DETERMINATION OF EQUILIBRIUM CONSTANT OF Ce-O OR Nd-O IN LIQUID IRON
Han Qiyong;Liu Shiwei;Niu Hongbing;Tang Zhiwei Beijing University of Iron and Steel Technology
Cite this article:
Han Qiyong;Liu Shiwei;Niu Hongbing;Tang Zhiwei Beijing University of Iron and Steel Technology. DETERMINATION OF EQUILIBRIUM CONSTANT OF Ce-O OR Nd-O IN LIQUID IRON. Acta Metall Sin, 1982, 18(2): 176-186.
Abstract Autoradiographs have shown that there is an obvious reaction between Ce and Nd in liquid iron and MgO,CaO crucible wall.For reaching the Ce-O, Nd-O equilibrium,a long smelting period and the adding of rare earth elements in several batches were needed to ensure the full reaction between the rare earth elements in melt and the crucible wall.The dissolved Ce or Nd content in iron was measured by means of radioactive isotopes ~(141)Ce or ~(147)Nd together with electrolysis in the organic electrolyte of samples.The oxygen activity was measured by solid electrolyte sensors made of ZrO_2(MgO) tube. Ce_2O_(3(s))=2[Ce]+3[O] △G*_(Ce_2O_3)=451150-161.68T lgK_(Ce_2O_3)=-(98611)/T+35.34 Nd_2O_3=2[Nd]+3[O] △G*_(Nd_2O_3)=375010-123.7T lgK_(Nd_2O_3)=-(81970)/T+27.04 The standard free energy of dissolution of Nd in liquid iron: Nd_(1)=[Nd]1% △G=19790-30.40T lgγ*_(Nd)=(4326.1)/T-4.154.
