(遼寧科技大學(xué) 材料冶金學(xué)院，遼寧 114051)
摘 要: 以淀粉作為還原劑，在一水硬鋁石水熱溶出的過(guò)程中同步還原氧化鐵，采用熱力學(xué)計(jì)算和實(shí)驗(yàn)研究氧化鐵在堿性溶液中的水熱還原行為。熱力學(xué)計(jì)算結(jié)果表明：在適當(dāng)?shù)难趸€原條件下，F(xiàn)e2O3可以轉(zhuǎn)化為Fe3O4。Fe2O3將溶于堿性水溶液中形成 ；在溫度大于373K的堿性水溶液中， 部分會(huì)轉(zhuǎn)化為 。淀粉在堿性水熱條件下通過(guò)降解，釋放醛基形成強(qiáng)還原體系，將Fe3+還原成Fe2+，F(xiàn)e3+進(jìn)一步與Fe2+反應(yīng)生成Fe3O4，該過(guò)程中溫度和堿濃度對(duì)Fe2O3的水熱還原有很大影響。當(dāng)處理溫度為260 ℃、堿濃度為210 g/L、時(shí)間為60 min、石灰與淀粉的用量分別為干礦石的7%和10%、磁性分離強(qiáng)度為0.08 T時(shí)，此時(shí)鋁溶出率為98.57%，鐵還原率為98.41%，磁選率為97.0%以上，F(xiàn)eT品位為73.5%。
關(guān)鍵字: 一水硬鋁石；赤鐵礦；淀粉；磁鐵礦；溶出；還原
（School of Materials and Metallurgy, University of Science and Technology Liaoning, Anshan 114051, China）
Abstract:The starch is used as a reducing agent to simultaneously reduce the iron oxide during the hydrothermal dissolution of the diaspore. The hydrothermal reduction behavior of iron oxide in alkaline solution were investigated by the thermodynamic calculation and experiments, the thermodynamic calculations show that Fe2O3 can be converted to Fe3O4 under appropriate redox conditions. Fe2O3 will dissolve in an alkaline aqueous solution to form , and part of the moiety will be converted to in an alkaline aqueous solution at temperature higher than 373 K. The starch is degraded under alkaline hydrothermal conditions, releasing an aldehyde group to form a strong reduction system and reducing Fe3+ to Fe2+, and Fe3+ further reacts with Fe2+ to form Fe3O4. The temperature and alkali concentration in this process have a great influence on the hydrothermal reduction of Fe2O3. The experimental results show that, when the treatment temperature is 260 ℃, the alkali concentration is 210 g/L, the time is 60 min, the amount of lime and starch is 7% and 10% of dry ore, respectively, and the magnetic separation strength is 0.08 T. The aluminum dissolution rate is 98.57%, the iron reduction rate is 98.41%, the magnetic separation rate is 97.0% or more, and the TFe grade is 73.5%.
Key words: diaspore; hematite; starch; magnetite; dissolution; reduction
