化学分析によるマンガン鉱石および還元マンガン鉱石中の各種成分の分別定量および組成分析

Abstract

In this report, the rational method of analysis by fractional determination of various elements, such as manganese, iron, silicon etc., in manganese and reduced manganese ores is discussed as based on the data described in the previous reports (Parts 1 to 8) is made. A method for fractional determination of manganese silicates in manganese and reduced manganese ores is also sought. After some experiments, a the following procedure for this purpose was decided upon as recommendable: Heat a 0.5 g sample of manganese or reduced manganese ore in a 50 mL solution of 18 N sulfuric acid with a small amount of hydrogen peroxide for an hour, in order to bring out all the manganese silicates (i.e. tephroite, braunite, penwithite etc.) in the sample except rhodonite in solution. The solution is then filtered after diluting with 200 mL of hot water, and adding a small amount of paper pulp; the residue containing rhodonite is washed thoroughly first with hot 0.5 N sulfuric acid solution, then, with water. The residue placed in a platimum crucible is ignited, fused with sodium carbonate, and extracted with sulfuric acid solution. The whole manganese in the extraction is determined by means of ferrous-permanganate titration, and the resultant manganese is calculated for rhodonite. The results of such analysis show that some trivalent manganese is contained only in some specific manganese ores such as braunite ore.