Iteckne (Apr 2016)
Síntesis y caracterización de heteropolioxometalatos tipo anderson de Ni-Mo(w) soportados sobre alúmina: actividad de hidrodesulfuración de tiofeno
Abstract
Alumina supported (NH4)4[NiMo6-xWxO24H6]•5H2O Anderson type heteropolyoxometalates were synthesized by coprecipitation. These solids were used as precursors in the thiophene hydrodesulfurization catalytic at 400 °C. The catalytic precursors were characterized by textural properties (BET specific surface area and, total pore volume and pore diameter distribution), X-ray diffraction (XRD), IR spectroscopy (FTIR) and S analysis (CHON-S). The specific surface area was between 109 and 35 m2/g with total pore volume and pore diameter distribution of 0,11-0,34 cm3/g and 8,9-9,6 nm, respectively. XRD showed the presence of NiWO4, (NH4)4[NiMo6O24H6]•5H2O and WO3. FTIR analysis can be assigned to the characteristic vibrations of Anderson-type structure, due to stretching and bending of the functional groups present. The NiMo6-O/Al precursor was the most active in the HDS, it had a conversion of 72,75% and was even more active than the AERO commercial catalyst. The results of HDS revealed that the catalytic activity increases as follows: NiMo6-O/Al > AERO > NiMo3W3-O/Al > NiW6–O/Al. The catalytic selectivity of precursors and commercial catalyst (AERO) was directed towards the cis-butene.
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