干法灰化法分离环境擦拭样品的优化研究  

Studies on Dry-ashing Method for Isolation of Environmental Wipe Sampling

作　　者：罗立力[1] 杨天丽[1] 刘雪梅[1] 龙开明[1] 汤垒 邵学鹏[1] 

机构地区：[1]中国工程物理研究院核物理与化学研究所,绵阳621900

出　　处：《材料导报》2014年第20期94-98,共5页Materials Reports

摘　　要：通过同步热分析仪和光学显微镜对纯金属铁粉、铅粉以及模拟擦拭样品中的铁粉、铅粉在干法灰化过程的加热行为进行了比较研究,在此基础上对干法灰化法分离进行了优化。实验发现纯金属铁粉的团聚现象随着温度和氧分压升高而加剧。擦拭样品中的铁粉在大气气氛灰化时形貌变化类似纯金属铁粉;而在纯氧气氛中灰化形成了圆珠状铁微粒,灰化温度更高铁粉将与擦拭布共熔黏附在容器底部。铅粉在灰化过程中发生熔融氧化,形成橙色PbO微粒以及黑色高价铅氧化物微粒,微粒圆滑,团聚严重。灰化法分离擦拭样品应选择干燥气氛进行,预分散处理、较低的灰化温度和氧分压均有利于减少团聚现象。The heating behavior of iron powder and lead particles from pure metal or simulated wipe samples in the dry ashing process were studied by simultaneous thermal analysis and optical microscope, on the basis of which dryashing method was optimized. Particle agglomeration increased as the temperature and oxygen partial pressure rised. Iron particles from wipe samples had the similar change of morphology as metal iron particles when ashing in the atmosphere. While in oxygen ball-like particles formed, wipe cloth melted with iron particles and stick to the bottom of the vessel. Lead particles oxidated and melted during ashing, formed ball-like orange PbO paricles and black oxide particles （higher oxidate）,with severe agglomeration. Ashing process should be done in dry environment. Pre-separation, lower oxygen pressure and ahing temperature could effectively reduce agglomeration.

关 键 词：擦拭实验 灰化分离法 团聚 同步热分析 

分 类 号：O652.7[理学—分析化学]