Asphaltene aggregate is a supramolecular structure in heavy oil,and its hydro-deconstruction is crucial for heavy oil upgrading.The degree of deconstruction of asphaltene nanoaggregates and the change law of average molecular structure of asphaltenes were investigated by using n-heptane to separate the asphaltenes of heavy oils before and after hydro-upgrading of the paraffin-based Huabei heavy oil and intermediate-based Basrah heavy oil.Results show that due to the influence of asphaltene supramolecular structures conversion performance,the removal rates of metals(Ni and V),carbon residue,nitrogen and sulfur in Huabei heavy oil are 14.6,18.7,8.8 and 1.1 percentage points lower than those in Basrah heavy oil,respectively;the conversion rate of asphaltene nanoaggregates in Huabei heavy oil is 8.34 percentage points lower than that in Basrah heavy oil,which is attributed to the spatial hindrance caused by alkyl side chains in the unit layers;the increment amplitude of asphaltene condensation degree in Huabei heavy oil is 5.4 percentage points higher than that in Basrah heavy oil during hydrogenation,which is attributed to the efficiency of saturating polycyclic aromatic hydrocarbons and removing heteroatoms in the unit layers.Therefore,the concentration degree of impurities in the secondary asphaltene of Huabei heavy oil is higher.
关键词
重油/加氢/沥青质/解构/平均分子结构/超分子缔合体/杂质脱除率
Key words
heavy oil/hydrogenation/asphaltene/deconstruction/average molecule structure/supramolecular aggregate/impurity removal rate
维普
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