Characterization and HDS Activity of Cobalt Molybdenum Nitrides

The characterization of cobalt molybdenum nitrides with various cobalt contents has been studied using XRD, TEM, XPS, and temperature-programmed reactions with NH 3 . The hydrodesulfurization of thiophene on the cobalt molybdenum nitride was carried out using a differential microreactor at atmospheric pressure. The XRD analysis of Co(50)973 indicated that Co 3 Mo 3 N was formed from the nitriding of a CoMoO 4 precursor prepared from Co(NO 3 ) 2 ·6H 2 O and (NH 4 ) 6 Mo 7 O 24 ·4H 2 O but not from the mixture of CoO and MoO 3 . Co(10−25)973 had a high surface area of 120−129 m 2 g -1, but Co(50)973 had that of 12 m 2 g -1 . The BET surface area was related to the molybdenum ions (Mo 2+ and Mo 3+ ) and cobalt ion (Co 3+ ) in the bulk sample. The XPS and elemental analyses of Co(50)973 showed that the bulk composition was Co 3 Mo 3 N·N 0.2 and the surface composition was Co 3 Mo 3 N·N 2 . The cobalt molybdenum nitride Co(0−35)973 was more active than cobalt molybdenum sulfide on basis of catalyst weight in the hydrodesulfurization of thiophene at 623 K.