焦磷酸重量法与X线粉末衍射法测定游离二氧化硅的比较

COMPARISON OF PYROPHOSPHORIC ACIDGRAVIMETRY WITH X-RAY POWDER DIFFRACTOMETRY FOR THE DETERMINATION OF FREE SILICA IN BULK SAMPLES FROM MINES AND POTTERY FACTORIES

为了评价焦磷酸重量法与X线粉末衍射法测定游离SiO_2的结果,我们分别用两法对17个金属矿山和9个瓷厂生产环境中的积尘游离SiO_2进行了测定比较。结果表明:焦磷酸法的测定值高于X线粉末衍射法,且差异显著。把经焦磷酸法测定后的样品沉渣作进一步分析,发现沉渣中存在某些难溶物质未能被焦磷酸彻底除掉。建议用焦磷酸法测定金属矿尘和瓷厂积尘游离SiO_2时,有必要对难溶物质作进一步处理,这对提高分析质量,保证结果的真实可靠是十分必要的。

In order to evaluate the methods of pyrophosphoric acid gravimetry and X-ray powder diffractometry.free silica in bulk samples from work environments of 17 metal mines and 9 pottery factories were determined by using both methods simultaneously.The results indicated that the values determined by pyrophosphoric acid gravimetry were slightly higher than those by X-ray powder diffractometry,but they were not significantly different.Fur- ther analysis found that some insoluble materials in bulk dust were not completely removed by pyrophosphoric acid gravimetry.Thus,it is necessary to treat the insoluble materials to improve the reliability and accuracy of it.