The kinetics of low-temperature (900–1180°C) reduction of iron tantalate (98.2 wt % FeTa_(2)O_(6), 1.8?wt % Ta_(2)O_(5), and particle size 0.1 mm) with an excess of aluminum (particle size 0.14 mm) and Al?:?FeTa_(2)O_(6)molar ratio equal to 6 is studied. The differential scanning calorimetry and X-ray phase analysis data show that the reduction process terminates approximately at 1180°C to form TaFeAl, TaAl_(3), and Ta_(17)Al_(12)metal products. The thermokinetic calculations (Ozawa–Flynn–Wall and nonlinear regression methods) indicate that the formal mechanism of the process is as a Bna → CnC scheme, which includes two successive stages controlled by the reactions activated autocatalytically. The kinetic parameters of the stages are as follows: (1) Е _(1)= 429 kJ mol~(–1)and A _(1)= 10~(15.3)s~(–1)and (2) Е _(2)= 176 kJ mol~(–1)and A _(2)= 10~(3.9)s~(–1)(where Е _( j )is the activation energy and A _( j )is the pre-exponential factor). The prediction within the Bna → CnC model indicates that the reaction mixture containing ≥98 mol % of a formal final reduction product may be obtained within 1040–1120°C over a period of 1.5–5 min. The proposed model can be used to develop scientific foundations and to substantiate technological modes of obtaining tantalum alloys from mineral and technogenic raw materials.
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