Reduction analysis of carbon-coated nanometer iron oxides with different morphologies
HAO Su-ju1, GAO Yi-ce1, JIANG Wu-feng1, SUN Tian-hao1, ZHANG Yu-zhu1, BO He2
1. Ministry of Education Key Laboratory of Modern Metallurgy Technology, College of Metallurgy and Energy, North China University of Science and Technology, Tangshan 063009, Hebei, China; 2. School of Materials Engineering, Tangshan Vocational College of Science and Technology, Tangshan 063001, Hebei, China
Abstract:In order to inhibit the growth of iron whiskers during the reduction of iron ore powder, the spherical and rod-shaped nano-iron oxides with different morphologies were carbon-coated by hydrothermal carbonization, and the reduction behavior of carbon-coated iron oxides was studied by thermogravimetric method. Field emission scanning electron microscope (FE-SEM) was used to analyze the morphology of iron oxide and carbon-coated iron oxide after reduction. The results show that compared with ordinary iron ore powder, the reduction temperature of nano-iron oxide is greatly reduced. The smaller the heating rate is, the more favorable the carbon precipitation reaction to proceed on the surface of iron oxide is. Spherical iron oxide is easier to generate whiskers during the reduction process than rod-shaped iron oxide. Carbon coating can effectively inhibit the generation of whiskers during the iron oxide reduction process.
Anton Pichler, Heinrich Mali, Friedemann Plaul, et al. Reduction behavior and structural evolution of iron ores in fluidized bed technologies—Part 2: Characterization and evaluation of worldwide traded fine iron ore brands[J]. Steel Research International, 2016, 87(5): 642.
[8]
ZHANG Tao, LEI Chao, ZHU Qing-shan. Reduction of fine iron ore via a two-step fluidized bed direct reduction process[J]. Powder Technology, 2014, 254: 1.
WANG Xing-juan, LIU Ran, FANG Jue. Experimental study on sticking behavior of fluidized bed in reduction process[J]. Advanced Materials Research, 2012(482/484): 1354.
GUO Lei, ZHONG Sheng-ping, BAO Qi-peng, et al. Nucleation and growth of iron whiskers during gaseous reduction of hematite iron ore fines[J]. Metals, 2019, 9(7): 750.