Uber die Azotierreaktion von kornigem Calciumcarbid, V : der Reaktionsverlauf bei hoheren Reaktionsgraden

Abstract

The reaction at 1100℃ between nitrogen at atmospheric pressure and calcium carbide grains of uniform size mixed with various amounts x of calcium fluoride as an accelerator was followed to higher degrees of reaction than hitherto has been investigated. Another phase of the reaction has been found, where the radius of the grain considered as a sphere decreased again linearly with time. This constant rate of decrease S_2 has been expressed by a simple function of x and the temperature. It was verified that this reaction during the second phase is governed by essentially the same rate equations as the first phase reaction. A tentative mechanism of the second phase reaction has been proposed.