摘要
采用改变相比/顶空气相色谱法测定了甲烷、乙炔、乙烯、乙烷和丙烷在变压器油中的分配常数。顶空瓶中的气体样品经石英毛细管送到气相色谱仪的六通进样阀样品管中,然后进行分离和定量。采用标准曲线法定量,通过测定5个不同相比时轻烃组分的顶空浓度,计算顶空浓度倒数与相比之间的线性回归方程,测定了20℃和50℃时烃类气体在变压器油中溶解气体的分配常数。除甲烷外,计算所得的分配常数与文献值基本吻合,油中溶解气体浓度的实验值与实际值之间的相对误差小于4 14%,表明用此方法可以测定不同温度下变压器油中溶解气体的分配常数,为在线气相色谱分析提供基础数据。
The partition coefficients of dissolved gases in transformer oil were determined using a phase ratio variation method and static headspace gas chromatography (GC). A pressure balancing and gas volume-metering device was connected to the vent of a sample loop on a six-port injection valve of the GC. The gas phase sample from the headspace vial of 25 mL was transferred to an 80 μL sample-loop through a fused silica capillary of 0.53 mm i.d., and then separated and determined quantitatively by GC. A 2 m×1 mm i.d. GDX502 micro-packed column was used for the separation. Five different gas-liquid volume ratios in the headspace vials were measured at different equilibrium concentrations. The partition coefficients of hydrocarbon gases including methane, acetylene, ethylene, ethane and propane dissolved in transformer oil were determined by using linear regression analysis at 20 ℃ and 50 ℃ separately. The errors between the real values and regression values from experimental data were less than 4.14% except methane. Fundamental data for on-line measurement of dissolved gases in transformer oil are provided by GC.
出处
《色谱》
CAS
CSCD
北大核心
2004年第3期193-196,共4页
Chinese Journal of Chromatography
基金
科技部科学仪器攻关课题(96 A23 01 05).
关键词
静态顶空气相色谱
相比
分配常数
溶解气体分析
static headspace gas chromatography
phase ratio
partition coefficient
dissolved gas analysis
