Determination of alkaline earth metals in offshore oil-well brines using high-performance chelation ion chromatography

Abstract

High-performance chelation ion chromatography (HPCIC) using chelating-dye impregnated resin has been developed as a novel technique for the quantitative determination of alkaline earth metals in oil-well brines. Detection limits of 1 mg dm^–3 for barium in samples containing over 1600 mg dm^–3 of calcium and up to 3% of sodium have been achieved. Three brine samples were investigated and levels of Ba²⁺, Si²⁺, Mg²⁺ and Ca²⁺ were determined in each. The results compared well with inductively coupled plasma optical emission spectrometry (ICP-OES).