钛铁矿选择氯化法制取人造金红石的热力学与动力学

THERMODYNAMICS AND KINETICS OF PRODUCING SYNTHETIC RUTILE BY SELECTIVE CHLORINATION OF ILMENITE

研究了钛铁矿选择氯化制取人造金红石反应的Fe-Ti-C-O2-Cl2系平衡图,计算了氧与某些氯化物相互作用的自由能变化,采用"通氧一步选择氯化法",解决了选择氯化"自热"反应持续进行的技术关键。对反应参数进行了实验室、半工业和工业化生产试验研究,研究证明:选择氯化过程的动力学模型是"固体颗粒粒度保持不变的缩核反应模型",动力学区的活化能为34.33kJ/mol;扩散区的活化能为0.80kJ/mol。研究开发的无筛板沸腾氯化炉可以长期稳定地连续运转,生产出的人造金红石品位为92.10%,经摇床和磁选,品位达到95%,床层单位炉产能达12.4t/(m2·d)。该工艺和设备已成功地应用于工业生产。

The phase equilibrium diagram of Fe-Ti-C-O2-Cl2 system is studied for the preparation of synthetic rutile by selective chlorination of ilmenite. The changes of free energy are calculated in the reactions between O2 and certain chlorides. By means of a process-'oxygen-induction one-step selective chlorinatio 'self-heating' chlorination. The technical parameters have been verified by lab-test, pilot test and industrial-scale test. The study has proved that the dynamic model of the selective chlorination process is a 'shrinking core reaction model in which the solids' particle size is kept unchanged', with the activation energy in the dynamic zone being 34.33 kJ/mol and that in the diffusion zone 0.8 kJ/mol. The fluidized bed chlorinator without perforated-plate developed in this process can stably and continuously operate in a long period of time. The process and the relevant equipment have been successfully applied in the industrial production, with the grade of resultant synthetic rutile being 92.1%, and even up to 95% through the additional table concentration and magnetic separation. The reactor's capacity can reach 12.4 t/m2·d. 