Determination of free lime in clinker and cement by iodometry: an undergraduate experiment in redox titrimetry

An undergraduate experiment in redox titrimetry involving determination of free lime in clinker and cement using iodometry can teach students several skills, extraction, filtration, redox and acid-base titrations, and statistical data analysis.Free lime is first extracted with nonaqueous ethylene glycol, the suspension filtered and allowed to react with a known excess of hydrochloric acid and the excess acid determined by iodometry. In speed, sensitivity and precision, the method is better than the classical British Standard (BS) method, which is discussed. It shows students how traditional wet chemistry can be used in industry and lets students learn about cement processing.