Abstract
CaO-Al2O3 binary slag and carbon saturated iron were melted in a graphite crucible and then reacted with nitrogen. In this experimental condition, complicated reactions took place electrochemically among gas, slag, metal and graphite. This study was made to determine the behavior of anions as nitride (N3−), cyanide (CN−) and carbide (C22−) in slag and N and Al in metal.
(1) Within a short reaction time (60 min), the rate of absorption of N3− and CN− in slag can be given by d(N)⁄dt=k′.
(2) The temperature dependence of absorption of nitrogen in slag melted with metal is larger than without metal.
(3) As the content of alumina in slag increases, the rate of absorption of nitrogen in slag is reduced but the rate of transfer of nitrogen from slag to metal increases.
(4) With increasing initial content of Al in metal, the transfer of nitrogen from slag to metal slows down while the absorption of nitrogen in slag is accelerated.
(5) As the reaction proceeds over a long time (10 hr), the components in slag and metal show a complicated behavior which can be divided into three stages in some cases.
(6) These results can be qualitatively explained by the electrochemical theory.
