焙烧针铁矿—菱铁矿精矿制备多孔赤铁矿吸附剂的研究

通过焙烧针铁矿菱铁矿精矿制备了一种良好的多孔赤铁矿吸附剂,并对其比表面积、孔径特性进行了分析和表征。对多孔赤铁矿制备过程中的影响因素包括焙烧温度、升温速率和保温时间进行了优化。结果表明:焙烧温度是影响吸附剂性能的最主要因素,过高的温度不仅消耗更多的能量,而且降低产物中微孔的数量,使得产物的比表面积减小;保温时间对吸附剂性能影响较大;升温速率对吸附剂性能影响不大;在焙烧温度为500℃,升温速率为10℃/min,保温时间为0.5h时制备得到产物性能最优,其总比表面积提高到103m^2/g,微孔比表面积升高到76m^2/g。

Porous Hematite Adsorbents Prepared by Thermal Modification of a Goethite-Siderite Concentrate

The preparation and pore characterization of porous hematite through thermal decomposition of goethite-sider ite concentrate have been performedin this study.The effect of calcinating temperature, temperature rising rateand residue time on the calcinated product was investigated and it has been found that calcinating temperature was the predominant factor on the preparation of the porous hematite. High temperatures not only led to the high energy consumption, but also reduced the micropores in the hematite. Also, residence time in the calcinations greatly affected the pore characterization of the porous he matite. But temperature increasing rate only had slight influence on the porous hematite. The optimized conditions were found at calcination time of 500 ℃, temperature increasing rateof 10 ℃/minand residence time of 0.5 h, where the prepared porous hematite showed the highest total specific area of 103 m^2/g and micro-pore specific area of 76 m^2/g.