In an experimental stand [1] for investigation of properties of hydrogen accumulating the materials investigated
a new type of reactor cleaning and storage of hydrogen.
The applicability of hydrogen purging through metal hydride beds for the purification from nonpoisoning
admixtures is studied experimentally. The main characteristics of the process together with the
main technical barriers of the proposed technology are defined.
Specially designed stainless steel continuous flow reactor filled with LaFe0.1Mn0.3Ni4.8 intermetallic compound
is tested at variable inlet hydrogen/inert gas composition with measuring mass flow, pressure, temperature
and hydrogen content at the outlet both for charging and discharging mode. The estimations of hydrogen
losses and purification capacity show certain advantages of the studied technology in comparison with
PSA-like mode [1], especially from the point of view of operation regime simplification. The evident process
slow-down observed in the experiment is connected with saturation of metal hydride porous bed by hydrogen
and with temperature increase due to high thermal effect at sorption (~ 40 kJ/mole Н2). The ways for heat
and mass transfer optimization together with the range of applicability of the method for fine hydrogen purification
are described and discussed.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3522

Blinov, D.V.

Borzenko, V.I.

Dunikov, D.O.

Malyshenko, S.P.

SocioEconomic Challenges Journal (Sumy State University)

PROCEEDINGS OF THE INTERNATIONAL CONFERENCE NANOMATERIALS: APPLICATIONS AND PROPERTIES 
Vol. 1 No 3, 03AET07(3pp) (2012) 
 
 
2304-1862/2012/1(3)03AET07(3) 03AET07-1  2012 Sumy State University 
Experimental Investigations of Hydrogen Purification by  
Purging Through Metal Hydride 
 
D.V. Blinov*, V.I. Borzenko†, D.O. Dunikov, S.P. Malyshenko 
 
Joint Institute for High Temperatures RAS, 13 Bd.2, Izhorskaya str., 125412, Moscow, Russia 
 
(Received 27 June 2012; published online 08 August 2012) 
 
In an experimental stand [1] for investigation of properties of hydrogen accumulating the materials in-
vestigated a new type of reactor cleaning and storage of hydrogen. 
The applicability of hydrogen purging through metal hydride beds for the purification from non-
poisoning admixtures is studied experimentally. The main characteristics of the process together with the 
main technical barriers of the proposed technology are defined. 
Specially designed stainless steel continuous flow reactor filled with LaFe0.1Mn0.3Ni4.8 intermetallic com-
pound is tested at variable inlet hydrogen/inert gas composition with measuring mass flow, pressure, temper-
ature and hydrogen content at the outlet both for charging and discharging mode. The estimations of hydro-
gen losses and purification capacity show certain advantages of the studied technology in comparison with 
PSA-like mode [1], especially from the point of view of operation regime simplification. The evident process 
slow-down observed in the experiment is connected with saturation of metal hydride porous bed by hydrogen 
and with temperature increase due to high thermal effect at sorption (~ 40 kJ/mole Н2). The ways for heat 
and mass transfer optimization together with the range of applicability of the method for fine hydrogen puri-
fication are described and discussed. 
 
Keywords: Hydrogen, Hydrogen storage, Purification, Metal hydrides, Intermetallide. 
 
  PACS numbers: 88.20.fn, 88.30.R – 
 
 
                                                          
* deltaforces@mail.ru 
† h2lab@mail.ru 
1. INTRODUCTION 
 
Traditional for hydrogen storage (compressed gas 
and liquid) have numerous disadvantages making their 
use impossible in some cases [2]. 
Metal hydride hydrogen storage is free of these dis-
advantages [3]. 
For effective treatment of hydrogen by the usу of 
cyclic reactors [1] is a complicated problem having 
some disadvantages:  
 the need for big (bulky) valve assemblies; 
 the need to regulate the process of discharge of im-
purities from a free volume metal hydride reactors; 
 great loss of hydrogen (20%), depending on the re-
quired purity of the product [1]; 
 thermal losses due to cycling heating/cooling of the 
reactors. 
The method presented helps to simplify the tech-
nology of hydrogen purification, get rid of the cyclic 
removal of impurities from the free volume of reactor, 
thus reducing the amount of valves in the system and 
thereby reduce the capital cost of metal-hydride storage 
and purification systems. 
 
2. THE EXPERIMENTAL TECHNIQUE AND THE 
OBJECT OF INVESTIGATION 
 
2.1 The experimental reactor 
 
Experimental reactor (Fig. 1) was charged with 
1629,5 g hydrogen absorbing material LaFe0.1Mn0.3Ni4.8. 
The choice of  LaFe0.1Mn0.3Ni4.8 alloy is due to compara-
tively high mass content of  in hydride  (~ 1,3 mass.%), 
high desorption pressure (Pdes= 0,45 ÷ 0,60 MPa) in the 
working temperature interval (80 ÷ 100 С) and re-
sistance to CO2 admixtures [2-5].  
The reactor is a vertical cylinder which is placed in-
side the alloy LaFe0.1Mn0.3Ni4.8, welded covers with two 
sides. Gas inlet at the top, output - from below of the 
reactor. Intermetallic compound of a multilayer filters is 
limited to steel grid with a typical size of 3 mm to avoid 
the metal hydrides particles entrainment to the piping.  
 
 
Fig. 1 –  Reactor  of hydrogen purification  by purging through 
metal hydride. 1 – inlet pipe, 2 – micron grid, 3 – metal hy-
dride bed, 4 – outlet pipe 
 D.V. BLINOV, V.I. BORZENKO, D.O. DUNIKOV, S.P. MALYSHENKO PROC. NAP 1, 03AET07 (2012) 
 
 
03AET07-2 
2.2 The experimental apparatus 
 
 
 
Fig. 2 – Scheme of the experimental section: 1 - ramp for the 
preparation of the gas mixture, 2 - Experimental Reactor, 3 - 
liquid thermostat, 4 - flow analyzer, 5 -  vacuum pump, 
R - reducer, PG - pressure gauge, V - valve,  FR -  regulator 
of the gas flow rate 
 
Experimental investigations of gaseous hydrogen 
[4] purification with a flow-type reactor were carried 
out at the experimental section (Fig. 2), a complex ex-
perimental stand [1] at JIHT RAS, which consists of a 
ramp for the preparation of the gas mixture (1), of the 
investigated experimental reactor RHOP-1 (2) placed in 
a liquid thermostat (3), the flow analyzer module (4), a 
vacuum pump (5), gas flow controllers (FR), valves (V), 
reducer (R) and pressure sensors (PG). 
 
2.3 The experimental technique  
 
The nitrogen-hydrogen mixtures of various concen-
tration were prepared for the experimental investiga-
tions. The mixture was fed through the upper pipe 
(Pin = 0,5 MPa, see Fig. 3)  while reactor was placed in 
thermal bath Julabo FPW50-HE which maintained 
0°С, the sorption reaction temperature. The flow at the 
inlet and outlet was limited by flow controller (Fig. 4). 
The outlet flow was organized in the following way that 
the maximal amount was absorbed in metal hydride 
bed and depleted mixture was obtained at the outlet. 
The mixture was analyzed in gas analyzer to monitor 
the hydrogen content at the outlet with flow rate 1.1 st. 
l/min . At reaching high outlet hydrogen content values 
(~ 90% for mixture 1.5% N2, ~ 60% for 13% N2 mixture 
and  27% N2 mixture, which corresponds to hydrogen 
mass content in metal hydride  ~ 1.2% mass.) the value 
of bath temperature was changed to 100°С for the start 
of reactor discharge process with hydrogen exhaust to 
the atmosphere. The discharge was conducted till the 
full stop of desorption. 
 
 
Fig. 3 – The absolute input pressure in a reactor while 
charging. 1 - 1,5%N2, 2 – 13%N2, 3 – 27%N2 
 
 
 
Fig. 4 – Flow rate of mixture at the reactor inlet and outlet, 
depending on the impurity content in the initial mixture while 
charging. 1 – 1,5%N2, 2 – 13%N2, 3 – 27%N2 
 
3. RESULTS AND DISCUSSION  
 
One of the main characteristics of MH devices is the 
dynamics of hydrogen sorption i.e., the dependence of 
the mass content of hydrogen in metal hydrides on time 
(Fig. 5). The data show that the velocity sorption by in-
creasing impurities in the initial gas is falling. 
The initial period of purification is characterized by 
zero hydrogen content at the outlet of reactor. This fact 
is connected with sorption of the entire hydrogen fed to 
the reactor with admixture removed from reactor. For all 
the compositions of initial mixtures the interval of zero 
outlet hydrogen content (Fig. 6) is different: for mixture 
1.5% N2 the interval is 0.05% mass. H2, for 13% N2 – 
0,5% mass, for 27% N2 – 0,65% mass.  
Experimental investigations of purging method 
showed the good comparative efficiency of purification 
at lower costs for exhaust organization (Fig. 7). The 
relative losses of hydrogen at the considered method 
account for 36%, 19% and 4% for mixtures 1.5% N2, 
13% N2 и 27% N2 correspondingly (for the charge of 
reactor hydrogen mass content was  ~ 1,2% mass.). 
 EXPERIMENTAL INVESTIGATIONS OF HYDROGEN PURIFICATION… PROC. NAP 1, 03AET07 (2012) 
 
 
03AET07-3 
 
 
Fig. 5 – Dynamics of hydrogen sorption at various purity of  
hydrogen 1 – 1,5%N2, 2 – 13%N2, 3 – 27%N2  
 
 
 
Fig. 6 – The dependence of volumetric concentration of 
hydrogen at the outlet of the reactor and the mass 
concentration of hydrogen in a solid phase for various degrees 
purity of hydrogen 1 – 1,5%N2, 2 – 13%N2, 3 – 27%N2 
 
4. CONCLUSION  
 
1. The developed experimental reactor for purging 
method RHOP - 1 showed good performance and per-
spective of the method usage for hydrogen purification 
by purging through the metal hydride bed at relatively 
low hydrogen losses. The cascade of reactors could lower 
the hydrogen losses at the selected technology.  
 
 
Fig. 7 – Integral losses of hydrogen relatively summary 
amount of purified hydrogen (accumulated) in charge the 
reactor for various degrees purity of hydrogen 1 – 1,5%N2, 2 – 
13%N2, 3 – 27%N2 
 
2. The conducted experimental investigations 
demonstrated advanced efficiencies for higher values of 
admixture content (>10% vol.), than at pressure cycling 
method.  
3. In spite of evident advantages of purging method, 
there are many scientific and technical problems to 
solve, especially connected with the arranging heat and 
mass transfer inside the reactor.  Due to low effective 
thermal conductivity of hydrogen absorbing material  
(lower than 1 W/m К) and big volumetric thermal effect 
of the reaction (35 kJ/mole H2) the modernization of 
the design is needed with respect to heat transfer in-
tensification. The optimization could include the mini-
mization of the metal hydride layer and the increase of 
the area of the heat transfer between the intermetallic 
alloy and cooling agent. 
 
AKNOWLEDGEMENTS 
 
Authors are grateful to the Ministry of Education 
and Science of the Russian Federation for its financial 
support for research, V.D. Zhemerikin for an assistance 
in the experimental studies, S.V. Mitrokhin for develop-
ing hydrogen storage materials, I.A. Romanov for provid-
ing experimental data on the properties of hydrogen 
storage materials, B.P.Tarasov for providing materials 
on effects of impurities on the intermetallic alloys. 
 
 
 
REFERENCES 
 
1. V.I. Borzenko, D.V. Blinov, D.O. Dunikov, S.P. Malyshen-
ko, 18th World Hydrogen Energy Conference 2010, CD, Es-
sen, Germany, May 16-21, 2010. 
2. Atomic – hydrogen energy and technology. Vol.8. Ener-
goatomizdat, 1988.-272 pp. (In Russian). 
3. B.P. Tarasov, M.V. Lototsky, V.A. Yartys, Russ. Chem. 
Journ. L No6, 5 (2006) (in Russian). 
4. D.V. Blinov, V.I. Borzenko, D.O. Dunikov, S.P. Malyshen-
ko, Vestnik MPEI, №2, 44 (2012). 
 


Experimental Investigations of Hydrogen Purification by Purging Through Metal Hydride

Electronic Sumy State University Institutional Repository

PROCEEDINGS OF THE INTERNATIONAL CONFERENCE NANOMATERIALS: APPLICATIONS AND PROPERTIES Vol. 1 No 3, 03AET07(3pp) (2012)   2304-1862/2012/1(3)03AET07(3) 03AET07-1  2012 Sumy State University Experimental Investigations of Hydrogen Purification by  Purging Through Metal Hydride  D.V. Blinov*, V.I. Borzenko†, D.O. Dunikov, S.P. Malyshenko  Joint Institute for High Temperatures RAS, 13 Bd.2, Izhorskaya str., 125412, Moscow, Russia  (Received 27 June 2012; published online 08 August 2012)  In an experimental stand [1] for investigation of properties of hydrogen accumulating the materials in-vestigated a new type of reactor cleaning and storage of hydrogen. The applicability of hydrogen purging through metal hydride beds for the purification from non-poisoning admixtures is studied experimentally. The main characteristics of the process together with the main technical barriers of the proposed technology are defined. Specially designed stainless steel continuous flow reactor filled with LaFe0.1Mn0.3Ni4.8 intermetallic com-pound is tested at variable inlet hydrogen/inert gas composition with measuring mass flow, pressure, temper-ature and hydrogen content at the outlet both for charging and discharging mode. The estimations of hydro-gen losses and purification capacity show certain advantages of the studied technology in comparison with PSA-like mode [1], especially from the point of view of operation regime simplification. The evident process slow-down observed in the experiment is connected with saturation of metal hydride porous bed by hydrogen and with temperature increase due to high thermal effect at sorption (~ 40 kJ/mole Н2). The ways for heat and mass transfer optimization together with the range of applicability of the method for fine hydrogen puri-fication are described and discussed.  Keywords: Hydrogen, Hydrogen storage, Purification, Metal hydrides, Intermetallide.    PACS numbers: 88.20.fn, 88.30.R –                                                             * deltaforces@mail.ru † h2lab@mail.ru 1. INTRODUCTION  Traditional for hydrogen storage (compressed gas and liquid) have numerous disadvantages making their use impossible in some cases [2]. Metal hydride hydrogen storage is free of these dis-advantages [3]. For effective treatment of hydrogen by the usу of cyclic reactors [1] is a complicated problem having some disadvantages:   the need for big (bulky) valve assemblies;  the need to regulate the process of discharge of im-purities from a free volume metal hydride reactors;  great loss of hydrogen (20%), depending on the re-quired purity of the product [1];  thermal losses due to cycling heating/cooling of the reactors. The method presented helps to simplify the tech-nology of hydrogen purification, get rid of the cyclic removal of impurities from the free volume of reactor, thus reducing the amount of valves in the system and thereby reduce the capital cost of metal-hydride storage and purification systems.  2. THE EXPERIMENTAL TECHNIQUE AND THE OBJECT OF INVESTIGATION  2.1 The experimental reactor  Experimental reactor (Fig. 1) was charged with 1629,5 g hydrogen absorbing material LaFe0.1Mn0.3Ni4.8. The choice of  LaFe0.1Mn0.3Ni4.8 alloy is due to compara-tively high mass content of  in hydride  (~ 1,3 mass.%), high desorption pressure (Pdes= 0,45 ÷ 0,60 MPa) in the working temperature interval (80 ÷ 100 С) and re-sistance to CO2 admixtures [2-5].  The reactor is a vertical cylinder which is placed in-side the alloy LaFe0.1Mn0.3Ni4.8, welded covers with two sides. Gas inlet at the top, output - from below of the reactor. Intermetallic compound of a multilayer filters is limited to steel grid with a typical size of 3 mm to avoid the metal hydrides particles entrainment to the piping.    Fig. 1 –  Reactor  of hydrogen purification  by purging through metal hydride. 1 – inlet pipe, 2 – micron grid, 3 – metal hy-dride bed, 4 – outlet pipe  D.V. BLINOV, V.I. BORZENKO, D.O. DUNIKOV, S.P. MALYSHENKO PROC. NAP 1, 03AET07 (2012)   03AET07-2 2.2 The experimental apparatus    Fig. 2 – Scheme of the experimental section: 1 - ramp for the preparation of the gas mixture, 2 - Experimental Reactor, 3 - liquid thermostat, 4 - flow analyzer, 5 -  vacuum pump, R - reducer, PG - pressure gauge, V - valve,  FR -  regulator of the gas flow rate  Experimental investigations of gaseous hydrogen [4] purification with a flow-type reactor were carried out at the experimental section (Fig. 2), a complex ex-perimental stand [1] at JIHT RAS, which consists of a ramp for the preparation of the gas mixture (1), of the investigated experimental reactor RHOP-1 (2) placed in a liquid thermostat (3), the flow analyzer module (4), a vacuum pump (5), gas flow controllers (FR), valves (V), reducer (R) and pressure sensors (PG).  2.3 The experimental technique   The nitrogen-hydrogen mixtures of various concen-tration were prepared for the experimental investiga-tions. The mixture was fed through the upper pipe (Pin = 0,5 MPa, see Fig. 3)  while reactor was placed in thermal bath Julabo FPW50-HE which maintained 0°С, the sorption reaction temperature. The flow at the inlet and outlet was limited by flow controller (Fig. 4). The outlet flow was organized in the following way that the maximal amount was absorbed in metal hydride bed and depleted mixture was obtained at the outlet. The mixture was analyzed in gas analyzer to monitor the hydrogen content at the outlet with flow rate 1.1 st. l/min . At reaching high outlet hydrogen content values (~ 90% for mixture 1.5% N2, ~ 60% for 13% N2 mixture and  27% N2 mixture, which corresponds to hydrogen mass content in metal hydride  ~ 1.2% mass.) the value of bath temperature was changed to 100°С for the start of reactor discharge process with hydrogen exhaust to the atmosphere. The discharge was conducted till the full stop of desorption.   Fig. 3 – The absolute input pressure in a reactor while charging. 1 - 1,5%N2, 2 – 13%N2, 3 – 27%N2    Fig. 4 – Flow rate of mixture at the reactor inlet and outlet, depending on the impurity content in the initial mixture while charging. 1 – 1,5%N2, 2 – 13%N2, 3 – 27%N2  3. RESULTS AND DISCUSSION   One of the main characteristics of MH devices is the dynamics of hydrogen sorption i.e., the dependence of the mass content of hydrogen in metal hydrides on time (Fig. 5). The data show that the velocity sorption by in-creasing impurities in the initial gas is falling. The initial period of purification is characterized by zero hydrogen content at the outlet of reactor. This fact is connected with sorption of the entire hydrogen fed to the reactor with admixture removed from reactor. For all the compositions of initial mixtures the interval of zero outlet hydrogen content (Fig. 6) is different: for mixture 1.5% N2 the interval is 0.05% mass. H2, for 13% N2 – 0,5% mass, for 27% N2 – 0,65% mass.  Experimental investigations of purging method showed the good comparative efficiency of purification at lower costs for exhaust organization (Fig. 7). The relative losses of hydrogen at the considered method account for 36%, 19% and 4% for mixtures 1.5% N2, 13% N2 и 27% N2 correspondingly (for the charge of reactor hydrogen mass content was  ~ 1,2% mass.).  EXPERIMENTAL INVESTIGATIONS OF HYDROGEN PURIFICATION… PROC. NAP 1, 03AET07 (2012)   03AET07-3   Fig. 5 – Dynamics of hydrogen sorption at various purity of  hydrogen 1 – 1,5%N2, 2 – 13%N2, 3 – 27%N2     Fig. 6 – The dependence of volumetric concentration of hydrogen at the outlet of the reactor and the mass concentration of hydrogen in a solid phase for various degrees purity of hydrogen 1 – 1,5%N2, 2 – 13%N2, 3 – 27%N2  4. CONCLUSION   1. The developed experimental reactor for purging method RHOP - 1 showed good performance and per-spective of the method usage for hydrogen purification by purging through the metal hydride bed at relatively low hydrogen losses. The cascade of reactors could lower the hydrogen losses at the selected technology.    Fig. 7 – Integral losses of hydrogen relatively summary amount of purified hydrogen (accumulated) in charge the reactor for various degrees purity of hydrogen 1 – 1,5%N2, 2 – 13%N2, 3 – 27%N2  2. The conducted experimental investigations demonstrated advanced efficiencies for higher values of admixture content (>10% vol.), than at pressure cycling method.  3. In spite of evident advantages of purging method, there are many scientific and technical problems to solve, especially connected with the arranging heat and mass transfer inside the reactor.  Due to low effective thermal conductivity of hydrogen absorbing material  (lower than 1 W/m К) and big volumetric thermal effect of the reaction (35 kJ/mole H2) the modernization of the design is needed with respect to heat transfer in-tensification. The optimization could include the mini-mization of the metal hydride layer and the increase of the area of the heat transfer between the intermetallic alloy and cooling agent.  AKNOWLEDGEMENTS  Authors are grateful to the Ministry of Education and Science of the Russian Federation for its financial support for research, V.D. Zhemerikin for an assistance in the experimental studies, S.V. Mitrokhin for develop-ing hydrogen storage materials, I.A. Romanov for provid-ing experimental data on the properties of hydrogen storage materials, B.P.Tarasov for providing materials on effects of impurities on the intermetallic alloys.    REFERENCES  1. V.I. Borzenko, D.V. Blinov, D.O. Dunikov, S.P. Malyshen-ko, 18th World Hydrogen Energy Conference 2010, CD, Es-sen, Germany, May 16-21, 2010. 2. Atomic – hydrogen energy and technology. Vol.8. Ener-goatomizdat, 1988.-272 pp. (In Russian). 3. B.P. Tarasov, M.V. Lototsky, V.A. Yartys, Russ. Chem. Journ. L No6, 5 (2006) (in Russian). 4. D.V. Blinov, V.I. Borzenko, D.O. Dunikov, S.P. Malyshen-ko, Vestnik MPEI, №2, 44 (2012).  

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Experimental Investigations of Hydrogen Purification by Purging Through Metal Hydride

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