Spectrophotometric Determination of Silica in Metallurgical-Grade Fluorspar, Laboratory Method No. 14/42

摘要

A spectrophotometric method, based on a previously published Mintek report, is described for the determination of macro-amounts of silica in fluorspar-type materials. After the sample has been dissolved by fusion and treatment with acid, ammonium molybdate is added in the presence of tartaric acid to form a yellow silicomolybdate complex, which is measured spectrophotometrically. The precision (relative standard deviation) of the method is 0,012 in the silica concentration range 4 to 13 percent, and the accuracy is better than 98 percent. Ten determinations can be carried out in 8 hours.