氢键作用对沥青质超分子聚集的影响

对沥青质进行羧基化、磺化和甲基化反应,从加强与钝化氢键作用两个方面对比研究了不同化学处理对沥青质结构、热稳定性以及沥青质聚集的影响.研究发现:羧基、磺酸基等基团引入沥青质分子后,提高了沥青质分子的极性,增强了分子间的氢键作用,显著促进了沥青质的聚集,并且引入的基团极性越强,促进聚集效果越明显;相反,沥青质中含活泼氢官能...

Effects of Hydrogen Bonding Interactions on Asphaltene Supramolecular Aggregation

 The asphaltenesare prone to aggregate and precipitate due to the fused aromatic ringstructures with heteroatom functional groups, which leads to a series ofproblems in the processing and utilization of the heavy oil. However, there isno clear understanding on the intermolecular interaction forces during theasphaltene aggregation process, especially, the role of active hydrogen. Forthis vein, the carboxylation, methylation and sulfonation reactions werefirstly conducted, and the effects of strengthening and weakening hydrogenbonding interactions on asphaltene structure, aggregation and thermal stabilitywere compared. The results show that the introduction of carboxyl and sulfonicgroup enhances the polarity of asphaltene molecule and strengthens theintermolecular hydrogen bonding interactions, which promotes the asphaltene aggregation.Particularly, the stronger the polarity of the functional groups, the moreobvious effects of promoting aggregation. In contrast, after the functionalgroups containing active hydrogen are methylated, the introduction of methylgroup shielded the functional groups forming hydrogen bonding interactions,weakening the hydrogen bonds between the asphaltene molecules, therebyinhibiting the aggregation of asphaltene. The experimental results clearlydemonstrate that the impact of hydrogen bonding interactions on the forming ofasphaltene supramolecular aggregation and reveal the mechanism of methylation,carboxylation and sulfonation affecting asphaltene aggregation.