响应曲面优化某高岭土磁化焙烧除铁实验研究

Optimization Iron Removal by Magnetized Roasting of Kaolin Based on Response Surface Methodology

以贵州某高岭土矿为研究对象,在进行了XRD、化学多元素、铁物相分析后,铁主要以赤褐铁矿存在,决定采用磁选除铁达到增白的目的。由于高梯度磁选探索试验效果不理想,因此采用还原磁化焙烧法进行试验研究。以碱性竹炭法作为还原焙烧剂,Na HCO3作为降低焙烧温度的添加剂,硼酸作为增加高岭土磁性物质转变的活性剂,通过大量试验发现焙烧时间、焙烧温度、硼酸用量对质量磁化率的影响最大,通过Design-expert 10.0软件进行优化模拟该3个因素,确定焙烧时间69 min,焙烧温度465.7℃,硼酸用量2.173wt%进行试验。磁选除铁的高岭土矿增白后能得到白度为89.37%的可用于陶瓷等工业的高岭土产品。

A kaolin mine in Guizhou Province was taken as the research object.After XRD,chemical multi-element and iron phase analysis,iron mainly exists as limonite,and the purpose of using magnetic separation to remove iron is reached.Due to the unsatisfactory results of the high-gradient magnetic separation exploration test,the reduction magnetization roasting method is used to conduct the experimental study.Taking alkaline bamboo charcoal as reducing roasting agent,NaHC03 as additive to lower roasting temperature and boric acid as active agent to increase the transformation of magnetic material of kaolin,it is found through a large number of experiments that the influence of roasting time,roasting temperature and boric acid dosage on the mass magnetic susceptibility is maximized,Designexpert 10.0 software to optimize the simulation of these three factors,to determine the roasting time 69 min,calcination temperature 465.7℃,boric acid dosage 2.173wt%were tested.Magnetic separation of kaolin kaolin ore after whitening can be 89.37%whiteness can be used for ceramics and other industrial kaolin products.