Desorption and Ionization of Heavy Petroleum Molecules and Measurement of Molecular Weight Distributions
Desorption and Ionization of Heavy Petroleum Molecules and Measurement of Molecular Weight Distributions
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DOI：
10.1021/ef060360t
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发表时间：
2007-01
期刊：
影响因子：
5.3
通讯作者：
K. Qian;K. Edwards;M. Siskin;W. N. Olmstead;Anthony S Mennito;and Gary J. Dechert;Norman E. Hoosain
中科院分区：
文献类型：
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作者：
K. Qian;K. Edwards;M. Siskin;W. N. Olmstead;Anthony S Mennito;and Gary J. Dechert;Norman E. Hoosain
研究了用现场解吸（FD）电离法测定重质石油、真空渣油及其衍生沥青质的分子量分布。研究了碳氢化合物聚合物、重质石油蒸馏切屑以及重质石油的化学组分和溶解度组分，以确定电离效率。FD显示了具有不同化学成分（饱和烃与芳烃）和溶解度（maltene与沥青烯）性质的宽分子量（300 - 5000 Da）分子的有效电离。对电喷雾电离（ESI）进行了探讨，并与FD进行了比较。以往的研究表明，ESI对极性分子（主要是碱性和酸性分子）的电离具有选择性，而FD是一种更普遍的电离方法。比较表明这两种技术基本一致。极性和非极性分子的分子量分布变化不大。ESI产生较低的平均分子量。区别在于……
Field desorption (FD) ionization is studied for the measurement of the molecular weight distribution of heavy petroleum, vacuum residua, and asphaltene derived from them. Hydrocarbon polymers, heavy petroleum distillation cuts, and chemical and solubility fractions of heavy petroleums were examined to determine the ionization efficiency. FD showed effective ionization of molecules of a wide molecular weight range (300−5000 Da) with different chemical compositions (saturates versus aromatics) and solubility (maltene versus asphaltene) properties. Electrospray ionization (ESI) was explored and compared with FD. Previous studies had shown that ESI is selective toward the ionization of polar molecules (mostly basic and acidic molecules) while FD is a more universal ionization method. The comparison revealed general agreement between the two techniques. Small variation in the molecular weight distribution of polar and nonpolar molecules was observed. ESI yields lower average molecular weights. The difference i...