微波消解-原子荧光光谱法测定硫磺中微量砷的不确定度评定  

Evaluating uncertainty of determining trace As in sulfur by microwave digestion and atomic fluorescence spectrometry

作　　者：涂振权 汪玉洁 欧阳清华 鲁春 Tu Zhenquan;Wang Yujie;Ouyang Qinghua;Lu Chun(Research Institute of Natural Gas Technology,PetroChina Southwest Oil&Gasfield Company,Chengdu,Sichuan,China;Key Laboratory of Natural Gas Quality Control and Energy Measurement,CNPC,Chengdu,Sichuan,China)

机构地区：[1]中国石油西南油气田公司天然气研究院 [2]中国石油天然气质量控制和能量计量重点实验室

出　　处：《石油与天然气化工》2020年第1期98-103,111,共7页Chemical engineering of oil & gas

基　　金：中国石油西南油气田公司科研项目“硫磺中微量铁、砷含量测定方法推广应用”(20180308-05)

摘　　要：采用微波消解和微波赶酸处理样品,通过氢化物-原子荧光光谱法对天然气处理厂产出硫磺中微量砷进行测定。基于建立的有效数学模型,开发了微波消解-原子荧光光谱法测定硫磺中微量砷的不确定度评定方法。结果表明:天然气处理厂产出硫磺中砷含量均小于1μg/g,达到工业硫磺GB/T 2449.1-2014规定的优级品的要求;消解回收率、标准曲线拟合和测量重复性是影响微波消解-原子荧光光谱法不确定度的主要因素,其中对高、中浓度段不确定度贡献最大是消解回收率,而对低浓度段不确定度贡献最大的是标准曲线拟合。Trace As in sulfur produced from the natural gas processing plant was detected by hydride-atomic fluorescence spectrometry after treating with microwave digestion and acid-driving.Based on the established effective mathematical model,an uncertainty evaluation method for determining trace As in sulfur by microwave digestion and atomic fluorescence spectrometry was developed.The results show that all the contents of As in sulfur are lower than 1μg/g,meeting the superior-quality requirement of industrial sulphur of China national standard GB/T 2449.1-2014.The main factors for affecting the uncertainty of this method are the digestion recovery rate,standard curve fitting and measurement repeatability,of which the greatest contribution of the uncertainty with regard to the high and medium concentrations is the digestion recovery rate while that is the standard curve fitting for the low concentration.

关 键 词：不确定度 砷 硫磺 微波消解 原子荧光光谱法 

分 类 号：O657.31[理学—分析化学] TQ125.11[理学—化学]