Reduction of barium and strontium from sulfates by carbon cast iron

It is known that the behavior of barium and strontium in liquid iron-carbon alloys requires further study. These elements practically do not form solutions with iron and are quickly removed from the melt. The deoxidizing and desulfurizing ability of the alloys of barium and strontium is low because of the large atomic mass of these elements. Nevertheless, it is known that barium and strontium have a significant effect on the properties of the melt, its structure, the number and shape of nonmetallic inclusions. This is, apparently, due to the ability of barium and strontium to affect the magnitude of interfacial tension in the event of contact with the phase boundary. The most accessible type of barium strontium-containing raw materials are alkaline earth metal sulfates. Thus, strontium barium sulfates are widely used in the production of modifiers and ferroalloys. When using sulfate raw materials for the production of barium strontium-containing alloys, one of the most important issues is the behavior of sulfur. In the literature, information is given on the thermodynamics and kinetics of reactions occurring during the re-firing of calcium, strontium and barium sulfates. Thermodynamic analysis of the reactions in the MeS04 - C (Me - Sr, Ba) system is also given. The probability of occurrence of these or those reactions depending on temperature is predicted. The purpose of this work was to study the behavior of sulfates of barium and strontium in liquid iron. Experimental work was carried out on the processing of molten iron by sulfates of barium and strontium under various conditions. The obtained experimental data make it possible to calculate the coefficients of sulfur transfer from sulfates to liquid iron and to trace the correlation with the thermodynamic data obtained for solid-phase processes.