二次熔矿方式电感耦合等离子体发射光谱法测定棕刚玉中硅铁钛钙镁锆

根据棕刚玉难熔的特点,采用二次熔矿方式对样品进行分解,经盐酸酸化的浸提液用电感耦合等离子体发射光谱法测定硅、铁、钛、钙、镁、锆的含量。第一次加入硼酸-碳酸钠(质量比2∶1)熔矿,熔剂中大量硼酸的存在可以确保棕刚玉样品无需研磨而分解完全;但所得熔融物极难提取,通过提高熔剂中碳酸钠的比例后进行第二次熔矿,使熔融物酸化浸取变得快速简单。对硼酸-碳酸钠混合溶剂的比例、熔矿温度和时间、称样量和样品粒度等实验条件进行优化,分析结果表明方法检出限为0.0003%～0.0051%,精密度(RSD,n=11)为0.88%～4.78%。用标准物质验证,测定值与标准值相符;与国标法对比验证,测定结果相符。该方法样品分解充分,对样品的粒度适应范围宽,可满足生产控制快速检测的要求。

Simultaneous Quantification Measurement of Si, Fe, Ti, Ca, Mg, Zr in Corundum by Inductively Coupled Plasma-Atomic Emission Spectrometry with Secondary-Melting Method

Due to the refractory feature of corundum,secondary melting was adopted to decompose samples.The solution was then lixiviated by HCl and subsequently measured by Inductively Coupled Plasma-Atomic Emission Spectrometry(ICP-AES) to determine the contents of silicon,iron,titanium,calcium,magnesium and zirconium.Boracic acid-sodium carbonate(mass ratio=2∶1) was added as the fluxing agent.The large amount of boracic acid in the flux can completely decompose corundum without grinding.However,it is difficult to dissolve the smelts.Therefore,the solution was to increase the proportion of sodium carbonate in the flux so that the smelts dissolve quickly and simply.The experimental conditions of proportion of boracic acid-sodium carbonate flux,melting temperature and time,sample content,sample grain size and so on were optimized.The results indicate that the detection limit of the method is 0.0003%-0.0051% and the precision(RSD,n=11) is 0.88%-4.78%.The consistent results were verified by standard materials and the national standard method.For this method,the samples were decomposed sufficiently.The grain size accommodation limit of the samples easily meets the requirement for quick inspection.