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采用热重-差热、X射线衍射及化学分析等方法，对包头矿添加15％（质量分数）碳酸钠焙烧反应进行了研究。在623～741K，稀土氟碳酸盐（RECO3F）首先分解为REOF；在853～928K，稀土磷酸盐（REPO4）与碳酸钠反应分解为RE2O3，并生成Ca8Nd2(PO4）6O2。焙烧反应动力学计算结果为：在623～741K，反应活化能E＝152kJ·mol(－1)．反应级数n＝0．77，反应频率因子A＝1．11×10(12)s(－1)·mol(－1)，705K时反应速率常数k＝1．102；在853－928K，E=232kJ·mol(－1)，n＝1.16，A＝1．11×109s(-1)·mol(-1)，915K时反应速率常数k=1．07×10(-4)。由热重曲线推断，两阶段反应机制方程式均为：F1=-ln（1-α）。
The roasting reaction of 15% (mass fraction) sodium carbonate in Baotou ore was studied by TG-DTA, X-ray diffraction and chemical analysis. At 623-741 K, rare earth fluorocarbonate (RECO3F) decomposed to REOF first. At 853-928 K, REO4 and sodium carbonate decomposed to RE2O3 and formed Ca8Nd2 (PO4) 6O2. Calcination reaction kinetics results: at 623 ~ 741K, the activation energy E = 152kJ · mol (-1). The reaction order was n = 0.77, the reaction frequency factor A was 1.11 × 10 12 s -1 -1 mol -1, and the reaction rate constant was k = 1.102 at 705 K. At 853-928 K, E = 232 kJ · mol -1, n = 1.16 and A = 1.11 × 109 s -1. The reaction rate constant k = 1.07 × 10 (-4) at 915K. From the thermogravimetry curve deduced, the two-stage reaction mechanism equation are: F1 = -ln (1-α).