By using pellet sample preparation method,a new analytical method for rapid determination of calcium oxide and silicon dioxide in calcium hydroxide powder by wavelength dispersive X-ray fluorescence spectrometry was established.Because there are no national standard samples,homemade lime powder standard samples were used to draw working curves.The effects of particle size and moisture absorption on analytical results were investigated.The results showed that fluorescence count rate was most stable,when the sample size was 74 μm,pressure prototype pressure was 12 MPa,and pressing time was 45 s.The best result was obtained within 30 minutes.The theoretical coefficient method and the empirical coefficient method were used together to correct the matrix effect.The relative standard deviation of each component(RSD,n=11) was between 0.04% and 0.43%.The results obtained from 5 samples were consistent with those determined by the conventional chemical analysis method.%采用粉末压片法制样,建立了波长色散X射线荧光光谱法快速测定生石灰粉中氧化钙、二氧化硅的分析方法.由于没有国家标准样品,采用自制生石灰粉标准样品绘制工作曲线.考察了样品粒度及吸潮对分析结果的影响.实验表明,在样品粒度为74 μm、压样机压力为12 MPa、压制时间为45 s的制样条件下荧光计数率最稳定,在30 min内测定样品效果最佳.采用α理论系数法和经验系数法相结合校正基体影响.对同一生石灰粉样品进行精密度实验,各组分的相对标准偏差(RSD,n=11)在0.04%~0.43%.测定了5个生石灰粉样品,所得结果与常规化学分析方法测定值相符.
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