International Conference on Science and Technology for Celebrating the
Birth Centenary of Bangabandhu (ICSTB-2021)
EXPERIMENTAL INVESTIGATION OF ADSORPTION ISOTHERMS
AND HEAT OF ADSORPTION AT HENRY REGION FOR ACTIVATED
CARBON/ETHANOL PAIRS
M. L. Palash1, T. H. Rupam2, A. Pal3, B. B. Saha2,4
1Department
of Electrical and Electronic Engineering, University of Dhaka, Dhaka-1000, Bangladesh
2International Institute for Carbon-Neutral Energy Research (WPI-I2CNER), Kyushu University, 744
Motooka, Nishi-ku, Fukuoka 819-0395, Japan
3Department of Nuclear Engineering, University of Dhaka, Dhaka-1000, Bangladesh
4Mechanical Engineering Department, Kyushu University, 744 Motooka, Nishi-ku,
Fukuoka 819-0395, Japan
Green Asia
Education
Center
International Institute
for Carbon-Neutral
Energy Research
Research fields and interests
Energy crisis
Environment problem
 Conventional heat pump systems are responsible for the carbon
footprints from the usage of considerable amount of electricity and
chemical refrigerants having ODP and high GWP.
2.0
Domestic air-conditioning
1.8
Direct emission (tCO2/kW/year)
Power plant
1.6
Domestic refrigeration
1.4
Commercial refrigeration
1.2
Industrial refrigeration
1.0
Sustainable
development
Utilized more than
15% of electricity
production in the
world
0.8
0.6
0.4
0.2
0.0
R22
HCFC
The outer wall of the Fuzhou (China) Dalijiacheng Building
is densely covered with air conditioner compressor units,
the entire building’s outer wall having over 500 air
conditioning compressor units attached in total and still
increasing.
R410A
R134a
HFC
R32
R1234yf
R1234ze
HFO
R600a
CO2
CO2
Natural
Refrigerant
Comparison of direct emission amount of CO2 per kW/year from
the various system.
https://www.chinasmack.com/most-awesome-wall-of-air-conditioners-in-fuzhou
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2
Research fields and interests
To tackle the energy crisis and
environmental issues
Industry
Solar collector
Hot
water
Adsorption heat pump (AHP) systems being driven
by low-temperature industrial waste heat or solar
heat offer as a promising alternative to
conventional system.
Low-grade heat
Condenser
Evaporator
Desorption
Mechanical
Compressor
Adsorption
Expansion
Valve
Electrical
energy
Thermal
energy
Thermal
Compressor
Adsorption heat pump (AHP)
Schematic of the system
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3
Bridging material science with thermal engineering
Gas molecules
Condenser
Adsorption pairs are
the key element for
improvement
Desorption
Mechanical
Compressor
Adsorption
Expansion
Valve
Electrical
energy
Adhesion of gas molecules
on porous surface of
adsorbent
Thermal
energy
Heat released
Gas molecules
Desorption of gas molecules
at low regeneration
temperature
Thermal
Compressor
Evaporator
Linkage between material science (MS)
and applied thermal engineering (ATE)
(a)
Heat input
Adsorbate molecules in
gaseous phase (Ethanol)
isotherm is an
(b)Adsorption
option for characterization
1.2
30°C
50°C
Adsorption uptake [kg kg-1]
Analysis of
adsorption isotherms
can provides the
possible
improvement of
overall system
performance
1.0
70°C
0.8
0.6
Experimental data
D-A equation
0.4
0.2
0.0
0
Adsorption basics
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Micropores
5
10
15
Equilibrium pressure [kPa]
20
Adsorption isotherm of activated carbonbased adsorbent/ethanol pair
25
4
Porous adsorbents
WPT-AC
Zeolite
Metal organic
frameworks (MOFs)
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Silica gel
Activated carbon
(Commercially prevalent, and good
adsorbent for many gases)
M-AC
Activated carbon
SEM of Maxsorb III
5
Low-cost precursors for AC synthesis
Palm tree
Coconut shell
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Mangrove
Agricultural residue
Bamboo
Utilization of biomass to produce activated carbon is a wise
approach in pollution control strategy in two ways.
 First, it can fix the carbon of biomass that prevents the
production of CO2 or CH4
 Second, it produces AC which is industrially useful and
environmentally benign materials that can go into the
soil and enter natural carbon cycle process.
Conversion of waste biomass into valuable carbon material
can also resolve environmental issues like an accumulation
of waste, which causes air and water pollution during
natural degradation process
6
Activated carbon from biomass
Waste palm trunk
Mangrove
Crushing and drying
two different type of biomasses
the particle size less then 5 mm
100°C – 48 h
Vacuum drying
at 105°C – 1 h
Carbonization
500-600°C – 1 h, 10°C/min
N2 flow : 100 sccm
KOH activation
600 – 900°C – 1 h, 5°C/min
N2 flow : 100 sccm
KOH/carbon = 4 - 6
Post-treatment
washing with HCl and DI water
drying 100°C – 3 h (air oven)
drying 150°C – 12 h (vacuum oven)
Activated carbon
Ref.: Pal et al., Encyclopedia of Renewable
and Sustainable Materials, Oxford:
Elsevier, 4 (2020) 584-595.
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Strategy for development of high performance ACs
Heat transfer characteristics
Adsorption characteristics
Effective
adsorption
capacity
Surface
functional
group
Adsorption
kinetics
Heat of
adsorption
Pore structure
modification
Thermal
conductivity
Packing
density
Thermal
capacity
Degree of
graphitization
Modification factors
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Porous properties of BACs
2.5
2.0
Pore volume:
Present study
Biomass-derived
Petroleum/coal/ Benchmark
coke-derived
3500
3000
2500
2000
1.5
1500
1.0
1000
0.5
500
0.0
0
Surface area m2 g-1
Pore volume [cm3 g-1]
3.0
Surface area
WPT-AC (C500)
M-AC (C500)
WPT-AC (C600)
M-AC (C600)
Maxsorb III
Paulownia wood
Fir wood
Oak wood
Bamboo
A-20 (ACF)
Tamarind wood
Fir wood
Pine sawdust
Norit R1 Extra
BPL
CSAC
Ref.: Pal et al., Appl. Energy 264 (2020) 114720.
Pal et al., Encyclopedia of Renewable and Sustainable Materials, Oxford: Elsevier, 4 (2020) 617-628
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Ethanol adsorption onto BACs
2.5
Ethanol uptake [kg kg-1]
Biomass-derived
ACs/ethanol pairs
2.0
Remarkably high uptake
WPT-AC (C600)
Research results
M-AC (C600)
1.5
MIL 101
1.0
H2-Maxsorb III
Maxsorb III
ACF-A20
Literature
ACF-A15
0.5
0.0
0.5
1.0
1.5
2.0
Pore volume [cm3 g-1]
2.5
3.0
Refs.: Appl. Therm. Eng. 122 (2017) 389–397., Int. J. Heat and Mass Trans. 110 (2017) 7-19.
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Surface area and uptake are not sufficient
Entropy is an important factor in a reversible process
•
Adsorbed phase entropy indicates the driving force to provide a pivot between the
equilibrium and non-equilibrium conditions of an adsorption system.
• Lower values of specific entropy means lower quantity of energy supply is required to
drive the system.
Required
energy supply
Green energy system
Low adsorbed phase entropy
Low heat of adsorption
Schematic of refrigeration system
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Motivation of the experimental investigation
Motivation:
 Experimentally found isotherms and heat of adsorption at Henry region are not commonly available
due to the limitation of conventional measurement techniques.
 The requirement of external energy input depends of entropy, the contribution of morphological
parameters on entropy is still unknown.
Target of the study:
 To measure the Henry region isotherms and Henry constant experimentally.
 To measure the zero-coverage heat of adsorption experimentally.
 To to develop a model relating the entropy and surface morphology.
Obstacles:
 It is required to find the suitable coverage range where the homogeneous distribution of the
surface energy exists.
 Establishing a modeling to relate the energetic behavior with surface morphology.
Studied materials:
Maxsorb III/ethanol pair, WPT-AC/ethanol pair, M-AC/ethanol pair, and H2-Maxsorb III/ethanol pair.
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Experimental
Porous properties of the studied AC samples*:
Adsorbent
Total surface area [m2 g-1]
Pore volume [cm3 g-1]
Maxsorb III (as-received)
3299
1.72
WPT-AC
2927
2.51
M-AC
2924
2.18
H2-Maxsorb III
3019
1.48
Unique features of IGC to conduct measurement at Henry region:
i)
Ability to purge very low concentration of probe/solvents: In IGC the
solvents/probes are kept in the reservoir in a liquid form, which are then
evaporated by controlled pressure and temperature. In pulse mode these controlled
evaporated gas molecules are sent to column using a mass flow controller.
ii) Ability to count molecules rather than measuring mass or weight: The desorbed
solvents are ionized using Flame ignited by hydrogen, and detected by FID detector.
The shape of the FID signals exhibits the number of ions detected within a certain
period of time.
*Ref.: Pal et al., (2017) Heat and Mass Transfer; 110: 7-19
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Experimental technique-Inverse gas
chromatography (iGC)
Inverse Gas Chromatography: It is a standard method of surface characterization. At first the surface dispersive free
energy of the solid stationary phase is determined by using series of linear non-polar molecular probes. Then the specific
surface energy and acid-base properties are determined form the free energy differences between polar and non polar
probe gases.
How it works:
•
From experiment:
From thermodynamics:
Fc,tR,t0 can be measured from IGC experiment
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Inert carrier gas carries probe gases to a
column/tube where sample is placed.
• In the column, probe gases stay for a while.
This small period of staying is due to
adsorption and desorption. And the period
is termed as retention time.
• After this retention, probe gases reach the
detector.
VN = Retention volume
Fc= Flow rate
tR= Retention time
t0 = dead time
j= James-martin correction factor
t0 = Dead time
NA= Avogadro constant
a = cross sectional area of adsorbate
𝛾𝑆𝐷 = Dispersive surface energy of solid
𝛾𝐿𝐷 = Dispersive surface energy of adsorbate
14
Measurement of Henry region isotherms
The measurement is conducted using three steps. In the first step, ethanol are purged at
various concentration and temperature which are then adsorbed in the activated carbon
samples kept in glass column. The adsorbed ethanol are eluded from the surface by the
assistance of helium which are detected in the FID detector.
2150
FID signal [μV]
STEP 1
1650
0.05
0.04
0.03
0.02
0.01
1150
650
150
0
5
10
15
20
25
30
Time [min]
Fig. Simplified illustration of “STEP 1 “to measure isotherm (Maxsorb III/ethanol pair at 303 K)
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Measurement of Henry region isotherms
(cont.)
11900
300
STEP 2
Amount adsorbed [µMol g-1]
Retention volume [ml g-1]
0.01
0.02
11700
0.03
11500
0.04
0.05
11300
STEP 3
250
0.05
0.04
200
0.03
150
0.02
100
0.01
50
0
11100
0
20
40
Partial pressure [Pa]
60
80
The equilibrium partial pressure (P), for each
concentration (or coverage) of vapor in the column,
can be calculated from the chromatographic peak
using the following equation:
h
273.15
P  c .VLoop .
.Pinj
Fc . Ac
TLoop
hc , height of the chromatographic peak
Ac , the area of the peak
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0
10
20
30
40
50
Partial pressure [Pa]
60
70
The adsorbed amount is calculated from the
corresponding retention volume using the following
equation:
n
1
ms
VN
 RT dp
VLoop TLoop , the volume and temperature of the injection loop
Pinj , the partial pressure of the loop
16
Isotherms at Henry region
WPT-AC
M-AC
15
18
12
Ethanol uptake [mg/g]
Ethanol uptake [mg/g]
15
12
T=30 Deg C
T=40 Deg C
T= 50 Deg C
T= 60 Deg C
T= 70 Deg C
T= 80 Deg C
9
6
3
300
600
900
Pressure [Pa]
1200
1500
T=30 Deg C
T=40 Deg C
T=50 Deg C
T=60 Deg C
T=70 Deg C
T=80 Deg C
6
3
0
0
9
1800
0
0
300
600
900
Pressure [Pa]
1200
1500
1800
Isotherms measurement at Henry region using inverse gas chromatography
*Pal et al., (2017) Heat and Mass Transfer; 110: 7-19
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Henry region isotherms of activated
carbon/ethanol pairs
Maxsorb III
M-AC
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WPT-AC
H2-Maxsorb III
18
Comparison of Henry’s constant for different
pairs
Henry constant [µmol g-1 Pa-1]
5
4
3
Maxsorb III
WPT-AC
M-AC
H2-Maxsorb
2
1
0
303
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313
323
333
Temperature [K]
343
353
19
Zero coverage heat of adsorption of activated
carbon/ethanol pairs
4
y = -6078.9x + 19.447
R² = 0.9949
y = -6089x + 19.452
R² = 0.9951
y = -6046.5x + 19.123
R² = 0.9945
0.01
ln P [kPa]
1
0
-1
0.03
2
y = -6031.3x + 19.061
R² = 0.9947
y = -6015.6x + 18.752
R² = 0.9936
y = -6006.2x + 18.714y = -6012.9x + 18.322
R² = 0.9943
R² = 0.9937
-2
y = -6010x + 18.3 y = -6066.5x + 17.728
R² = 0.9934
R² = 0.9935
y = -6043.9x + 17.654
R² = 0.9938
-3
-5
0.0026
0.0027
0.0028
0.0029
0.003
0.0031
1/T [K-1]
0.0032
0.0033
0.05
0.04
0.03
2
0.02
0.0034
ln P [kPa]
y = -6194.9x + 19.529
R² = 0.998
y = -6155.6x + 19.12
R² = 0.9973
-1
Clausius-Clapeyron
equation
M-AC
2.7E-3
y = -5326.3x + 16.313
R² = 0.9856
WPT-AC
2.7E-3
y = -5570.7x + 16.143
R² = 0.9878
2.8E-3
3.0E-3
1/T [K-1]
3.1E-3
3.3E-3
3.4E-3
4
3
0.05
0.04
0.03
2
0.02
y = -6463.8x + 20.483
R² = 0.9985
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3.0E-3
1/T [K-1]
3.1E-3
0
-2
y = -6199.1x + 18.048
R² = 0.9966
2.8E-3
y = -6395.2x + 20.069
R² = 0.9984
1
y = -6395.8x + 19.772
R² = 0.9978
-1
y = -6155.5x + 18.694
R² = 0.9967
-3
2.5E-3
y = -5286.5x + 16.675
R² = 0.9851
0
0.01
0.01
-2
1
-3
2.5E-3
H 0 M  ln P

R
1
 
T 
y = -6223.2x + 19.835
R² = 0.9976
1
0
y = -5324.4x + 17.097
R² = 0.9853
0.01
-2
4
3
0.02
-1
Maxsorb III
-4
y = -5330.3x + 17.348
R² = 0.9871
0.05
0.04
3
ln P [kPa]
2
0.05
0.04
0.03
0.02
ln P [kPa]
3
4
3.3E-3
3.4E-3
y = -6362.2x + 19.244
R² = 0.9975
H2-Maxsorb III
-3
2.5E-3
2.7E-3
2.8E-3
y = -6364.6x + 18.474
R² = 0.9977
3.0E-3
1/T [K-1]
3.1E-3
3.3E-3
20
3.4E-3
Comparison of zero coverage heat of adsorption
54
H2-Maxsorb III
Qst [kJ mol-1]
Heat of adsorption [kJ kg-1]
1400
52
M-AC
50
Maxsorb III
48
46
WPT-AC
1200
1000
800
600
400
200
0
M-AC
44
WPT-AC
this work
42
0.00
0.01
0.02
0.04
0.03
Surface coverage [-]
0.05
Fig. Comparison of heat of adsorption for all studied
samples at different surface coverage.
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0.06
Maxsorb III H2-Maxsorb III
other literature
Fig. Comparison of measured heat of adsorption
with the theoretically found values addressed at
various literature.
21
Entropy modeling
One of the primary focus of this work is to find an explicit relationship between the adsorption phenomenon
with the physical properties of adsorbents and adsorbates, which are essential for the development of
engineered materials. For these purposes, the theoretical modeling of a relationship between the
adsorption phenomenon with morphological property is developed.
According to our developed model
the specific entropy can be written
as,
 K RT 
h 0
s 
 R ln  H

T


P

0
and the surface coverage,
 h 0  T s 0 
  exp 

RT


here, Δh0 is specific enthalpy, KH is
the Henry constant, υp is the
specific pore volume.
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Adsorbent/adsor Tempe Isosteric
rature heat, Δh0
bate pairs
[K]
[kJ mol-1]
Pore
volume,
υp
[cm3 kg1]
Henry
constant,
KH
[kg kg-1
kPa-1]
Specific
entropy,
Δs0
[kJ kg-1 K-1]
Maxsorb
III/ethanol
WPT-AC/ethanol
M-AC/ethanol
328
H2-treated
Maxsorb
III/ethanol
54.23
1.70
0.0589
2.217
49.05
53.13
55.58
2.51
2.18
1.73
0.0411
0.0661
0.0682
1.934
2.1670
2.304
22
Characteristic specific entropy for activated
carbon/ethanol pairs
3.2
3
H2-treated Maxsorb III/ethanol
2.30
Specific entropy, Δs0 [kJ kg-1 K-1]
Specific entropy, Δs0 [kJ kg-1 K -1]
2.40
Maxsorb III/ethanol
2.20
M-AC/ethanol
2.10
WPT-AC/ethanol
2.00
1.90
y = 0.0112x + 1.8354
R² = 0.9993
10
20
30
K H/υp [kg kJ-1]
M-AC/ethanol
2.6
2.4
2.2
2
1.80
0
2.8
WPT-AC/ethanol
Maxsorb III/ethanol
H2-treated Maxsorb III/ethanol
HmAX/Ethanol
40
50
The relation between adsorbed phase specific entropy
and the ratio of Henry constant and total pore volume
of adsorbents at 328 K temperature.
1.8
0.000
0.002
0.004
0.006
0.008
Surface coverage [-]
0.010
0.012
The relation between adsorbed phase specific
entropy and surface coverage at 328 K
The minimum entropy required for ethanol adsorption on carbon-based adsorbents is 1.8354 kJ
kg-1 K-1. Below that no ethanol adsorption will occur as the positive effects of adsorbate/
adsorbent interaction is zero or KH = 0.
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Conclusions
This study comprised of three major findings: i) study of adsorption isotherms at henry
region ii) study of zero coverage heat of adsorption and iii) thermodynamic formulation to relate
adsorption phenomena with the physical properties of the adsorbents and adsorbates.
 Adsorption isotherms at the Henry region were measured using IGC technique in a lower
pressure region (relative pressure < 0.003). All the isotherms were found to be linear indicating
the successful measurement in Henry region.
 Zero coverage heat of adsorption of the studied samples is measured using Clausius-Clapeyron
equation and the isotherm data. In Henry region the isosteric heat of adsorbent remains
constant while the uptake changes for a specific adsorbent. The measured value for zero
coverage heat of adsorption for Maxsorb III, M-AC, WPT-AC, and H2-treated Maxsorb III are
50.35 kJ mol-1, 51.5 kJ mol-1, 44.5 kJ mol-1, and 53.3 kJ mol-1, respectively.
 Using the thermodynamic formulation, a relation between the specific entropy against the ratio
term, KH/ϑP was established. The relation followed a linear trend and cut in the vertical axis at
1.8354 kJ kg-1 indicating the values of ideal entropy of adsorption process for ethanol on
carbonaceous materials. Below that, no ethanol adsorption will occur as the positive effects of
adsorbate/adsorbent interaction would be zero or KH = 0.
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Related recent publications
1. M. L. Palash, T. H. Rupam, A. Pal, A. Chakraborty, B. B. Saha
and R. Wang : Design principles for synthesizing high grade
activated carbons for adsorption heat pumps, Chemical
Engineering Journal Advances, vol.6, pp.100086, 2021 .
(Open access)
2. L. G. Gordeeva, Y. Tu, Q. Pan, M. L. Palash, B. B. Saha, Y. I.
Aristov and R. Wang : Metal-organic frameworks for energy
conversion and water harvesting: a bridge between thermal
engineering and material science, Nano Energy, pp.105946,
2021 . (IF: 16.602)
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25
Our group
Current activities
International Institute for Carbon-Neutral
Energy Research, Kyushu University
Prof. Bidyut Baran Saha
Materials
characterization and
its applicability
System design &
implementation
SAHA Laboratory
Supervisor
Mathematical
modelling, statistical
analysis & simulation
Materials
development
Carbon neutral sustainable energy production approach
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Research activities
Advanced materials
SAHA
Laboratory
Components, system & simulation
Algal Nutrients
Superfood
CO2
Fast algae cultivation
Energy assessment and policy
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Biofuel
Algae, negative CO2 & biofuel
27
Thank you for your
kind attention!
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28
Schematic of adsorption heat pump system
Expansion valve
Condenser
Cooling water inlet
Cooling water outlet
Adsorber (Bed 1)
Cooling
water
outlet
Cooling
water
inlet
V2
BACs
Valves path
V1
V4
BACs
Hot water
inlet
Chilled water inlet
Evaporator
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V3
Desorber (Bed 2)
Hot water
outlet
Chilled water outlet
Backup slides
29
Adsorption basic
Adsorption: It is a process that occurs when a gas or liquid solute accumulates on the
surface of a solid or a liquid (adsorbent), forming a molecular or atomic film (adsorbate).
Absorption
is a bulk
phenomeno
n
Adsorption
is a surface
phenomena
Physisorption
arises due to
Van Der
Waal’s forces
Chemisorptio
n arises due
to chemical
bond
formation
Key factors for adsorption
 Surface area
 Pore volume
 Pore size
VS
Fig 1. Absorption vs Adsorption
Physisorption
Chemisorption
Fig 2. Physisorption vs Chemisorption
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Different pore structure of
activated carbon
Backup slides
30
Activation process
Precursor materials
Physical activation
Steam
CO2
N2
Chemical activation
Ar/other inert gas
Dehydrating chemical
agents (H3PO4, KOH,
K2CO3 etc.) impregnation
of raw material
Carbonization of precursor in inert
atmosphere at temp.>400°C
Activation in inert atmosphere at temp. >800°C
Carbonization of precursor in
inert atmosphere at temp. >400°C
Dehydrating chemical agents
(H3PO4, KOH, K2CO3 etc.)
impregnation of raw material
Activationin inert atmosphere at temp. >500°C
Washing and drying
Activated carbon
Activated carbon
WPT-AC
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M-AC
Backup slides
31
Synthesis of biomass-derived ACs: carbonization &
activation experiment
N2 outlet
N2 inlet
During carbonization
Carbon felt
Stainless steel
Tube
Heater
Nickel
ribbon
(a)
Photograph of carbonized (a) WPT and
(b) Mangrove
During activation
S ample
container
Heater
High-temperature
furnace
Temperature
controller
Carbonized sample
Schematic diagram of experimental setup
for carbonization and KOH activation
reactor.
*In collaboration with Prof. Yoon & Prof. Miyawaki, IMCE, Kyushu University
University of Dhaka
(b)
Elemental compositions of carbonized WPT and
mangrove at 500ºC.
KOH
Elemental composition (%)
C
H
N
Odiff.
Ash
(%)
WC500
72.35
2.97
0.48
19.56
4.64
MC500
81.91
3.20
0.28
10.97
3.64
Sample
Backup slides
32
Porous properties of BAC
Sample
Total
surface
area
[m2 g-1]
WC500A600K4
WC500A700K4
WC500A800K4
WC500A900K4
WC500A900K6
WC600A900K6
MC500A600K4
MC500A700K4
MC500A800K4
MC500A900K4
MC500A900K6
MC600A900K6
1402
2583
2985
2771
2848
2927
2131
2878
2919
2925
2911
2924
University of Dhaka
External
Micropore Total pore Average
surface
Activation
volume volume pore width
area
yield [%]
3 g-1]
3 g-1]
[cm
[cm
[nm]
[m2 g-1]
14.10
22.93
32.28
46.33
103.99
62.52
10.68
17.47
20.09
28.21
58.99
34.19
0.62
1.44
1.90
1.99
2.69
2.41
0.90
1.56
1.69
1.92
2.58
2.13
0.65
1.48
1.96
2.07
2.87
2.51
0.91
1.60
1.72
1.97
2.68
2.18
0.90
1.13
1.29
1.46
1.96
1.68
0.84
1.09
1.16
1.33
1.81
1.47
50.17
43.04
37.87
30.99
20.54
27.27
54.61
49.84
52.46
41.03
32.14
37.54
Backup slides
33
CO2 adsorption onto BACs
Current benchmark
1.0
Biomass-derived
ACs/CO2 pairs
W [g g-1]
0.9
0.8
Research results
0.7
Effective uptake,
0.6
0.5
Maxsorb III
0.4
Composite
0.3
0.2
A-20
Norit RB3 (AC1)
Literature
Norit darco (AC2)
Norit darco
(AC1)
Norit R1 extra
A-10
BPL
CSAC Norit darco (AC3)
0.1
0.0
0.0
1.0
2.0
3.0
3
-1
Pore volme [cm g ]
4.0
Ref.: Pal et al., Appl. Energy 264 (2020) 114720.
University of Dhaka
Backup slides
34
Pore size and surface area analysis
Ultra micro-pore
Micro-pore
Meso-pore
SEM images of activated carbon
Pore size distribution from NLDFT
analysis of N2 adsorption
Mangrove based
activated carbon
BET surface area = 2927 m2/g
Average pore diameter = 1.5 nm
Pore volume = 2.18 cm3/g
Ref.: Pal et al., Encyclopedia of Renewable and Sustainable Materials,
Oxford: Elsevier, 4 (2020) 584-595
University of Dhaka
Backup slides
35
Available experimental aparatus
Surface energy
analyzer (iGC)
Differential scanning
calorimetry
University of Dhaka
Scanning probe
microscopy
Constant volume
variable pressure
(CVVP) setup
Porous properties
analyzer (3Flex)
Material synthesis
Carbon neutral sustainable
energy production
approach
Biodiesel Fermentatio
Extraction
n Tank
Laser flash:
LFA457
Thermogravimetri
c analyzer
Backup slides
36