基于气液态等质量响应化学发光法质量控制轻质烯烃中总氮

Quality control of total nitrogen in light olefins by chemiluminescence method based on gas-liquid equal mass response

基于气液态等质量响应以液体分段标准曲线方程定量不同氮形态和基体的气液态试样,分析了不同基体和相态条件下氮的反应行为。实验结果表明,乙腈气体标准试样(基体90%(φ)氮气+10%(φ)丙烯)及乙腈液体标准试样(基体1,3-丁二烯)、NO(基体氦气)及NO(基体乙烯)气体标准试样的回收率分别为95.6%~98.8%,90.4%~93.5%,93.9%~98.3%,96.1%~102.6%,氮的响应几乎不受氮形态及试样基体和相态变化的影响。氮在乙烯、丙烯和丁二烯中的最低检出限(信噪比(S/N)3)分别为0.06,0.04,0.03 mg/kg;最低检测含量(S/N为10)分别为0.2,0.1,0.1 mg/kg。该技术能够满足不同浓度范围试样的测定需求,对提高工业轻质烯烃产品质量具有重要意义。

Based on the gas-liquid equal mass response,the gas or liquid samples with different nitrogen speciation and matrices were quantified by the liquid segmented standard curve equation,and the reaction behavior of nitrogen under different matrices and phases was systematically analyzed.The experimental results show that the recovery of acetonitrile gas standard sample(90%(φ)matrix N_(2)+10%(φ)propylene),acetonitrile liquid standard sample(matrix of 1,3-butadiene),NO(matrix of He)and NO(matrix of ethylene)gas standard samples is 95.6%-98.8%,90.4%-93.5%,93.9%-98.3%,96.1%-102.6%,respectively.The response of nitrogen is scarcely influenced by the changes of nitrogen speciation and the matrix or phase of the sample.The limits of detection(S/N=3)for nitrogen in ethylene,propylene and butadiene are 0.06,0.04,0.03 mg/kg,respectively,and the limits of quantitative detection(S/N=10)are 0.2,0.1,0.1 mg/kg,respectively.This technology can meet the determination requirements of samples in different concentration ranges,which holds significant importance for improving the quality of industrial light olefin products.