绢云母的焙烧提钾实验研究

以CaCl2、CaSO4、CaCO3、NaCl和NaOH为助熔剂对四川地区的绢云母矿进行了焙烧提钾试验,结果表明:助剂CaCl2、NaCl及NaOH用量与绢云母矿质量比为0.3∶1时,钾的浸出率分别高达45.46％、54.51％和66.70％；以CaCl2为助剂,进一步研究焙烧温度、添加剂用量、焙烧时间以及矿粉粒度等条件对提钾效果的影响,并通过正交实验确定了最佳提钾条件:绢云母矿粉与助剂质量比为1∶1.2,焙烧温度为900℃,焙烧时间为40 min.在最佳条件下焙烧后,熟料经过水浸,钾的浸出率为81.86％.通过对焙烧前后样品及水浸后的不溶物的XRD分析,初步确定了焙烧过程中的主要物相变化及反应机理.

Study on extracting potassium from sericite by roasting

Using CaCl2,CaSO4,CaCO3,NaCl and NaOH as fluxing additives,extraction of potassium from sericite from Sichuan province by roasting were carried out.The results showed that the potassium leaching rate reached 45.46%,54.51% and 66.70% with the mass ratio of additives(CaCl2,NaCl and NaOH) to sericite being 0.3∶1.With CaCl2 as fluxing additive,the effects of roasting temperature,dosage of additives,roasting time and size of sericite on the extraction of potassium were examined,and the optimal technological parameters were determined by means of orthogonal experiments.The optimal operation conditions were as follows: m(sericite)∶m(CaCl2)=1∶1.2,the roasting temperature at 900 ℃,roasting time of 40 min.Under the optimal conditions,potassium leaching rate reached 81.86%.XRD was used to determine the phase compositions of the samples before and after roasting and water insoluble substance after extracting potassium.The reaction mechanism of extracting potassium was given in this paper.