(100b) Selective Ring Opening of Diesel Fuels

The upgrading of diesel fuels with low cetane and high density such as light cycle oil into ultra-low sulphur diesel will gain interest as stricter specifications are introduced. Selective ring opening (RIO) reactions are theoretically ideal for providing cetane and density improvement using a minimum amount of hydrogen. So far, however, the yields of RIO products reported in the literature have been very low. Dominant side reactions such as hydrocracking and n-paraffin isomerisation will lower the diesel yield and cetane number, respectively. For real feed tests the evaluation of experiments is hampered by the lack of good tools for analysis of the hydrocarbon class distribution in the diesel range. Real feed results interpreted as RIO may in fact be a combination of hydrodearomatisation and mild hydrocracking reactions. In order to determine whether a selective ring opening process can be developed, we have tried to optimize the hydrotreating of each hydrocarbon class using catalysts selected by model feed evaluation.