Two-dimensional conductometric detection in ion chromatography. Sequential suppressed and single column detection

Journal Article · Sat May 01 04:00:00 EDT 1993 · Analytical Chemistry (Washington); (United States)

DOI:https://doi.org/10.1021/ac00057a015· OSTI ID:6075746

Berglund, I; Dasgupta, P K; Lopez, J L; Nara, Osamu ^[1]

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1. Texas Tech Univ., Lubbock (United States)

A novel approach to simultaneously practicing both suppressed and nonsuppressed ion chromatography (IC) is proposed. Following the detector of a conventional NaOH eluent suppressed IC system, a constant concentration of NaOH is introduced by an in-line microelectrodialytic NaOH generator, and this is followed by a second conductivity detector. The second detector background is typically maintained at a level of 20-30 [mu]m/cm (corresponding approximately to 0.1 mM NaOH), and the detector output is the same as what would be observed in a single column mode with a low concentration NaOH eluent. Together, the two detector outputs provide detectabilities at the microgram per liter level across the pK[sub a] range-from fully dissociated to very weak acids (up to pK[sub a] 9.5). Excellent linearity of response is observed, and the system provides qualitative information about peak purity and eluite pK[sub a]. In addition to the usual ratio plots, it is suggested that multidimensional detection in any separation system is best served by plotting the raw detector outputs against each other. 16 refs., 11 figs.

• DOE Contract Number: FG05-84ER13281
• OSTI ID: 6075746
• Journal Information: Analytical Chemistry (Washington); (United States), Journal Name: Analytical Chemistry (Washington); (United States) Vol. 65:9; ISSN 0003-2700; ISSN ANCHAM
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400100* -- Analytical & Separations Chemistry
400201 -- Chemical & Physicochemical Properties
ALKALI METAL COMPOUNDS
CHROMATOGRAPHY
DETECTION
DIALYSIS
ELECTRIC CONDUCTIVITY
ELECTRIC MEASURING INSTRUMENTS
ELECTRICAL EQUIPMENT
ELECTRICAL PROPERTIES
ELECTRODIALYSIS
EQUIPMENT
HYDROGEN COMPOUNDS
HYDROXIDES
ION EXCHANGE CHROMATOGRAPHY
MEASURING INSTRUMENTS
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
SEPARATION PROCESSES
SODIUM COMPOUNDS
SODIUM HYDROXIDES
TWO-DIMENSIONAL CALCULATIONS