In
the
process
of
biomass
chemical
looping
gasification
using
calcium
ferrite
as
an
oxygen
carrier,
H2O
or
CO2
can
be
injected
into
oxidation
reactor
to
produce
H2
CO
with
high
purity
while
oxidizing
reduced
which
is
a
new
technology
that
has
attracted
wide
attention
in
recent
years.
However,
splitting
reaction
mechanism
still
unclear.
Therefore,
based
on
density
functional
theory
(DFT)
calculations,
adsorption
behavior
and
CO2,
electronic
structure,
path
surface
CaFe2O4
were
systematically
studied
deeply
understand
mechanism.
The
results
show
form
stable
complexes
CaO(111)/Fe(110)
by
chemisorption.
splitted
adsorbed
O*
through
two-step
reaction.
this
process,
step
cracking
HO*
H*
rate-determining
step.
CO*
one-step
reaction,
desorption
from
total
charges
after
are
–0.743
|e|
–0.954
|e|,
respectively,
Fe
atoms
0.931
0.433
respectively.
electron
acceptors,
donors.
carriers
generally
exothermic
reactions,
realize
carrier
provide
heat
for
system.
Energies,
Journal Year:
2025,
Volume and Issue:
18(2), P. 414 - 414
Published: Jan. 18, 2025
Apparent
kinetics
is
often
used
to
describe
a
variety
of
reactions
in
the
field
chemical
looping
and
solar
thermochemical
processes,
yet
rigorous
analytical
methodology
for
utilizing
such
has
been
lacking.
The
implementation
novel
approach
was
exemplified
ceria
cycle
producing
hydrogen,
specifically
H2O-driven
oxidation
step.
H2
production
rate
equation
derived,
rearranging
apparent
from
experimental
data
literature
into
more
suitable
form.
1D
model
integrates
heat
transfer,
fluid
dynamics,
redox
chemistry,
providing
description
directly
irradiated
receiver–reactor.
Model
robustness
ensured
through
oxygen
mass
balance
across
cycle,
comparison
against
shows
high
agreement.
can
be
useful
simulating
cycles
using
any
nonstoichiometric
oxide,
as
ceria-based
oxides
and,
most
importantly,
oxidation-limited
perovskites,
which
optimizing
step
terms
flow,
kinetics,
reaction
times
crucial.
proposed
applied
arbitrarily
complex
reactor
geometries.
inherently
local
nature
also
allows
spatial
distributions
material’s
conversion
utilization
obtained,
paving
way
optimization
strategies
reactor’s
design
operation.
International Journal of Hydrogen Energy,
Journal Year:
2023,
Volume and Issue:
51, P. 834 - 845
Published: Sept. 16, 2023
Hydrogen
is
the
ideal
energy
vector
to
reduce
our
fossil-fuels
dependency
and
diminish
climate
change
consequence.
However,
current
production
still
methane
based.
It
possible
produce
hydrogen
using
bioethanol
from
alcoholic
fermentation
of
organic
waste
by
chemical
looping
processes,
but
unfortunately
redox
systems
generate
with
significant
traces
CO.
In
case
proton
exchange
membrane
fuel
cells
(PEMFC),
must
be
highly
purified
electricity.
Here,
high
porosity
interconnected
Fe2O3
foams
doped
2
wt%
Al2O3
were
manufactured
freeze-casting
method,
obtaining
around
5.1
mmolH2·gsample−1
pure
(<10
ppm
CO)
consuming
only
3.42
mmol
ethanol
on
each
cycles,
no
deactivation.
This
result
shows
possibility
an
abundant
inexpensive
raw
material
as
iron
oxide
scale-up
direct
H2
facilitates
its
use
in
automotive
sector.
