Abstract
Shale oil is characterized by high nitrogen content, coal liquefaction product by high oxygen content and tar sand bitumen by high sulfur content. Shale oil contains a low content of hydrogens bound to aromatic carbons (Ha) and a high content of hydrogens bound to aliphatic carbons β or further from aromatic rings (Ho). The aromaticity is low, and the size of aromatic rings in the structural unit is small (1ring).
The hydrogen content of hydrotreated shale oil increases, and the atomic ratio H/C reaches 2.1. On the other hand, the nitrogen content decreases up to 22-56% of raw shale oil, and the oxygen content up to 25-88% of raw shale oil. During hydrotreatment, Ha and hydrogens bound to aliphatic carbons α from aromatic rings (Hα) decreases, and Ho increases. The resin component decreases remarkably, the aromatic component increases initially and then decreases, and the saturate component increases remarkably. Consequently, the hydroconversion of shale oil is considered to proceed as follows;
Resins→Aromatics→Saturates
The middle fraction (200-325°C) decreases and the naphtha fraction (IBP-200°C) increases. The yield of naphtha fraction is ca.40wt% independent of reaction conditions.
