Reduction Kinetics of FeTiO3 Powder by Hydrogen

Abstract

The reduction kinetics of FeTiO3 powder by hydrogen has been studied. According to the isothermal reduction experiments at the temperatures of 1 023 K, 1 073 K, 1 123 K and 1 173 K, it was found that the reduction products were mainly Fe and TiO2. During the reduction process, chemical reaction was found to be the rate controlling step. Meanwhile, the particle size distribution of FeTiO3 powder has a significant influence on the reduction kinetics.

Removing Tin from Tin-bearing Iron Concentrates with Sulfidation Roasting Using High Sulfur Coal

“…10) High sulfur coal was used as reducing and curing agents in this study, and its addition amount was represented as quality ratio of high sulfur coal to tin-bearing iron concentrates. Four factors of roasting temperature, residence time, high sulfur coal addition amounts and particles were chosen for studying the effects on the tin removal rate from tin-bearing iron concentrates.…”

“…External diffusion is not the rate controlling step when the gas flow rate is above 60 ml/min at high roasting temperature. 10) Therefore, the reaction rate is likely controlled by interfacial chemical reaction, gas internal diffusion or the combination of them. The reaction kinetic equations for different controlling steps are given in Table 4.…”

Reduction mechanism of high-chromium vanadium–titanium magnetite pellets by H2–CO–CO2 gas mixtures

“…Therefore, the unreacted core model applied in the work is presented as Eq. (9). The relationship between the reduction time and the restriction step is listed in Table 4.…”

Influence of Pre-oxidation on Carbothermic Reduction Process of Ilmenite Concentrate

“…(6), where Δm' is the weight loss at time t; ∆ ′ m max is the maximum weight loss. Chou model 11,12) (Eq. (7)) under the rate controlling step of diffusion in the solid product layer was used for dynamic curve fitting, where k' is a constant for a fixed material, μm 2 /s; E diff is the activation energy, J/mol; R is the gas constant, 8.314 J/(mol·K); T is the absolute temperature, K; t is the time, s; R 0 is the initial radius of particle, μm.…”