Mining, Metallurgy & Exploration ( IF 1.9 ) Pub Date : 2021-03-29 , DOI: 10.1007/s42461-021-00420-z T. Dilmi. U. Wijewardhana , H. C. S. Subasinghe , Amila Sandaruwan Ratnayake
The value addition potential of ilmenite was examined using several characterization techniques. Raw ilmenite is composed of 93.65 wt.% of FeOTiO2, 3.55 wt.% of SiO2, 1.22 wt.% of Al2O3, and the remainder being other minor oxides. Ilmenite and powdered carbonized coconut shells were mixed in the weight ratio of 4:1. A separate fraction of the same mixture was added with powdered seashells in the weight ratio of 4:1:0.5. Six fractions of each mixture were distinctly milled from 1 to 6 h in a planetary ball mill. XRD spectra (broadened and diminished reflections of ilmenite) and FTIR observations (Ti―O―C bonding) of milled samples indicate the possible incorporation of carbon into the ilmenite structure. Any clues of an occurrence of new rutile peaks were not observed in XRD spectra of milled samples. Consequently, the carbothermic reduction has not been initiated during mechanical activation. In this case, samples powdered for 6 h in a mill were isothermally annealed for 2 h under normal airflow at temperatures of 800 °C, 1000 °C, and 1200 °C, respectively. According to the X-ray diffractograms, the annealing temperatures of 1000 °C and 1200 °C exhibited almost similar trends with rutile (R), pseudobrookite (PB) and elemental iron (F), and a very few ilmenite (I) peaks. Consequently, 6 h of milling and 1000 °C annealing were concluded as the optimum conditions for the carbothermic reduction. Moreover, this study indicated seashells as a potential rate raiser for the carbothermic reduction of ilmenite at 800 °C. Therefore, this process is applicable to upgrade ilmenite into a mixture of synthetic rutile and elemental iron.
中文翻译:
使用碳化废椰子壳为钛铁矿增值:一种机械化学方法,以贝壳粉作为增产剂
使用多种表征技术检查了钛铁矿的增值潜力。原钛铁矿FeOTiO组成的93.65重量%2,3.55重量的SiO%2的Al,1.22%(重量)2 ö 3,其余为其他次要氧化物。将钛铁矿和粉末状碳化的椰子壳以4:1的重量比混合。将相同混合物的单独部分与粉末状贝壳一起以4:1:0.5的重量比添加。在行星式球磨机中从1到6 h分别研磨每种混合物的六部分。研磨样品的XRD光谱(钛铁矿反射变宽和减小)和FTIR观察(Ti-O-C键合)表明,碳可能混入钛铁矿结构中。在研磨样品的XRD谱图中未观察到任何新的金红石峰出现的线索。因此,在机械活化过程中尚未开始碳热还原。在这种情况下,将在磨机中粉化6小时的样品在正常气流下于800°C,1000°C,和1200°C。根据X射线衍射图,在1000°C和1200°C的退火温度下,金红石(R),假板钛矿(PB)和元素铁(F)以及很少的钛铁矿(I)峰表现出几乎相似的趋势。因此,总结了6个小时的研磨和1000°C的退火处理是进行碳热还原的最佳条件。此外,这项研究表明,贝壳是在800°C下钛铁矿的碳热还原的潜在速率提升剂。因此,该方法适用于将钛铁矿提质为合成金红石和元素铁的混合物。因此,总结了6个小时的研磨和1000°C的退火处理是进行碳热还原的最佳条件。此外,这项研究表明,贝壳是在800°C下钛铁矿的碳热还原的潜在速率提升剂。因此,该方法适用于将钛铁矿提质为合成金红石和元素铁的混合物。因此,总结了6个小时的研磨和1000°C的退火处理是进行碳热还原的最佳条件。此外,这项研究表明,贝壳是在800°C下钛铁矿的碳热还原的潜在速率提升剂。因此,该方法适用于将钛铁矿提质为合成金红石和元素铁的混合物。