INVESTIGADORES
YORI Juan Carlos
artículos
Título:
Modification of the performance of WO3-ZrO2 catalysts by metal addition in hydrocarbon reactions
Autor/es:
GERARDO C. TORRES; DEBORA L. MANUALE; VIVIANA M. BENÍTEZ; CARLOS R.. VERA; JUAN C. YORI
Revista:
QUÃMICA NOVA
Editorial:
SOC BRASILEIRA QUIMICA
Referencias:
Lugar: Río de Janeiro; Año: 2011
ISSN:
0100-4042
Resumen:
A study of the different hydrocarbon reactions (isomerization of n-butane,
cyclohexane dehydrogenation and hydroisomerization-cracking of n-octane) over WO3-ZrO23-ZrO2
(WZ) catalysts promoted with Ni was performed. The effect of the addition of Ni on the
properties of both the acid and metal functions was assessed by means of temperature
programmed reduction and temperature programmed desorption of pyridine.
A different behavior was seen depending on the Ni content level. At the reactions
conditions used in this test, Ni was found as NiO at low Ni concentration while at high Ni
concentrations a small fraction of the Ni was present as a metal. TPD results indicated that Ni
strongly modified total acidity and the concentration of strong acid sites.
For all the reaction tests, the behavior in reaction of the catalysts may be explained
from the TPD and TPR results. In the cyclohexane dehydrogenation reaction, Ni addition
promotes both benzene (Bz) and methyl cyclopentane (MCP) production. The
hydroconversion activity (n-C4 and n-C8) of the WZ catalysts increases with the augment of
total acidity produced by Ni. Activity was found to be directly related to the amount of
surface acid sites, thus indicating that the rate of these reactions is controlled by the acid
function. It was also found that the selectivity to reaction products is modified according to
the acid strength distribution changes produced by Ni addition.
total acidity produced by Ni. Activity was found to be directly related to the amount of
surface acid sites, thus indicating that the rate of these reactions is controlled by the acid
function. It was also found that the selectivity to reaction products is modified according to
the acid strength distribution changes produced by Ni addition.
total acidity produced by Ni. Activity was found to be directly related to the amount of
surface acid sites, thus indicating that the rate of these reactions is controlled by the acid
function. It was also found that the selectivity to reaction products is modified according to
the acid strength distribution changes produced by Ni addition.
total acidity produced by Ni. Activity was found to be directly related to the amount of
surface acid sites, thus indicating that the rate of these reactions is controlled by the acid
function. It was also found that the selectivity to reaction products is modified according to
the acid strength distribution changes produced by Ni addition.
4 and n-C8) of the WZ catalysts increases with the augment of
total acidity produced by Ni. Activity was found to be directly related to the amount of
surface acid sites, thus indicating that the rate of these reactions is controlled by the acid
function. It was also found that the selectivity to reaction products is modified according to
the acid strength distribution changes produced by Ni addition.
