采用热分析(TG-DSC)、红外光谱(FTIR)和X线衍射(XRD)等手段,考察伊利石在焙烧过程中的晶体结构变化规律;通过焙烧后伊利石在硫酸溶液中的溶解实验,研究伊利石中Al,K和Si焙烧前后的溶出率变化。研究结果表明:焙烧促使伊利石晶体结构中四面体和八面体结构发生调整和变形,从而使八面体中Al元素赋存的化学环境发生变化,溶出活性显著增强,在H2SO4浓度为3 mol/L、温度为95℃、液固比为5/1 mL/g,转速为600 r/min条件下焙烧,Al在等体积的溶出液中,浓度由77.56 mmol/L提高到203.90 mmol/L。
The crystal structure variation of illite in roasting process was investigated with thermal analysis(TG-DSC),infra-red spectrum(FTIR) and X-ray diffraction(XRD),and dissolution behavior of Al,K and Si in roasted illite was studied by dissolution experiments.The results indicate that roasting treatment deforms and adjusts the structural of tetrahedron and octahedron,which weakens the binding force of Al,K and Si and strengthens their dissolution abilities in acid solution.Compared with unroasted illite,Al in roasted illite is easier to be dissolved.Under the dissolving condition of 3 mol/L H2SO4,95 ℃,liquid to solid ratio 5/1 mL/g and stirring speed 600 r/min,Al concentration in dissolved solution increases from 77.56 mmol/L to 203.90 mmol/L.