原油相对分子质量测定新方法

A new method for determination of relative molecular mass of crude oil

关键词:  原油  相对分子质量  碳数分布  元素分析 

Key words:  crude oil  relative molecular mass  carbon number distribution  element analysis

摘要:

针对辽河油田沈84-安12块高凝油,利用元素分析仪测定原油碳、氢元素含量及氢碳原子个数比,判定原油主要组成。对原油进行气相色谱分析,采用归一化法得到原油碳数分布。结合原油的元素分析和碳数分布,计算出原油的相对分子质量。实验结果:辽河油田沈84-安12块高凝油的碳、氢元素质量分数之和达99.21%,氢碳原子个数比为2.10,说明此原油以饱和烷烃为主；气相色谱测得原油碳数分布为nC₁₂～nC₃₅之间的烃类组分,分离效果好；由碳元素浓度和碳数分布计算所得辽河油田沈84-安12块高凝油相对分子质量为334.98,由氢元素浓度和碳数分布计算所得数值为332.92,两者相差2.06。

Abstract:

The content of C and H in the high pour-point oil of Shen84-An12 Block in Liaohe Oilfield was measured by element analyzer, and then the major components of this oil were analyzed. The oil’s carbon number distribution was obtained by GC. Combining with element analysis and the carbon number distribution, the relative molecular mass of the oil was calculated. The results show that saturated alkane is the major component of this oil because that the contents of C and H reached the sum of 99.21%, and the ratio of hydrogen atom to carbon atom is 2.10; the distribution of carbon number of crude oil is from nC₁₂ to nC₃₅, and the good analysis results about the distribution of the carbon numbers in the oil have been obtained by the chromatography conditions described in the paper; the molecular mass of the high pour-point oil of Shen84-An12 Block in Liaohe Oilfield is 334.98, which was calculated by the content of carbon and the distribution of the carbon numbers. In addition, calculating value is 332.92 by the content of hydrogen and the distribution of the carbon numbers. The difference value is 2.06.