Study On The Selective Ring Opening Of Decalin

The cetane number is an important criterion to evaluate the diesel fuels. The stringent environment legislation request high standard of diesel to reduce the vehicle emissions, thus advanced refinery technologies must be implemented to fulfill this limits such as cetane number. However, there is a great level of saturated bicylic compounds in the diesel, and its cetane number is very low. Through the method of hydrocracking, some of the bicyclic compounds can transfer into single-ring compounds or alkanes, thus highly improve the cetane number of diesel.In this paper, we use decalin as model compounds to study the catalytic performance of the microporous Y zeolites and mesoporos Al-MCM-41zeolite on the decalin hydrocracking reaction. The study found that, a higher acid strength of the Y zeolite leads to its higher cleavage activity of decalin molecular than Al-MCM-41zeolite. On this two catalyst, the distribution of ring opening products and ring contraction products is very close, indicating that both catalysts follows the same reaction mechanism.Besides, in contrast to Ir metal sites, we found the hydrogenation and dehydrogenation ability of Pt metal sites is much higher, thus the reaction activity of Pt1.5/USY is higher than that of the Ir1.5/USYIncreasing the metal loading of the USY catalyst through the incipient wetness method, which reducing the amount of acid sites, weaken the catalyst cracking activity. On the Ptl.5/USY catalyst, the ring opening product yields is the highest, while its cracking activity is the lowest. The ring contraction product yields of the three catalysts is very close.Finally, we studied the hydrogenation reaction of decalin and its isomer on the metal sites. When the top of the reaction tube is loading tht Pt1.0/USY catalyst, the bottom filled with Ptl.0/SiO2catalyst, we found that, decalin cannot react on the Pt1/0/SiO2catalyst, which has no BAS. The hydrogenolysis reaction of decalin isomers can occured on the Pt1.0/SiO2catalyst.