Organic anions, tartrate, maleate, malonate, citrate, glycollate, formate and fumarate

2 Organic anions, tartrate, maleate, malonate, citrate, glycollate, formate and fumarate 

Okada [5] employed a Redox suppressor in his ion exclusion chromatographic determination of tartrate, maleate, malonate, citrate, glycollate, formate and fumarate in non saline waters. A conductiometric detector was employed. 

Kim and Kim [6] have described an extremely sensitive determination of nitrite in drinking water (tap water and underground water) and envirorunental samples (rain, lake water, and soil) by ion exclusion chromatography with electrochemical detection. Potential interferences in the determination of nitrite by the standard spectrophotometric method or by the ion exchange chromatographic method with either conductivity or ultraviolet detection were eliminated. The detection limit was O.lpg L without preconcentration. 

Ion exclusion chromatography provides a convenient way to separate molecular acids from highly ionised substances. The separation column is packed with a cation exchange resin in the H form so that salts are converted to the corresponding acid. Ionised acids pass rapidly through the column while molecular acids are held up to varying degrees. A conductivity detector is commonly used. 

Tanaka et al. [7-9] have reported that the separation of phosphate from chloride, sulphate and several condensated phosphates (pyro- 

---