平顶山高岭土的除铁增白实验研究

De-ironing and Bleaching Process of Kaolin from Pingdingshan

为了克服单一传统化学除铁方法的缺点,实验采用提纯剂提纯、保险粉除铁和煅烧除杂相结合的方法,并研究了提纯剂、保险粉、草酸的用量及煅烧温度等诸因素对平顶山高岭土除铁增白的影响,得到了最优的除铁增白方法。矿浆浓度10%,配比为2:1(wt.%)的柠檬酸钠和Na OH组成的提纯剂加入量为0.5wt.%,保险粉的用量3wt.%,草酸的量为1.5wt.%,800℃条件下煅烧。试样中Fe_2O_3的含量由1.08%降低到0.31%,白度值由59.3°提高到了85.7°。

In order to overcome the shortcoming of the chemical method of removing iron, refined kaolin was obtained by purifying with sodium citrate and NaOH mixed to 2:1, de-ironing with Na2S2O4 and calcination. The influences of the dosages of the purification agents,Na2S2O4, and oxalic acid, calcination temperature, etc. on the iron removal and bleaching result of Pingdingshan kaolin were investigated.The best iron removal and bleaching solution was discovered. When the concentration of the mineral slurry was 10%, the dosage of the purification agents was 0.5wt.%, the dosage of Na2S2O4 was 3wt.%, the dosage of oxalic acid was 1.5wt.%, and the calcinations temperature was 800 ℃, the mass fraction of Fe2O3 in kaolin dropped from1.08% to 0.31%, and the kaolin whiteness increased from 59.3° to 85.7°.