辽河超稠油常压渣油热改质前后石油酸的分布与组成结构研究

摘要

采用醇碱法对辽河超稠油热改质前后常压渣油(AR)中的石油酸进行分离提纯,得到两种石油酸(简称为改质前和改质后).采用FTIR、元素分析、负离子ESI FT-ICR MS、13C NMR、1H NMR、化合物DBE及碳数分布等方法对提纯的石油酸进行定性和定量分析.实验结果表明,改质前后的石油酸均以二环、三环、四环、五环或单苯环并单环环烷酸为主,石油酚、芳香酸相对含量较低;没有直接与环相连的羧基在改质过程中易发生脱羧反应,部分解释了热改质AR的蒸发损失低于直馏AR的原因.%Two kinds of petroleum acids were separated through the ethanol-alkali extraction from the Liaohe atmospheric residue(AR) and purified,in which AR firstly was modified by thermal upgrading.The qualitative and quantitative analysis of the petroleum acids were carded out by means of FTIR,element analysis,negative ion ESI FT-ICR MS,13C NMR and 1H NMR.The double bond equivalents(DBE) and carbon number distribution of the petroleum acids were investigated.The results indicated that,the major components in the petroleum acids with and without the thermal upgrading were bicyclo-,tricyclo-,tetracyclo-,pentacyclo-and benzenoid-monocyclo-naphthenic acids with a little petroleum phenols and aromatic acids.During the thermal upgrading,the carboxyls which were not directly connected to the rings were prone to decarboxylation,which partly explained less evaporation loss of AR with the thermal upgrading than that of AR without the thermal upgrading.