NH3 Fuel Conference 2016

September 18-21, 2016, Los Angeles, CA

(9:05-9:30, September 20, 2016)

Yoshitsugu Kojima

Hiroshima University

Institute for Advanced Materials Research

Ammonia Storage Materials Using

Metal Halides and Borohydrides

Cross-ministerial Strategic Innovation

Promotion Program (SIP)

1. Energy and

Environmental Issues

2. Research on

hydrogen carrier

3. Properties and Safety

of Ammonia

4. Ammonia Storage

Materials

5. Hydrogen production

for fuel cell vehicles

6. Summary

Contents

Itsukushima

Shinto ShrineHiroshima Peace

Memorial

Hiroshima

University

Hiroshima

University

●Tokyo

●Osaka

●Sendai

JapanJapan

●Fukushima

700km

1. Energy and Environmental Issues

(1) We have a transportation liquid fuel crisis.

(70% of world energy cash flow is around oil.)

(2) Negative effects of global warming

(sea level rise, abnormal weather etc.)

0.5-1 ℃

Hydrogen

Economy

Japan

Hydrogen

storage

materials2100205020100

32.3(2013)

32.3(2014)

Japan：26%

reduction

Japan：80%

reduction

Glo

ba

l carb

on

em

issio

ns

30.3

billion

tons

(2010)

Compared to 2010,

reduction of CO2

around 40 - 70 %

Year

Global carbon emissions pathways reported by IPCC and COP21

2. Research on hydrogen carrier (hydrogen storage

materials) (1999-2016)

Y. Kojima, H. Miyaoka, T. Ichikawa: "Hydrogen Storage Materials". In Steven L. Suib editor. New and Future Developments

in Catalysis: Batteries, Hydrogen Storage and Fuel Cells Amsterdam, Elsevier, 2013.

Evaluation and characterization of 200 kinds of hydrogen storage materials

H N

Li

Li

H

N

B

CH3-CH3

-CH2-CH

Hydrogen

absorbing alloy

Complex

hydrides

Organic

hydrides

Inorganic

hydrides Carbon materials

Mg

H

LiB HNaB

H

AB2

BCC

NH3: burnable

substance Energy carrier

0

2

4

6

8

0 5 10 15 20 100

10

NaH-NH3BH3

12

Liquid H2

0.1MPa,

20K

Ti1.1CrMn

Activated carbon 20K

Li-Mg-N-H

NaBH4-

4H2O

LiH-NH3

MgH2

Li-C-H

Ti0.22Cr0.39V0.39

NH3

0.1MPa, 240K

1MPa, 298K

NH3BH3AlH3

N2H4-H2O

2LiBH4-MgH2

LiBH4Mg(BH4)2

14

CH3OH-H2O

Light weight

Compact

Gravimetric H2 density /wt%

H2 densities of hydrogen carrier(solid, liquid)

3. Properties and Safety of Ammonia

Hydride(calculated value)

H2 storage materials

(experimental value)

Vo

lum

etr

ic H

2d

en

sit

y /k

gH

2/1

00

L

(Pa

ck

ing

ra

tio

: 5

0%

)Above

1.5 times

of liquid

H2

0 5 10 15Hydrogen storage capacity /wt%

-80

-60

-40

-20

0

Heat

of

form

ati

on

(H

) /k

J/m

olH

2

20

NH3

LaNi5

10% of heat of combustion for H2

Heat of formation and H2 storage capacity of

hydrogen storage materials

H2 GasolineC3H8CH4

-200

-150

-100

-50

0

50

100

150

-250NH3

Fla

sh

po

int

/℃

Transportation 26 tons

by trailer (H2: 4.6 tons)

To

improve

health

hazard,

vapor

pressure

Ammonia concentration 100% deleterious substance

Flammability of ammonia and transportation fuel

-

- -

-

-

-

-

-

++

+ +

++

++

Materials having ionic bond

4. Ammonia Storage Materials

BorohydridesMetal Halides

Bonding State(electronegativity)vs. vapor pressure

LiCl, LiF

LiI, NaCl

NaI, MgCl2CaCl2, NiI2 etc.

LiBH4, NaBH4

KBH4, Mg(BH4)2

Ca(BH4)2, etc.

Ammonium Hydrogen

Sulfate

NH4HSO4

Purpose: Relationship among NH3 pressure,

electronegativities of cation and anion

P-C isotherm for NaBH4-NH3 system

0 1 20.00

0.05

0.10

1st

NH

3 P

ress

ure

(M

Pa)

Amount of absorbed ammonia (mol / mol)

2nd

closed symbol absorption

open symol desorption

3rd

0.09MPa

00 1 2

0.10

0.05

First absorption

White circle

: desorption

NH3 /mol/mol(NaBH4)

NH

3p

res

su

re /

MP

a

Second absorption

Third absorption

NH3 vapor pressure of NaBH4(0.09MPa) < NH3 vapor pressure (0.86MPa)

1/10

1-2mol/mol,

0.09MPa

20C

0 1 2 3 4 5 6100

101

102

103

104

MgCl2 after NH

3 treatment

A

mm

onia

Pre

ssure

(P

a)

Amount of absorbed ammonia (mol / mol MgCl2)

100

101

102

103

104

30 1 2 4 5 6

20C

P-C isotherm for MgCl2-NH3 system

NH

3p

res

su

re /

Pa

NH3 /mol/mol(MgCl2)

1-5mol/mol,

200-400Pa

(2000-4000ppm)

NH3 vapor pressure of MgCl2 < NH3 vapor pressure (0.86MPa)

1/3000

Relation between NH3 pressure of

chloride-NH3 system and electronegativity of cation

Electronegativity of cation

0.8 1.0 1.2 1.4101

102

103

104

105

>8×105

NH

3p

res

su

re/P

a

20C

1mol/mol

2mol/mol

5mol/mol

NH3 content

Large covalency

Electronegativity of anion

2.0 2.5 3.5 4.5103

104

105

>8×105

NH

3p

res

su

re/P

a

LiX-NH3

3.0 4.0

20C

Relation between NH3 pressure of halide MX-NH3 (M:

Na, Li, X: F, Cl, I) system and electronegativity of anion

NaX-NH3

NH3/MX:

1-2mol/mol

Large covalency

0.5 1.5 2.5101

102

103

104

105

>8×105

3.5

Electronegativity difference(χp)

Am

mo

nia

pre

ssu

re /

Pa Below

electronegativity

difference of 2.2,

Ammonia

absorption

NH3 pressure as a function of electronegativity difference

Coordination

number:2

Large covalency

Small ionicity

Small covalency

Large ionicity

Ammonium Hydrogen Sulfate

NH4HSO4＋NH3 (NH4)2SO4

Standard enthalpy change -108kJ/molNH3

Standard entropy change -198J/molK (entropy of NH3: 193J/molK)

NH

3p

ressu

re/P

a

van’t Hoff plot for ammonium hydrogen sulfate-ammonia system

W. D. Scott, F.C. R. Cattell, Atmospheric Environment, 13, 307-317 (1979)

1/T /K-1

0.00360.00320.00280.002410-7

10-5

10-3

10-1

101

Below 10-6Pa

(20C,10-5ppm)

Below 0.1ppm

(0.01Pa)R

S

RT

H0

Pln eq

0-

=

5. Hydrogen production for fuel cell vehicles

Species Concentration

Purity of H2 99.97%

Total hydrocarbons(C1) 2ppm

Water(H2O) 5ppm

Oxygen(O2) 5ppm

N2, Ar 100ppm

He 300ppm

Carbon Dioxide(CO2) 2ppm

Carbon Monoxide(CO) 0.2ppm

Total sulphur compounds 0.004ppm

Formaldehyde 0.01ppm

Formic acid 0.2ppm

Ammonia 0.1ppm

Total halogenated compounds 0.05ppm

NH3

remover

Application

of NH3

storage

materials

Specification of hydrogen fuel for FCV (ISO 14687-2:2012)

NH3

remover

NH3 H2

H2ON2

PurifierCracker

Ammonia decomposition and high

purity H2 supply system

NH3

H2

Press release

July 19, 2016

Hiroshima University,

Showa Denko,

Taiyo Nippon Sanso,

National Institute of

Advanced Industrial Science

and Technology (AIST), and

Toyota Industries developed

technologies to produce

high-purity hydrogen to meet

ISO14687-2 (NH3 ≤0.1ppm, N2

≤1ppm, H2 ≥99.97%) from

ammonia for the first time in

the world.

Hydrogen production for fuel cell vehicles from ammonia

500450400

Temperature /℃550 650

10

102

103

104

105

106

600

Theoretical value

Ru/MgO (Ru: 3wt%)

Res

idu

al am

mo

nia

co

ncen

trati

on

/pp

m

NH3 ≤ 1000ppm(0.1%)

Comparison of ammonia concentration

as a function of reaction temperature

403020100≤0.1

200

400

600

800

1000

50

Recycle by heating:

practically possible

Ammonia storage material

Residual ammonia concentration after

removing of ammoniaR

esid

ual am

mo

nia

co

ncen

trati

on

aft

er

rem

ovin

g o

f am

mo

nia

/pp

m

Accumulation amount of ammonia supply /gNH3/L

Ammonia elimination quantity:

30gNH3/L (long optical path length IR)

Ru/MgO catalyst Ammonia storage material

1Nm3

/h

NH3

NH3 Cracker and remover H2 purifier

H2

about

1Nm3

/h

Ammonia decomposition and high purity

H2 supply system (1Nm3/h)

Future plan: system demonstration

1. Ammonia pressure decreases with the

electronegativity of cation and decrease in the

electronegativity of anion.

2. Ammonia pressure increases with the

electronegativity difference below the value of

2.2.

3. High purity hydrogen gas was produced by Ru-

based catalyst, ammonia storage material and

purification method.

6. Summary

This work was supported by Council for Science,

Technology and Innovation(CSTI), Cross-ministerial

Strategic Innovation Promotion Program (SIP), “energy

carrier”(funding agency : JST)

Acknowledgement

June 2(Sunday)-7(Friday) Tokyo International Forum

Chair: H. Kameyama

Vice Chairs: Y. Kojima, N. Kuriyama, S. Mitsushima,

K. Sakata, H. Uchida

Secretary General: H. Takagi

The 8th World Hydrogen Technologies Convention in

2019 (WHTC 2019), Tokyo

Hosted by Hydrogen

Energy Systems Society

of Japan (HESS)

Supported by

International Association

for Hydrogen Energy

(IAHE)

Tokyo International Forum

Thank you for your attention.