| Hydroprocessing catalysis has been and will continue to be an active research area in the coming years. The key drivers are the tightening environmental regulations, dwindling supply of high quality crude oils, and growing demands for transportation fuels and lubes.(NH4)2MoS4,the precursor,was prepared by ammonium molybdate, aqueous ammonia and ammonium sulfide solution. Use NiCl2·6H2O, FeCl2·4H2O, CrCl3·6H2O as materials and ethanediamine/diethylenetriamine(dien) as chelate to produce Ni(en)3MoS4, Fe(en)3MoS4, Cr(en)3(MoS4)i.5/[Ni(dien)2MoS4, Fe(dien)2MoS4, Cr(dien)2MoS1.5] which are all promoted precursors. Take Fe(dien)2MoS4 for example, the compound is formed as precipitate from the following reaction: Fe(H2NCH2CH2NHCH2CH2NH2)22++ MoS42-→Fe(H2NCH2CH2NHCH2CH2NH2)2MoS4↓Prior to use, the former four precursor compounds was thermally decomposed in atomsphere for about 3 hours when the temperature is 325℃and the pressure is about 1Mpa. This was done in a separate downflow fixed-bed reactor. After that the four catalysts will be formed, named A, A(Ni), A(Fe), A(Cr) or B(Ni), B(Fe), B(Cr) respectively. Use 1% PA-ethanol solution as material to test HDA activities of the four catalysts. The reaction condition is 150℃and 1 Mpa.The results show unsupported A, A(Ni), A(Fe) catalysts have HDA activity. Their products all contains:ethylbenzene, styrene and benzene. Under the action of A and A(Ni), PA generates only three products. But, A(Fe) provide one more product, toluene. Under the action of A(Cr) there are two kinds of products:styrene and ethylbenzene.But the conversion is very low.The results show both A(Ni) and A(Fe) promoted catalysts have higher HDA activity than A catalyst. For they have higher PA conversions and higher ethylbenzene selectivities. A(Fe) catalyst has a better HDA activity than A(Ni) catalyst. A(Cr) has bit HDA activity.A, A(Ni), A(Fe), A(Cr) have no HDA activity about benzene ring. B(Ni), B(Fe), B(Cr) have bit HDA acticity.
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