SHS Membrane for the Dehydrogenation of n-Butanol to Butadienes

Article abstract of DOI:10.1134/S0020168519080181

Abstract—: We have synthesized catalytically active membranes based on α- and γ-Al₂O₃ powders for the dehydration and dehydrogenation of butyl alcohol to butadiene and hydrogen. The open porosity of the samples obtained in this study is 41% in the case of α-Al₂O₃ and 38% in the case of γ-Al₂O₃. The open pore size is 4.6–5.1 μm in the α-Al₂O₃ material and 0.5–0.8 μm in the γ-Al₂O₃ material. We have implemented a hybrid, membrane–catalytic process for the dehydrogenation of butanol by combining reaction and hydrogen separation steps in a single device. It has been demonstrated that the dehydration of n-butanol on a γ-Al₂O₃ converter leads to the formation of a butylene fraction with a selectivity of 99.88–100% at a temperature of 300°C, which is 50°C lower than in the case of commercially available gamma-alumina granules. The dehydrogenation of butylene to butadiene on an α-Al₂O₃ membrane with selective hydrogen removal from the reaction zone has made it possible to raise the 1,3-butadiene output from 16.5 to 22.6 L/(h g_{act. comp.}), with the degree of ultrapure hydrogen extraction reaching ~16%. After the experiment was run for 20 h, no decrease in the catalytic activity of the system was detected, as distinct from commercial solutions, in which a regeneration step is necessary every 8–15 min.

Full text of DOI:10.1134/S0020168519080181

ISSN 0020-1685, Inorganic Materials, 2019, Vol. 55, No. 8, pp. 798–802. © Pleiades Publishing, Ltd., 2019.
Russian Text © The Author(s), 2019, published in Neorganicheskie Materialy, 2019, Vol. 55, No. 8, pp. 846–850.
SHS Membrane for the Dehydrogenation of n-Butanol to Butadienes
V. I. Uvarova, *, M. I. Alymova, V. E. Loryana, V. S. Shustova, A. S. Fedotova, and M. V. Tsodikovb
aMerzhanov Institute of Structural Macrokinetics and Materials Science, Russian Academy of Sciences,
ul. Akademika Osip’yana 8, Chernogolovka, Moscow oblast, 142432 Russia
bTopchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, Leninskii pr. 29, Moscow, 119991 Russia
*e-mail: uvar@ism.ac.ru
Received June 19, 2018; revised March 13, 2019; accepted March 20, 2019
Abstract—We have synthesized catalytically active membranes based on α- and γ-Al2O3 powders for the
dehydration and dehydrogenation of butyl alcohol to butadiene and hydrogen. The open porosity of the sam-
ples obtained in this study is 41% in the case of α-Al2O3 and 38% in the case of γ-Al2O3. The open pore size
is 4.6–5.1 μm in the α-Al2O3 material and 0.5–0.8 μm in the γ-Al2O3 material. We have implemented a
hybrid, membrane–catalytic process for the dehydrogenation of butanol by combining reaction and hydro-
gen separation steps in a single device. It has been demonstrated that the dehydration of n-butanol on a γ-
Al2O3 converter leads to the formation of a butylene fraction with a selectivity of 99.88–100% at a temperature
of 300°C, which is 50°C lower than in the case of commercially available gamma-alumina granules. The
dehydrogenation of butylene to butadiene on an α-Al2O3 membrane with selective hydrogen removal from
the reaction zone has made it possible to raise the 1,3-butadiene output from 16.5 to 22.6 L/(h gact. comp.), with
the degree of ultrapure hydrogen extraction reaching ~16%. After the experiment was run for 20 h, no
decrease in the catalytic activity of the system was detected, as distinct from commercial solutions, in which
a regeneration step is necessary every 8–15 min.
Keywords: ceramics, nanoparticles, dehydration, dehydrogenation, butyl alcohol, butadiene, membrane
DOI: 10.1134/S0020168519080181
INTRODUCTION
ventional fixed-bed catalytic reactors, thus allowing
for more active processes.
Butadiene is a main monomer employed in mod-
ern commercial production of synthetic caoutchouc.
Butadiene is basic to the production of the vast major-
ity of general-purpose synthetic rubbers (cis-1,4-buta-
diene, styrene–butadiene, and butadiene–methylsty-
rene stereoregular rubbers) and a number of special-
purpose synthetic rubbers (nitrile–butadiene, butadi-
ene–methylvinylpyridine, and other rubbers). In
addition, butadiene is utilized on a commercial scale
to manufacture synthetic resins, adipodinitrile, and
cebacic acid [1–7]. Analysis of the literature led
researchers to propose using a hybrid, membrane–
catalytic process for the dehydrogenation of n-butanol
to 1,3-butadiene, a valuable monomer, by combining
in a single device the reaction step, which occurs in
channels of a catalytic converter, and the hydrogen
separation step on a palladium-containing membrane
incorporated into the cavity of a converter. This allows
one to reduce the total energy required for the process
and the dimensions of the apparatus [8–11].
The purpose of this work was to synthesize catalyt-
ically active membranes for the dehydration and dehy-
drogenation of butyl alcohol and the formation of
hydrogen and butadiene, which is basic to the prepa-
ration of synthetic resins, caoutchouc, plastics, chem-
ical fiber, pharmaceuticals, fragrances, and other sub-
stances. To activate the dehydrogenation of butyl alco-
hol to butylene, we attempted to employ γ-Al2O3
membranes having an amorphous structure and large
surface area.
EXPERIMENTAL
To produce catalytically active membranes with
predetermined parameters, we used coarse Elektroko-
rundum γ-Al2O3 powder with a particle size of up to
100 μm. To the starting γ-Al2O3 powder we added
magnesium oxide powder (manufactured at the
Krasnyi Khimik plant, Russian Federation State Stan-
dard GOST 4526-75) and silicon carbide powder (pre-
pared by self-propagating high-temperature synthesis
(SHS)) to give the eutectic composition. In addition,
we prepared a porous γ-Al2O3-based converter. It was
synthesized from aluminum hydroxide, Al(OH)3,
In recent years, there has been great practical inter-
est in studies of gas-phase heterogeneous catalytic
reactions in membranes, which offer considerably bet-
ter mass and heat exchange in comparison with con-
798

SHS MEMBRANE FOR THE DEHYDROGENATION
799
powder with the addition of pseudoboehmite,
AlOOH, gel.
S1
The powders used were examined by scanning
electron microscopy on a LEO 1450 equipped with an
INCA Energy 300 energy dispersive X-ray spectrome-
ter system. Their phase composition was determined
by X-ray diffraction on a DRON-3M diffractometer.
S5
S6
The powders were mixed by ball-milling for 1 h
with Al2O3 grinding media. The powder mixture was
then compacted by single-action pressing, followed by
vacuum sintering.
The open pore size in the synthesized material was
estimated in the capillary displacement model using
the Laplace formula for cylindrical pores. The largest
pore size was determined as
S2
S3
S4
300 μm
Spectrum C, % O, % Al, %
2πRσcos θ = πR²(ΔР – hγg).
Here R is the capillary radius, σ is the surface tension
force, θ is the contact angle, h is the height of the liq-
uid column over the sample surface, γ is the density of
the liquid, g is the acceleration of gravity, and ΔP =
Р∞ – Pg – Pv is the gas phase pressure upon pore for-
mation, where Р∞ is the pressure in the experimental
chamber, Pv is the vapor pressure over the liquid
phase, and Pg is the pressure of gaseous impurities.
The open porosity in the ceramic membranes pro-
duced by us was also measured using a mercury poro-
simeter in accordance with the Russian Federation
State Standard GOST 26849-86.
S1
S2
S3
S4
S5
S6
4
52
43
57
54
52
19
44
57
43
44
48
67
2
14
Fig. 1. Micrograph and X-ray microanalysis data of the
α-Al O powder.
2
3
The specific surface area of the powders and sintered
leaching in a hydrochloric acid solution according to
the reaction scheme SiC + MgO + 2HCl → MgCl2 +
H2O, the synthesized silicon carbide powder was col-
lected on a filter. Figure 2 shows a micrograph of the
silicon carbide powder thus prepared.
samples was measured using a Sorbi-M instrument.
The catalytic dehydration of butanol occurs
according to the following scheme:
BuOHꢀ (n-butylene + cis-butylene
To enhance the strength of the membrane, an orga-
nosilicon binder was added to the starting α-Al2O3
powder.
+ trans-butylene) + Н2О, ΔН = 34 kJ mol.
The process is run in a conventional flow reactor.
As a catalyst, we used a porous γ-Al2O3-based mem-
brane produced by SHS as described above. For the dehy-
drogenation of n-butylene to butadiene, we prepared and
tested granulated model catalysts: α-Al2O3 + K, Ce, Mn
(10%); α-Al2O3 + K, Ce, Mn (5%) + Fe (5%) (sepa-
rate application); and α-Al2O3 + K, Ce, Mn (5%) +
Fe (5%) (joint application).
After mixing in a ball mill, the powders were com-
pacted by single-action pressing at 30–90 MPa, and
the compacts were sintered. At sintering temperatures
in the range from 1100 to 1450°C, a eutectic mixture of
magnesium oxide and silicon carbide powders forms a
liquid phase in the form of clinoenstatite, MgSiO3,
which wets Al2O3 particles to give a robust porous skel-
eton of the membrane. As the temperature is raised,
the organosilicon binder forms a fine-particle sinter-
ing-active SiO2 phase, which reacts with aluminum
oxide and clinoenstatite particles to form mullites
(Mg2Al4Si5O18 indialite and MgAl2O4 spinel). Figure 3
presents an X-ray diffraction pattern of a fracture sur-
face of the samples obtained. There are well-seen
reflections from α-Al2O3, MgAl2O4 spinel, and
Mg2Al4Si5O18 indialite, a mixed oxide with a hexago-
nal structure.
RESULTS AND DISCUSSION
Figure 1 presents a micrograph of the starting α-
Al2O3 powder, together with elemental analysis data
for the powder particles. It is worth noting that the α-
Al2O3 powder contains no significant amounts of any
second-phase inclusions.
The produce the membrane, magnesium oxide and
silicon carbide powders were added to the starting α-
Al2O3 powder to give the eutectic composition. Silicon
carbide was prepared by SHS with a reducing stage by
the reaction SiO2 + Mg + C → SiC + MgO. After
The porous ceramic membrane has the form of a
hollow cylinder 137 mm in total length, with a working
INORGANIC MATERIALS Vol. 55 No. 8 2019

800
UVAROV et al.
MgAl2O4
Mg2Al4Si5O18
α-Al2O3
2000
1500
1000
500
0
1 μm
10
20
30
40
50
60
70
80
2θ, deg
Fig. 2. Micrograph of the starting silicon carbide powder.
Fig. 3. X-ray diffraction pattern of an α-Al O -based sample.
2
3
zone length of 120 mm, outer diameter of 25 mm, and
wall thickness of 7 mm.
A reactor containing the synthesized membranes
was used to carry out the dehydration and dehydroge-
nation of butyl alcohol (n-butanol), a biomass fermen-
tation product, to butadiene and hydrogen.
The calculated open pore size in the synthesized
sample is 5.1–5.3 μm. The open pore size in the
ceramic membranes, measured using a mercury poro-
simeter in accordance with the Russian Federation
State Standard GOST 26849-86, was 4.6–5.1 μm. The
open pore size is an equivalent hydraulic diameter of a
channel in which a fluid (gas or liquid) flows. The
open porosity of the samples, as determined by hydro-
static weighing, was 41%.
It was found that the dehydration of n-butanol on a
γ-Al2O3 converter at 300°C led to the formation of a
butylene fraction with a selectivity of 99.88–100%. It
is worth noting that complete dehydration of n-buta-
S7
In addition, we prepared a porous γ-Al2O3-based
converter. It was synthesized from Al(OH)3 powder
with the addition of pseudoboehmite, AlOOH, gel.
The samples were pressed at 30–90 MPa and then sin-
tered at a temperature of 750°C.
S4
S1
S6
Figure 4 presents a micrograph and elemental anal-
ysis data of the starting aluminum hydroxide powder.
It is worth noting that the starting aluminum hydrox-
ide powder contains no significant amounts of any
second-phase inclusions.
S5
S3
S2
Figure 5 presents a micrograph and elemental anal-
ysis data of a fracture surface of a sample synthesized
using γ-Al2O3. It is seen that the experimental sample
contains no significant amounts of any second-phase
inclusions.
5 μm
Figure 6 shows an X-ray diffraction pattern of the
γ-Al2O3-based sample. There is a well-seen character-
istic peak of amorphous gamma-aluminum oxide at
2θ = 42.4°.
The specific surface area of the starting Al(OH)3
powder was 129.4 1.06 m2/g and that of the sample
after synthesis was 115.9 1.4 m2/g.
The open pore size in the synthesized material was
measured in accordance with the Russian Federation
State Standard GOST 26849-86 and was determined
to be 0.5–0.8 μm.
Spectrum O, % Al, %
S1
S2
S3
S4
S5
S6
S7
64
65
69
68
69
60
70
36
35
31
32
31
40
30
Fig. 4. Electron micrograph and X-ray microanalysis data
of the aluminum hydroxide powder.
INORGANIC MATERIALS
Vol. 55
No. 8
2019

SHS MEMBRANE FOR THE DEHYDROGENATION
801
experiment was run for 20 h, no decrease in the cata-
lytic activity of the system was detected, as distinct
from commercial solutions, in which a regeneration
step is necessary every 8–15 min.
S1
Thus, the use of n-butanol in the preparation of
synthetic caoutchouc can be a further important step
in the development of environmentally friendly chem-
ical plants based on renewable raw materials. Another
potentially attractive approach for addressing this
issue is to employ a hybrid, membrane–catalytic pro-
cess, which makes it possible to reduce the total energy
required for the process by combining in a single
device the reaction step, which occurs in channels of
catalytically active membranes, and the hydrogen sep-
aration step on a palladium-containing membrane
incorporated into the cavity of a converter. This allows
one to considerably reduce the dimensions of the
apparatus, simplify its design, and obtain high-purity
products at the reactor outlet with a higher yield in
comparison with a conventional fixed-bed catalytic
reactor.
S2
S3
50 μm
S4
Spectrum O, % Al, %
S1
S2
S3
S4
56
54
53
49
44
46
47
51
CONCLUSIONS
Fig. 5. Micrograph and X-ray microanalysis data of the
γ-Al O -based powder.
We have synthesized a porous membrane based on
amorphous γ-Al2O3 using aluminum hydroxide pow-
der with the addition of pseudoboehmite, AlOOH,
gel, which were compacted at a pressure in the range
30–90 MPa and sintered at a temperature of 750°C.
It has been demonstrated that the dehydration of
n-butanol on a γ-Al2O3 converter leads to the forma-
tion of a butylene fraction with a selectivity of 99.88–
100% at a temperature of 300°C, which is 50°C lower
than in the case of commercially available gamma-
alumina granules.
The dehydrogenation of butylene to butadiene on
an α-Al2O3 membrane with selective hydrogen removal
from the reaction zone has made it possible to raise the
1,3-butadiene output from 16.5 to 22.6 L/(h gact. comp.),
with the degree of ultrapure hydrogen extraction
reaching ~16%. After the experiment was run for 20 h,
no decrease in the catalytic activity of the system was
detected, as distinct from commercial solutions, in
which a regeneration step is necessary every 8–15 min.
2
3
350
300
250
200
150
100
50
440
311
111
220
400
222
511
0
10
20
30
40
50
60
70
80
2θ, deg
Fig. 6. X-ray diffraction pattern of the γ-Al O -based
2
3
amorphous sample.
FUNDING
This work was supported by the Russian Science Foun-
dation, agreement no. 17-13-01270.
nol on a commercially available γ-Al2O3 is only possi-
ble at 350°C.
For butylene dehydrogenation, a thin-film γ-Al2O3 +
K, Ce, Cr (5%) + Fe (5%) catalyst was applied to an
α-Al2O3 membrane. The dehydrogenation of butylene
to butadiene with selective hydrogen removal from the
reaction zone made it possible to raise the 1,3-butadi-
ene output from 16.5 to 22.6 L/(h gact. comp.), the C4
selectivity to 25.59%, and the degree of ultrapure
hydrogen extraction to ~16%. Note that, after the
REFERENCES
1. Lebedev, N.N., Khimiya i tekhnologiya osnovnogo or-
ganicheskogo i neftekhimicheskogo sinteza (Chemistry
and Technology of Basic Organic and Petrochemical
Synthesis), Moscow: Khimiya, 1988, 4th ed., p. 592.
2. Averko-Antonovich, L.A. et al., Khimiya i tekhnologiya
sinteticheskogo kauchuka (Chemistry and Technology
INORGANIC MATERIALS Vol. 55 No. 8 2019

802
UVAROV et al.
of Synthetic Caoutchouc), Moscow: Khimiya, KolosS,
DME using a catalytic membrane reactor, Neftekhimiya,
2018, vol. 58, no. 1, pp. 66–71.
2008, p. 357.
9. Fedotov, A.S., Antonov, D.O., Bukhtenko, O.V.,
Uvarov, V.I., Kriventsov, V.V., and Tsodikov, M.V., The
role of aluminum in the formation of Ni–Al–Co con-
taining porous ceramic converters with high activity in
dry and steam reforming of methane and ethanol, Int.
J. Hydrogen Energy, 2017, vol. 42, pp. 24 131–24 141.
10. Tsodikov, M.V., Fedotov, A.S., Antonov, D.O.,
Uvarov, V.I., Bychkov, V.Yu., and Francis, C.L., Hy-
drogen and syn-gas production by dry reforming of fer-
mentation products on porous ceramic membrane–
catalytic converters, Int. J. Hydrogen Energy, 2016,
vol. 41, no. 4, pp. 2424–2431.
11. Fedotov, A.S., Antonov, D.O., Bukhtenko, O.V.,
Uvarov, V.I., Kriventsov, V.V., and Tsodikov, M.V., The
role of aluminum in the formation of Ni–Al–Co-con-
taining porous ceramic converters with high activity in
dry and steam reforming of methane and ethanol, Int.
J. Hydrogen Energy, 2017, vol. 42, no. 38, pp. 24 131–24 141.
3. Bashkatov, T.V. and Zhigalin, Ya.L., Tekhnologiya sin-
teticheskikh kauchukov (Technology of Synthetic Caou-
tchouc), Leningrad: Khimiya, 1987, p. 360.
4. Kondakov, I.L., Sinteticheskii kauchuk ego gomologi i
analogi (Synthetic Caoutchouc: Its Homologs and An-
alogs), Yur’ev: Tipografiya K. Mattisena, 1912, p. 151.
5. Arpe, H.-J. and Hawkins, S., Industrial Organic Chem-
istry, Weinheim: Wiley, 2010, p. 511.
6. Tyuryaev, I.Ya., Teoreticheskie osnovy polucheniya buta-
diena i izoprena metodami degidrirovaniya (Theoretical
Foundations of the Preparation of Butadiene and Iso-
prene via Dehydrogenation), Kiev: Naukova Dumka,
1973, p. 259.
7. Zhuravleva, K.A. and Nazarov, A.A., Preparation of
styrene through ethylbenzene dehydrogenation, Vestn.
Kazansk. Tekhnol. Univ., 2012, vol. 15, no. 12, pp. 149–
152.
8. Fedotov, A.S., Antonov, D.O., Uvarov, V.I., Tso-
dikov, M.V., and Khadzhiev, S.N., Steam reforming of
Translated by O. Tsarev
INORGANIC MATERIALS
Vol. 55
No. 8
2019