitate. Chromatogram courtesy of Dionex Corporation Product Selection Guide (1997-98) 48.

Time (min)

Figure 7 Example of a gradient separation of inorganic and organic acid anions by anion exchange chromatography. A Dionex lonPac AS11 column was used with a mobile phase comprising water and NaOH as a gradient. Detection was by conductivity in the suppressed mode. Solute identities: 1, isopropylethylphosphonicacid; 2, quinate; 3, fluoride; 4, acetate; 5, propionate; 6, formate; 7, methylsulfonic acid; 8, pyruvate; 9, chlorite; 10, valerate; 11, monochloroacetate; 12, bromate; 13, chloride; 14, nitrite; 15, tri-fluoroacetate; 16, bromide; 17, nitrate; 18, chlorate; 19, selenite; 20, carbonate; 21, malonate; 22, maleate; 23, sulfate; 24, oxalate; 25, ketomalonate; 26, tungstate; 27, phthalate; 28; phosphate; 29, chromate; 30, citrate; 31, tricarballylate; 32, isocitrate; 33, cis-aconitate; 34, trans-aconitate. Chromatogram courtesy of Dionex Corporation Product Selection Guide (1997-98) 48.

the di- and tricarboxylic acids. Of the di- and tricarboxylic acids which are in the Krebs cycle or are commonly found in foods, there are only two groups of co-eluting acids: malic and malonic, and isocitric and cis-aconitic. Another advantage of anion exchange separation is the possibility of simultaneous determination of some inorganic ions, such as fluoride, chloride, and sulfate, with the carboxylic acids.

Applications of anion exchange chromatography of carboxylic acids include the quantification of short chain organic acids and inorganic anions for the biotechnology, chemical or power industries, the separation of the Krebs cycle acids in foods and beverages, and also the separation of aromatic carboxylic acids in chemical process solutions and as impurities in precursors in the polymer industry.

Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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