Rapid determination of organic acids in bauxite from Laos by RP-HPLC after solid phase extraction

Abstract

A rapid revised phase high performance liquid chromatographic method for the determination of organic acids in bauxite was reported. Oxalic, malonic, acetic, succinic, glutaric and adipic acid were separated and quantified in 10 min. First time repeatability, reproducibility and recoveries were determined for these acids in bauxite. The organic acids were removed from bauxite using a solid phase extraction procedure with anion exchange cartridges. The chromatographic separation was achieved with only one Kromasil RP-C₁₈ column thermostated at 25°C. Organic acids were detected with a UV VIS detector (215 nm). The precision results showed that the relative standard deviations of the repeatability and reproducibility were, <2·13 and, <3·24% respectively. The accuracy of the method was confirmed with an average recovery ranging between 89·2 and 114·7%. Under optimum conditions the detection limits ranged from 0·042 to 10·36 mg L⁻¹.