Abstract
Exchange reactions of iron, manganese and silicon between molten slag and alloy were studied using radioactive isotope of each element. Small amount of slag containing one or two radioactive elements was added to the previously epuilibrated slag-metal system, and the exchange rate of the elements was determined from the change of the specific radioactivity in the metal phase. The results are summarized as follows:
(1) Amounts of elements which transfer from slag to alloy, or vice versa under equilibrium were determined as 2.3×10-2, 6.2×10-4 and 7.3×10-5g/cm2 sec for iron, manganese and silicon, respectively. These values were also valid for non-equilibrium states.
(2) Mass transfer coefficients of iron or manganese in the system of FeO-MnO slag over Fe-OMn alloy were obtained as 1.1×10-2cm/sec in the slag layer and 3.2×10-2cm/sec in the alloy layer. This was enabled by the simultaneous employment of radioactive iron and mangenese in one melting.
(3) Although the rate of the exchange reaction of silicon obtained in the system of CaO-SiO2 slag over Fe-O-Si alloy is small compared with that of iron or manganese, it is still larger than the rateof the reduction of SiO2 by carbon in blast-furnace-type slage. The small exchange rate of silicon can be attributed to the slow transfer of silicon ions in the slag phase.
