研究了一种通过水热碱法-酸液回流-煅烧,从含钛电炉熔分渣中分离提取、制备纳米结构六钛酸钾晶须材料的新方法.采用扫描电子显微镜、透射电子显微镜、X射线衍射、X射线荧光光谱等表征手段,详细探讨了煅烧过程中钛钾摩尔比、煅烧温度、保温时间和水浸对最终产物物相和微观形貌的影响.含钛电炉熔分渣在水热温度为200℃,水热反应时间为24 h,碱液浓度达12 mol·L-1时,经酸液回流后所得偏钛酸呈一维单晶纳米棒状结构.随着钛钾摩尔比从1.50增加至1.75,煅烧温度从800℃升高到1100℃,保温时间从0.5 h延长至7 h,制备得到的六钛酸钾晶须的纯度、结晶性及长径比逐渐提高.当钛钾摩尔比为1.75,煅烧温度为1100℃,保温5 h,水浸2 h后可制备得到尺寸均一的六钛酸钾纳米晶须.
Potassium titanate ( K2 Ti6 O13 ) nanowhiskers were successfully prepared from electric furnace molten slag with titanium by a hydrothermal method with alkaline solution, then refluxing in an acid medium and finally calcination. The effects of titanium-to-potassium mole ratio, calcination temperature, reaction time and water immersion on the crystal phase and morphology of as-prepared products during the calcination process were investigated in detail by scanning electron microscopy, transmission electron microscopy, X-ray diffraction and X-ray fluorescence. It is found that one-dimensional single crystalline metatitanic acid nanorods with uniform size are obtained when the hydrothermal reaction is controlled at about 200℃ for 24 h in a 12 mol·L-1 potassium hydroxide solution. The purity, the crystallinity degree and the aspect ratio of formed potassium titanate whiskers are improved with increasing titanium-to-potassium mole ratio from 1.50 to 1.75, calcination temperature from 800 to 1100℃, and reaction time from 0.5 to 7 h. The optimum conditions for preparing potassium titanate nanowhiskers are the titanium-to-potassium mole ratio of 1.75, the calcination tem-perature of 1100℃, the reaction time of 5 h, and the water immersion time of 2 h.