M. Zdrazil, PREPARATION OF ALUMINA-SUPPORTED MOLYBDENA CATALYSTS BY NEW SLURRY IMPREGNATION METHOD - MOO3 AL2O3 SULFIDE HYDRODESULFURIZATION CATALYST/, Catalysis letters, 27(3-4), 1994, pp. 337-344
A new slurry impregnation method (SIM) of the preparation of a catalys
t or catalyst precursor MoO3/Al2O3 is described. Aqueous slurry of pow
dered MoO3 is mixed with alumina extrudates and the mixture is refluxe
d. A low solubility of MoO3 is sufficient for transport of MoO3 from p
owder form via solution to the surface of the support. The catalysts w
ere tested by hydrodesulfurization of thiophene at 1.6 MPa and 280-400
-degrees-C. Their activity was similar to the activity of industrial a
nd laboratory MoO3/Al2O3 samples prepared by conventional impregnation
with solution of ammonium heptamolybdate. The advantage of the SIM me
thod is that calcination, producing nitrogeneous waste gases, is not r
equired and that all deposited molybdenum species are adsorbed and not
precipitated.