Production Of Nbc from Nb2O5 in a rotating cylinder reactor: Kinetic study of reduction/carburization reactions

The present work aims at a kinetic model for converting NbO2 into NbC in the isothermal region of the second reduction/carburization reaction. The model presented for the solid phase was based on the variation of the mass obtained for experiments with reactions interrupted at different times and processed at temperatures of 1148, 1173 and 1223 K. The reaction took place in a rotating cylinder reactor, with rotation velocity of 5 rpm, gas phase flow of 4.033 × 106 m3/s and initial mass of Nb2O5 0.004 kg (nominal).The conversion of NbO2 was found from the mass balances performed based on the set of stoichiometric equations of the reduction/carburization of Nb2O5 into NbC and used to validate the nucleation model using two parameters (N, M) which indicate, respectively, the tridimensional growth of the nuclei formed and a fourfold increase in the growth velocity of the nuclei.

► Production of NbC from Nb2O5 at low temperatures (1148–1223 K).
► Validation of Avrami's nucleation model for the reaction NbO2 into NbC.
► Use of a cylinder rotary reactor to carry out the reaction to produce NbC.