渣油加氢处理前后沥青质的微观结构研究

Microstructure characterization of asphaltenes from atmospheric residue before and after hydroprocessing

采用元素分析、扫描电镜和透射电镜等分析方法对渣油原料中的沥青质、加氢处理后的沥青质及添加高芳香性轻循环油(LCO)反应后的沥青质进行对比研究。结果发现,渣油加氢处理前后沥青质的表面呈现出光滑表面和多孔的球形颗粒表面两种完全不同的形貌。渣油加氢前后沥青质的芳核堆砌表现出明显的长程无序局部有序的特征;加氢处理后的沥青质芳核片层易于堆砌,出现了多层堆砌、长程有序的类石墨结构。渣油中高芳香性LCO的添加有利于促进沥青质的加氢反应、改善沥青质芳核系统在渣油加氢处理过程中的聚集行为。

A comparative study on microstructure of asphaltenes obtained from an atmospheric residue（AR）,a hydroprocessed oil of AR and a blending of AR with high aromatic light cycle oil（LCO） was carried out by element analysis,scanning and transmission electron microscopy（SEM and TEM）.Different asphaltene morphologies,smooth surface and porous surface with spherical particles,were observed by SEM before and after hydroprocessing.The results of TEM micrographs show that the aromatic ring stacking of original asphaltene is characterized of long range disorder and short range order,and multi-stacking graphite-like carbon with long range order is observed for hydroprocessed asphaltene.The addition of high aromatic LCO into AR enhances the hydrogenation reactions of asphaltene and inhibits the aggregation of aromatic ring systems under AR hydrotreating.