Application of Ethylene Tar as an Additive in Visbreaking of Petroleum Vacuum Residue

The byproduct of ethylene tar has a high content of mono-, bi-, and polycyclic aromatic compounds, as well as cycloalkenes, including aromatic cycloalkenes. This paper evaluates the prospects of using ethylene tar as an additive in the visbreaking process of vacuum residue. A series of experiments on visbreaking of vacuum residue with additives of various refinery streams and ethylene tar were performed in a laboratory flow reactor. As a result of a comparative study of the composition of vacuum residue visbreaking products by different methods, it was shown that the use of ethylene tar compared with kerosene, light cycle oil, and heavy cycle oil allows an increased yield of the target product with a higher proportion of aromatic hydrocarbons. A comparative analysis of the characteristics of asphaltenes and resins of visbreaking products indicates a general trend of changes in the process of visbreaking vacuum residue with refinery streams and ethylene tar. A comparison of the colloidal instability index showed that the use of ethylene tar allows attainment of a more stable visbreaking product concerning refinery streams as additives.