Wettability and Reduction of MnO in Slag by Carbonaceous Materials

Reduction of MnO from slag and wetting of carbonaceous materials were studied in reaction of synthetic and industrial ferromanganese slags with graphite and coke substrates by the sessile drop method at 1 450-1 550°C. Reduced metal was found at slag-substrate interface and at gas-slag-substrate boundary of slag perimeter. The reduced metal was mainly manganese with small amount of dissolved silicon and carbon. The reduction rate of MnO increased with increasing activity of MnO in slag and temperature. The rate of MnO reduction from industrial slag was faster than from the synthetic slag; slag was more reactive with coke substrate than with graphite substrate. The reduction rate was observed to increase with increasing ash content in the substrate. The dynamic contact angle between carbon substrate and slag varied in a range of 80° to 140° and it decreased in the process of reaction. Lower contact angle was observed for a substrate with higher ash content.