The research on the mechanism of the roast reaction of Baotou concentrate of rare earth with 15% Na 2CO 3 additions was carried out through thermal, X ray diffraction and chemical analysis. Bastnaesite(RECO 3F) wa...The research on the mechanism of the roast reaction of Baotou concentrate of rare earth with 15% Na 2CO 3 additions was carried out through thermal, X ray diffraction and chemical analysis. Bastnaesite(RECO 3F) was first decomposed into REOF at 623～741 K, then Monazite(REPO 4) reacted with Na 2CO 3 was decomposed into RE 2O 3 and produced Ca 8Nd 2(PO 4) 6O 2 at 853～928 K. The kinetics parameters of the roast reaction were calculated. The results of the calculation were as follows: at 623～741 K, E =152 kJ·mol -1 , n =0 77, A =1 11×10 12 s -1 ·mol -1 , k =1 102( T =705 K), and at 853～928 K, E =232 kJ·mol -1 , n =1 16, A =1 11×10 9 s -1 ·mol -1 , k =1 07×10 -4 ( T =915 K). The equation of the mechanism of the roast reaction is F 1=-ln(1- α ) at 623～741 K and 853～928 K according to TG curves.展开更多
文摘The research on the mechanism of the roast reaction of Baotou concentrate of rare earth with 15% Na 2CO 3 additions was carried out through thermal, X ray diffraction and chemical analysis. Bastnaesite(RECO 3F) was first decomposed into REOF at 623～741 K, then Monazite(REPO 4) reacted with Na 2CO 3 was decomposed into RE 2O 3 and produced Ca 8Nd 2(PO 4) 6O 2 at 853～928 K. The kinetics parameters of the roast reaction were calculated. The results of the calculation were as follows: at 623～741 K, E =152 kJ·mol -1 , n =0 77, A =1 11×10 12 s -1 ·mol -1 , k =1 102( T =705 K), and at 853～928 K, E =232 kJ·mol -1 , n =1 16, A =1 11×10 9 s -1 ·mol -1 , k =1 07×10 -4 ( T =915 K). The equation of the mechanism of the roast reaction is F 1=-ln(1- α ) at 623～741 K and 853～928 K according to TG curves.
