含ニオブ溶融スラグのガスによる還元挙動

抄録

The behavior of gaseous reduction of molten slag containing niobium oxide was examined for the purpose of making ferro-niobium alloy of good quality.
The molten slag containing niobium oxide was reduced in the crucibles made of high purity magnesia or pure iron with H₂ gas, CO gas and H₂-CO gas mixtures. The results are as follows;
(1) Iron oxide and P₂O₅ in the slag were easily reduced with H₂ gas while they were slightly reduced with CO gas at 1 450°C.
(2) The slag elements except FeO, Fe₂O₃ and P₂O₅ were scarcely reduced with H₂ or CO gas in the temperature range from 1 350 to 1 550°C.
(3) The reduction of FeO with H₂ gas was accelerated by the increase in MgO content in slag.
(4) The relation between (%FeO) and (%P₂O₅) in reduced slags is expressed in the following equation:
(%P₂O₅)=0.037(%FeO)+ 0.04