Estimates of the conventional proven hydrocarbon reserves show a tendency toward depletion, and in the near future they will be insufficient to meet the ever-growing global energy demand. The problem of crude oil deficiency can be solved by involving unconventional hydrocarbon resources in both recovery and refinery. However, the hydrogen deficiency of heavy oil and natural bitumen requires technical and technological solutions. Therefore, the hydrogen-donating capacity of water and solvents, particularly in reservoir conditions, is very attractive. In this paper, we study the hydrogen-donating capacity of naphthenic and polar solvents during hydrothermal treatment of heavy oil from Ashal’cha reservoir (Republic of Tatarstan, Russia). It was established that naphthenic solvents significantly influence the viscosity reduction due to the destructive hydrogenation of resins and asphaltenes. Among naphthenic solvents, decalin significantly increases the amount of evolved gases, particularly C₄–C₁₀ isomers and aromatics. However, the maximum evolved gases among all of the used solvents correspond to formic acid. The results of elemental analysis revealed that the H/C ratio rises in crude oil samples after hydrothermal treatment in the presence of cyclohexane and decalin. FT-IR spectral indices revealed an increase in crude oil aliphaticity in case of using solvents from the cyclohexane–tetralin–decalin series due to the cleavage of carbon–heteroatom bonds in aliphatic substitutes of resins and asphaltenes. Significant changes in the FT-IR spectra of crude oil are observed in the presence of tetralin.

中文翻译：

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环烷烃和极性溶剂对重油水热解产物组成和结构的影响

对常规已探明油气储量的估计显示出枯竭趋势，在不久的将来，它们将不足以满足不断增长的全球能源需求。原油短缺的问题可以通过在采收和炼油中引入非常规油气资源来解决。然而，重油和天然沥青的缺氢需要技术和工艺解决方案。因此，水和溶剂的供氢能力，特别是在储层条件下，非常有吸引力。在本文中，我们研究了对来自俄罗斯鞑靼斯坦共和国的 Ashal'cha 油藏稠油进行水热处理过程中环烷烃和极性溶剂的供氢能力。由于树脂和沥青质的破坏性氢化，环烷溶剂显着影响粘度降低。在环烷溶剂中，十氢化萘显着增加逸出气体的量，尤其是 C₄ –C ₁₀异构体和芳烃。然而，在所有使用的溶剂中释放出的最大气体对应于甲酸。元素分析结果表明，在环己烷和萘烷存在下水热处理后原油样品的H/C比升高。FT-IR 光谱指数显示，在使用环己烷-萘满-萘烷系列溶剂的情况下，由于树脂和沥青质的脂肪族替代品中的碳-杂原子键断裂，原油脂肪性增加。在四氢化萘存在下观察到原油 FT-IR 光谱的显着变化。