INVESTIGADORES
AMADEO Norma Elvira
congresos y reuniones científicas
Título:
Ethanol steam reforming Ni(II) Al(III) using layered double hidroxide as catalyst precursor. Kinetic study.
Autor/es:
VERÓNICA MAS; PABLO ARENA; GRACIELA BARONETTI; NORMA AMADEO; MIGUEL LABORDE
Lugar:
Bilbao- España
Reunión:
Simposio; Chemical Reactor Engineering XI. Green Chemical Reactor Engineering; 2007
Resumen:
The kinetic of ethanol steam reforming reaction
using Ni(II)-Al(III) layered double hydroxide (LDH) as catalyst precursor is
studied. The carbonate form of Ni(II)-Al(III) LDH (Takovite) was prepared using
a homogeneous alkalinization procedure. The experiments were performed in a
laboratory fixed bed reactor; since ethanol conversion rate is very fast, previous
experiments were carried out in order to determine the experimental conditions
free from external and internal diffusional resistances. The kinetics
parameters were obtained using the integral reactor model. The ethanol reforming reaction can
be represented as: C2H5OH + 3 H2O = 2 CO2
+ 6 H2. Nevertheless, several reactions can occur and different
products such as methane, acetaldehyde and ethylene can be produced depending on
catalyst and operating conditions. Previous studies based on experimental
evidence demonstrated that methane steam reforming reactions determine the
products distribution, and then the following reaction scheme was used:
C2H5OH = CH4 +
CO + H2
C2H5OH +H2O=
CH4 + CO2 + 2H2
CH4 + H2O = CO
+ 3 H2
CH4 + 2 H2O = CO2
+ 4 H2
The H2 yield for ethanol steam
reforming using the reduced LDH sample reaches values of 5 mol of H2
per mol of ethanol fed. The others products obtained during steady state
conditions operating between 823 and 923 K, are CO, CO2 and CH4.
It is found that the reaction order respect to ethanol is lower than 1. It is
verified that, for each reaction temperature, there is a water/ethanol molar
ratio at which ethanol conversion has a maximum. This means that a competition
between both reactants adsorbed on the same active site is verified.