Studies on preparation of supported cobalt-molybdenum nitrides and their catalytic behaviour for pyridine HDN

gamma-Alumina supported bi(mono)metallic transition metal nitrides were prepared respectively with 12-phosphomolybdic acid plus cobalt nitrate(denoted as CoMoN- I and CoMoN- II related with the precursor of the nitride, CoMoN- I, calcined at 773 K for 6 h before nitriding), ammonium heptamolybdate plus cobalt nitrate(denoted as CoMoN-III), and only ammonium heptamolybdate (denoted as MoN-IV) as the precursor active phases, using temperature programmed reduction with NH3, and characterized with BET, XRD, XPS, H-2-TPD and Raman. Pyridine was selected as a model substrate in order to evaluate the HDN catalytic activity of nitrides synthesized above, It was found that CoMoN- I possesses conspicuously high pyridine HDN activity as compared to that of CoMoN- II, CoMoN- III and MoN-IV.