自溶炉シャフト内における銅精鉱の酸化反応に関する基礎的研究

Abstract

Dry copper concentrates containing principally chalcopyrite and silica were flashed at 1300°C in a vertical reaction shaft to the products corresponding to the matte of 40 to 80% copper with the theoretical blast volume to concentrate ratios.The shaft products were examined by means of X-ray diffraction, microscopic observation, EPMA and chemical analysis.In the reaction shaft, iron and sulfur began to be oxidized with the mole ratio of iron/sulfur equal to 2/3 after chalcopyrite liberated only one eighth of its sulfur. The bulk of iron oxide was magnetite.When the copper content in residual sulfide reached about 50%, oxidation of copper sulfide to cuprous oxide proceeded in much smaller amounts than iron oxidation.The ratios of Fe3+ (O)% to Fe2+ (O)% in the shaft products from the copper concentrate containing 5% silica were higher than those from the copper concentrate containing 10% silica. On the contrary, the fractions of copper oxidized in the former were lower than those in the latter.