Abstracts Book - IMRC 2018

• SF3-O008
STUDY OF THE EFFECT OF THE QUANTITY OF Ni ABOUT THE
ACTIVITY IN HYDRODESULFURIZATION IN CATALYSTS Ni-Mo
SUPPORTED IN MIXED OXIDES OF MgO-TiO2
Carlos López Lozano 1 , Acela López Benítez 1 , Alfredo Guevara Lara 1
1 Universidad Autónoma del Estado de Hidalgo, Chemistry Department, Mexico.
Diesel and gasoline with low sulfur concentration require to optimize the
hydrotreating processes with the most active catalysts. The activity of
hydrodesulfurization catalysts depends on correct formation of active NiMoS
sites. This requires that the metals, Mo and Ni, have a correctly interaction
during the impregnation, drying, calcination and sulfidation steps of
preparation. The use of new supports just like: mixed oxides of MgO modified
with TiO 2 could favors the interaction between Ni and Mo. In this work,
NiMo/MgO-TiO 2 catalyst impregnated with a pH=9 solution and with 0.3, 0.4 and
0.5 = Ni/(Ni+Mo) molar ratios were studied. Catalysts were characterized by
Raman and UV-Vis spectroscopies. Dried catalysts shows the existence of
tetrahedral MoO 4 2- , Ni 2+ (Oh), Ni 2+ (OhDis) species and NO 3
-
ion. Calcined solids shows
that the NO 3
-
band disappears, and MoO 4
2-
Ni 2+ Oh, Ni 2+ Oh dis bands are keeped. It
is notice the formation of Ni-MgO spinel in the solids with 0.4 and 0.5 Ni/(Ni+Mo)
molar ratio, being the 0.5 molar ratio the most intense. Catalytic activity was
evaluated in a continuous flow reactor using the dibenzothiophene
hydrodesulfurization reaction. The reaction rate were of the order of 17.4, 10 y
8.1 (x10 -7 molDBTg -1 s -1 ) for the 0.3, 0.4 y 0.5 molar ratios, respectively. Catalytic
results suggest that when the concentration of Ni is increased the catalytic
activity decreases considerably, obtaining lower percentages of conversion of
dibenzothiophene. This is associated with the formation of the Ni-MgO spinel.
Acknowledgment:
The authors gratefully acknowledge for CONACYT program support referenced
No. 256345/CB-2015-01.
Keywords: NiMo/MgO-TiO2 catalysts, hydrodesulfurization, Ni-MgO spinel
Presenting authors email: carlos.lopez.04@hotmail.com