Hydrotreatment of Middle Distillate from Mongolian Coal Tars

Middle distillates of Mongolian coal tars were hydrotreated to obtain a clean feed for diesel fuel. Elemental and chemical compositions of the tars, distillates and hydrotreated oils were examined qualitatively and quantitatively. The results of hydrotreating tests carried out under hydrogen pressure of 6 MPa, at temperature 350-370 degrees C and for 2 h, showed that hydrodesulfurization proceeded deeply and the activities were over 80%. But the hydrodenitrogenations were low around 50% and the hydrodeoxygenations were below 40% for the distillates. HDS proceeded deeply during hydrotreating of all MDs and the activities were over 80%. Based on the elemental analysis, the HDO activities of MDs were very low compared with HDN and HDS and the temperature increase had a low effect. It can be concluded that reactivity of these MDs can be expressed as HDS >> HDN > HDO. The result showed the nitrogen and oxygen contents of the KhT-MD and BG-MD are also still very high compared with the acceptable level for diesel fuels.

Automated summary

In this study, hydrotreatment of middle distillates of Mongolian coal tars was conducted to obtain a clean feed for diesel fuel. The results showed that hydrodesulfurization proceeded deeply with activities over 80%, while hydrodenitrogenations and hydrodeoxygenations had lower activities. Based on elemental analysis, the HDO activities of middle distillates were very low.