Determination Of Calcium And Magnesium In Limestone And Dolomite By Enthalpimetric Flow-injection Analysis

A flow-enthalpimetric method for the determination of calcium and magnesium in limestone and dolomite is described. Calcium is determined by measuring the heat evolved from the substitution reaction with Mg-EDTA. The amount of magnesium is calculated from the calcium content and the enthalpimetric signal for the reaction of the sample solution with disodium-EDTA, which gives the total concentration of calcium and magnesium. Analysis of reference materials and other samples indicates an error not exceeding 0.3% of CaO and MgO, and a sampling rate of 100 samples per hour. © 1987.346543546Hitchen, Zechanowitsch, (1980) Talanta, 27, p. 269Jordan, Billingham, Jr., (1961) Anal. Chem., 33, p. 120Chatterji, (1955) J. Indian Chem. Soc., 32, p. 366Sajó, Sipos, (1968) Radex Rundsch., p. 178Pasquini, de Oliveira, (1984) Anal. Chim. Acta, 156, p. 307Schifreen, Miller, Carr, (1979) Anal. Chem., 51, p. 278Fo, Medeiros, Reis, Zagatto, (1978) Anal. Chim. Acta, 101, p. 9Jordan, Alleman, (1957) Anal. Chem., 29, p. 9Yoshida, Hattori, Arai, Taga, (1983) Anal. Chim. Acta, 152, p. 257Dancsi, Trischler, (1971) Z. Anal. Chem., 256, p. 12