氧弹燃烧-离子色谱法测定原油中氯和溴

IC Determination of Chlorine and Bromine in Crude Oil with Sample Treatment by Combustion with Oxygen Bomb

摘要: 采用氧弹燃烧法对原油样品进行燃烧,然后用碳酸钠-碳酸氢钠溶液作为吸收液进行吸收,并提出了离子色谱法分离测定原油中氯和溴的含量的方法。以Dionex IonPac AS23型分离柱为离子交换柱,以4.8 mmol·L-1碳酸钠-1.0 mmol·L-1碳酸氢钠溶液为淋洗液等度洗脱。氯和溴的质量浓度均在0.01~1 mg·L-1范围内与其峰面积呈线性关系,方法的检出限(3S/N)分别为0.3 mg·kg-1与0.7 mg·kg-1。方法用于原油样品分析,测定值的相对标准偏差(n=6)在3.5%~4.2%之间,回收率在91.8%~109%之间。

Abstract: The sample of crude oil was combusted in oxygen bomb and the chlorine and bromine were absorbed in Na2CO3-NaHCO3 solution. The contents of chlorine and bromine in the solution were determined by IC. The Dionex IonPac AS23 column was used as ion exchange column, and a mixture of 4.8 mmol·L-1 Na2CO3 and 1.0 mmol·L-1 NaHCO3 was used as eluent. Linear relationships between values of peak area and mass concentration of chlorine and bromine were obtained in the same range of 0.01-1 mg·L-1, and values of detection limit (3S/N) found were 0.3 mg·kg-1 for chlorine and 0.7 mg·kg-1 for bromine. The proposed method was applied to the analysis of sample of crude oil, giving values of RSD′s (n=6) and recovery in the ranges of 3.5%-4.2% and 91.8%-109% respectively.