弹性石英毛细管和卡尔费休库仑法测定乙烯、丙烯中微量水

Determination of Trace Water in Ethylene or Propylene by Fused Silica Capillary and Karl Fischer Coulometric Method

以弹性石英毛细管作为节流和气化元件,采用卡尔费休库仑法测定聚合级乙烯、丙烯中微量水,方法准确可靠,检测限可达1μg/g,相对标准偏差不大于5%,回收率为94%～110%,并与电容式湿度计的测定结果进行对比,结果吻合。

?Water content in polymerization grade ethylene or propylene was in trace amount.Adsorption of trace water on the surface of sample pipe and quick gasification of sample made determination of it in ethylene or propylene by Karl Fischer method very difficult.Fused silica capillary was used as throttle and gasifier,and Karl Fischer coulometric method was used to determine trace water in ethylene or propylene.Lower limit of detection was 1 mg/kg.Relative standard deviation was not larger than 5%.Recovery of water was 94%～110%.A hygrometer with capacitive sensor was also used in parallel with the coulometric method.Results coincided.