Ion-exclusion chromatographic behavior of aliphatic carboxylic acids and benzenecarboxylic acids on a sulfonated styrene--divinylbenzene co-polymer resin column with sulfuric acid containing various alcohols as eluent.
The addition of C1-C7 alcohols (methanol, ethanol, propanol, butanol, heptanol, hexanol and heptanol) to dilute sulfuric acid as eluent in ion-exclusion chromatography using a highly sulfonated styrene-divinylbenzene co-polymer resin (TSKgel SCX) in the H+ form as the stationary phase was carried out for the simultaneous separations of both (a) C1-C7 aliphatic carboxylic acids (formic, acetic, propionic, isobutyric, butyric, isovaleric, valeric, 2-methylvaleric, isocaproic, caproic, 2,2-dimethyl-n-valeric, 2-methylhexanoic, 5-methylhexanoic and heptanoic acids) and (b) benzenecarboxylic acids (pyromellitic, hemimellitic, trimellitic, o-phthalic, m-phthalic, p-phthalic, benzoic and salicylic acids and phenol). Heptanol was the most effective modifier in ion-exclusion chromatography for the improvement of peak shapes and a reduction in retention volumes for higher aliphatic carboxylic acids and benzenecarboxylic acids. Excellent simultaneous separation and relatively highly sensitive conductimetric detection for these C1-C7 aliphatic carboxylic acids were achieved on the TSKgel SCX column (150 x 6 mm I.D.) in 30 min using 0.5 mM sulfuric acid containing 0.025% heptanol as eluent. Excellent simultaneous separation and highly sensitive UV detection at 200 nm for these benzenecarboxylic acids were also achieved on the TSKgel SCX column in 30 min using 5 mM sulfuric acid containing 0.075% heptanol as eluent.
Ohta
Kazutoku
K
Ceramics Research Institute, National Institute of Advanced Industrial Science and Technology, 2266-98 Anagahora, Simoshidami, Moriyama-ku, Nagoya 463-8560, Japan. kazu.ohta@aist.go.jp
Towata
Atsuya
A
Ohashi
Masayoshi
M
D000438:Alcohols; D001555:Benzene Derivatives / Q000032:analysis; D002264:Carboxylic Acids / Q000032:analysis*; D002852:Chromatography, Ion Exchange / Q000379:methods*; D019850:Heptanol; D007202:Indicators and Reagents; D011108:Polymers; D011137:Polystyrenes; D012680:Sensitivity and Specificity; D013451:Sulfonic Acids; D013464:Sulfuric Acids
D000438:Alcohols; D001555:Benzene Derivatives; D002264:Carboxylic Acids; D007202:Indicators and Reagents; D011108:Polymers; D011137:Polystyrenes; D013451:Sulfonic Acids; D013464:Sulfuric Acids; C432006:divinylbenzene-polystyrene copolymer; D019850:Heptanol; C033158:sulfuric acid; C077114:styrenesulfonic acid polymer