Characterization and HDS activity of cobalt molybdenum nitrides

The characterization of cobalt molybdenum nitrides with various cobalt cont ents has been studied using XRD, TEM, XPS, and temperature-programmed react ions with NH3. The hydrodesulfurization of thiophene on the cobalt molybden um nitride was carried out using a differential microreactor at atmospheric pressure. The XRD analysis of Co(50)973 indicated that CO3Mo3N was formed from the nitriding of a CoMoO4 precursor prepared from Co(NO3)(2). 6H(2)O a nd (NH4)(6)Mo7O24. 4H2O but not from the mixture of CoO and MoO3. 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 ( Mo2+ and Mo3+) and cobalt ion (Co3+) in the bulk sample. The XPS and elemen tal analyses of Co(50)973 showed that the bulk composition was CO3MO3N .N-0 .2 and the surface composition was Co3Mo3N .N-2 The cobalt molybdenum nitri de Co(0-35)973 was more active than cobalt molybdenum sulfide an basis of c atalyst weight in the hydrodesulfurization of thiophene at 623 K.