钛铁矿还原锈蚀法制取富钛料过程强化的基础研究

发布时间：2018-04-02 15:18

本文选题：钛铁矿　切入点：还原锈蚀法　出处：《中南大学》2011年硕士论文

【摘要】：随着金红石资源逐渐枯竭,价格低廉的钛铁矿已成为钛工业的主要生产原料,但钛铁矿的Ti02品位较低,一般需将其制备成高品位的富钛料。还原锈蚀法被认为是钛铁矿制取富钛料的一种有效方法,目前在工业中得到应用,但该法存在还原难度大,锈蚀时间长、生产效率低等问题。针对上述问题开展钛铁矿还原锈蚀法制取富钛料过程强化的基础研究,对于加快还原锈蚀法在钛铁矿制取富钛料工业生产中的推广应用具有重大意义。本文以攀西钛铁矿为原料,综合运用冶金动力学及电化学原理,结合X-射线衍射、光学显微镜和扫描电镜等现代微观测试手段,探讨了添加剂对钛铁矿还原锈蚀法制取富钛料的影响,深入研究了不同锈蚀体系对还原钛铁矿锈蚀行为及其对富钛料制备的影响；在此基础上系统研究了还原钛铁矿锈蚀速率过程的强化措施及铁副产品的物相控制与钛铁分离的关系,获得了以下主要结论： (1)钛铁矿配加添加剂对还原钛铁矿金属化率产生明显的影响,但对后续的锈蚀分离过程中非铁杂质的去除作用不大。对还原钛铁矿金属化率的影响是添加剂影响钛铁矿还原锈蚀法制取富钛料的主要原因。研究表明,适宜的添加剂为Na2CO3+Na2B4O7·10H2O,其适宜用量为Na2CO3 1.5%、Na2B4O7·10HzO 1.5%。 (2)还原钛铁矿的锈蚀体系选择研究发现,氟化氢铵+盐酸和氯化铵+盐酸有使还原钛铁矿锈蚀反应转变为浸出反应的倾向,适宜的锈蚀体系为氯化铵溶液。液固比、通气速率和温度是其主控因素。 (3)氯化铵锈蚀体系通入氧气是强化还原钛铁矿锈蚀反应速率过程的有效措施。动力学研究表明,还原钛铁矿中金属铁的锈蚀过程受内扩散控制,锈蚀体系通入氧气金属铁锈蚀过程的表观反应活化能由通入空气时的13.28 KJ·mol~(-1)降低至8.12 KJ·mol~(-1),通入氧气加快了其内扩散过程,促进了还原钛铁矿中金属铁锈蚀过程的阴极反应。 (4)还原钛铁矿锈蚀产物中铁副产品的物相影响后续钛铁分离效果,研究发现,形成针铁矿时钛铁分离效果最好,所得富钛料Ti02品位为77.81%,回收率为90%左右,产品粒度分布均匀,主要物相为酸溶性良好的黑钛石,是硫酸法生产钛白的优质原料。本论文的研究结果为提高钛铁矿还原锈蚀法制取富钛料生产效率提供了理论指导和技术支撑,对钛铁矿制取富钛料行业的技术进步具有积极的推动作用。
[Abstract]:With the gradual depletion of ilmenite rutile resources, low price has become the main raw materials for the production of titanium industry, but ilmenite Ti02 low grade, generally needs to be prepared into high grade titanium rich material. Reductive method is considered as an effective method of making titanium titanium rich material, the application of in the industry, but the existence of difficult reduction, long time corrosion, low production efficiency. In order to solve the above problems from ilmenite to carry out basic research of titanium rich material to enhance the process of reduction corrosion method, to speed up the reduction corrosion method in making titanium rich titanium material application in industrial production is of great significance.
In this paper, using Panxi ilmenite as raw materials, comprehensive utilization of metallurgical kinetics and electrochemical principle, combined with X- ray diffraction, optical microscopy and scanning electron microscopy and other modern microscopic test method, the effects of additives on ilmenite reduction corrosion method from titanium rich material, in-depth study of the different corrosion system of reduced ilmenite corrosion behavior and its influence on the titanium rich material preparation; and the relationship between Ti Fe separation control system based on the reduction of ilmenite corrosion rate process of strengthening measures and iron products, the main conclusions are as follows:
(1) ilmenite adding additives on reduction of ilmenite metallization rate have a significant impact, but has little effect on the removal of non rust iron impurity separation process in the follow-up. The effect of reduction of ilmenite metallization rate is mainly due to additive effect on ilmenite reduction corrosion method from titanium rich material. Research shows that suitable additives for Na2CO3+Na2B4O7 - 10H2O, the suitable dosage of Na2CO3 1.5%, Na2B4O7 10HzO 1.5%.
(2) the selection of corrosion system for reduced ilmenite has found that ammonium fluoride, hydrochloric acid and ammonium chloride + hydrochloric acid have the tendency to turn the corrosion reaction of reduced ilmenite into leaching reaction. The suitable corrosion system is ammonium chloride solution. The ratio of liquid to solid, ventilation rate and temperature are the main controlling factors.
(3) ammonium chloride corrosion system of oxygen is the effective way to strengthen the rust reaction rate of reduced ilmenite. Kinetic studies show that the reduction of corrosion process of metallic iron in ilmenite is controlled by internal diffusion, corrosion system into the process of oxygen corrosion of the metal rust apparent reaction activation energy by air at 13.28 KJ mol~ (-1) reduced to 8.12 KJ - mol~ (-1), oxygen diffusion rate in the process, promote the cathodic reaction of rust of metallic reduced ilmenite.
(4) the corrosion products of iron ilmenite by-product reduction phase influence subsequent Ti Fe separation effect, the study found that Ti Fe separation effect is the best form of goethite, the titanium rich material Ti02 grade is 77.81%, the recovery rate is about 90%, the product particle size distribution, the main phase is the acid soluble titanium black stone good, is a good raw material for sulfuric acid production of titanium dioxide.
The research results in this paper provide theoretical guidance and technical support for improving the production efficiency of ilmenite by reducing rust and preparing titanium rich materials, and play a positive role in promoting technological progress in ilmenite production.

【学位授予单位】：中南大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：TF823

【引证文献】