International Journal of Renewable Energy Development
Int. J. Renew. Energy Dev. 2023,12(2), 270-276
| 270
https://doi.org/10.14710/ijred.2023.48432
ISSN: 2252-4940/© 2023.The Author(s). Published by CBIORE
Contents list available at IJRED website
International Journal of Renewable Energy Development
Journal homepage: https://ijred.undip.ac.id
Utilization of Cassava Peel (Manihot utilissima) Waste as an Adhesive
in the Manufacture of Coconut Shell (Cocos nucifera) Charcoal
Briquettes
Bayu Rudiyantoa* , Intan Rida Agustinaa, Zeni Ulmaa, Dafit Ari Prasetyoa, Miftah Hijiriawanb ,
Bambang Piluhartoc, Totok Prasetyod
aEnergy Engineering Laboratory, Departement of Renewable Energy Engineering, Politeknik Negeri Jember, Jl. Mastrip 164 Jember 68121, Indonesia
bGraduate Program of Mechanical Engineering, Universitas Sebelas Maret, Jl. Ir. Sutami No.36 Surakarta, 57126, Indonesia
cDepartment of Chemistry, Universitas Jember, Jl. Kalimantan 37 Kampus Tegalboto, Jember 68121, Indonesia
cDepartment of Mechanical Engineering, Politeknik Negeri Semarang, Jl. Prof. H. Soedarto S.H. Semarang, 50275, Indonesia
Abstract. Coconut shells and waste cassava peels could be used as the main raw material for biomass briquettes for alternative energy sources in
Indonesia. This study aims to analyze the quality of briquettes based on a coconut shell and cassava peel adhesive through proximate analysis with
three treatment ratio variations. The ratio of coconut shell to cassava peel used varied from V1 (75%:25%), V2 (70%:30%), and V3 (65%:35%). Based
on the result, the charcoal briquettes produced have a density of 0.61 gram/cm³-0.66 gram/cm³, water content of 5.51%-7.85%, ash content of 1.50%-
2.86%, combustion rate of 0.021 gram/s-0.026 gram/s, and the calorific value of 6,161 cal/gram-6,266 cal/gram. However, all the treatment variations
appropriate the SNI 01-6235-2000, the national standard of Indonesia for the quality of charcoal briquette, which includes the calorific value (>5,000
cal/gram), moisture content (<8%), and ash content (<8%). Briquettes with the best quality were generated by V1 with a density of 0.66 gram/cm³,
water content of 5.51%, ash content of 1.50%, combustion rate of 0.026 gram/s, and calorific value of 6,266 cal/gram. Furthermore, briquette material
from the coconut shell waste with natural cassava peel adhesive can be feasible as an alternative fuel.
Keywords: Biomass, Briquettes, Cassava Peel Waste, Coconut Shell, Proximate Analysis
@ The author(s). Published by CBIORE. This is an open access article under the CC BY-SA license
(http://creativecommons.org/licenses/by-sa/4.0/).
Received: 20th August 2022; Revised: 24th Nov 2022; Accepted: 2nd Jan 2023; Available online: 12th Jan 2023
1. Introduction
The amount of energy needed has increased due to Indonesia's
population growth. In 2021, energy consumption from coal
could reach 17% of the total national energy consumption mix
(BPPT, 2021). This certainly encourages the importance of using
alternative and renewable energy sources. In this case, biomass
is a renewable energy source that can be used as an alternative
fuel to replace fossil fuels with abundant availability (Budi
Surono, 2019; Sunardi, Djuanda, & Mandra, 2019; Tzelepi et al.,
2020). Biomass includes agricultural, plantation, forest waste,
and organic components from industry and households (Yana,
Nizar, Irhamni, & Mulyati, 2022). Furthermore, the development
of biomass as an alternative energy source has many challenges,
and one of them is the production process (Cuong et al., 2021;
Dani & Wibawa, 2018; Yana et al., 2022). However, the briquette
is a biomass product that can be produced through a simple
process with economic value, high heat content, and abundant
availability of raw materials to compete with other fuels (Sunardi
et al., 2019).
Various types of waste can be used as raw materials to
produce briquettes while solving the waste management
* Corresponding author
Email: bayu_rudianto@polije.ac.id (B. Rudiyanto)
problem (Ardelean et al., 2022; Bazhin, Kuskov, & Kuskova,
2019; Ganesan & Vedagiri, 2022; Vaish, Sharma, & Kaur, 2022).
Coconut shell (Cocos nucifera) is a waste product that can be
utilized to produce charcoal briquettes. In this case, Indonesia
has quite extensive coconut plantations that can be used. This
follows statistical data from the Directorate General of
Plantation (2021) that the total area of coconut plantations is
3,401,893 Ha, with a total production of 2,839,852 tons. Besides,
the coconut shell also contains a high calorific value reaching
7,283.5 cal/gram (Nurhilal, Suryaningsih, & Indrana, 2018), and
the coconut shell water content is only 10.03% (Ghafar, Halidi,
& So’aib, 2020). However, in charcoal briquette production,
natural adhesives are usually needed to support the quality of
the briquettes. The addition of adhesive is meant to reduce the
briquette’s pores and give them a solid structure, permitting
them to be shipped and stored without being easily destroyed
(Jiang et al., 2022; Kamunur, Ketegenov, Kalugin, Karagulanova,
& Zhaksibaev, 2022). In addition, the coconut shell charcoal's
fine grains are combined with the adhesive substance to be
molded as required.
Research Article
https://doi.org/10.14710/ijred.2023.48432
https://doi.org/10.14710/ijred.2023.48432
mailto:bayu_rudianto@polije.ac.id
https://orcid.org/0000-0002-4708-629X
https://orcid.org/0000-0002-4667-2908
http://crossmark.crossref.org/dialog/?doi=10.14710/ijred.2023.48432%26domain=pdf
B. Rudiyanto et al Int. J. Renew. Energy Dev 2023, 12(2), 270-276
|271
ISSN: 2252-4940/© 2023. The Author(s). Published by CBIORE
In this case, various adhesive materials in the manufacture
of briquettes have been developed (Helwani et al., 2020;
Maulina, Sarah, Misran, & Anita, 2021; Suryaningsih, Resitasari,
& Nurhilal, 2019). Cassava peel (Manihot Utilissima) is one of the
materials that can be utilized as an alternative due to its
availability to assist the production of coconut shell briquettes
as a biomass raw material. It can be seen that the production of
cassava plants in Indonesia can reach 19,053,748 tons (Ministry
of Agriculture, 2021). Cassava peel has the potential to be used
as an adhesive in the production of briquettes due to its
moisture content of 9.93-11.46%, volatile materials of 77.93-
81.93%, ash content of 1.93-4.36%, fixed carbon content of
13.44-15.51%, lignin content of 6.5-16.0%, cellulose content of
5.5-14.5%, hemicellulose content of 41.0-56.0%, and calorific
value of 3,843.84 cal/gram (Hirniah, 2020; Kayiwa, Kasedde,
Lubwama, & Kirabira, 2021a, 2021b). Furthermore, cassava peel
has a carbohydrate content of about 30.15% that can be used as
an adhesive (Anggraeni, Girsang, Nandiyanto, & Bilad, 2021;
Kariuki, Muthengia, Erastus, Leonard, & Marangu, 2020).
Proximate testing is needed to determine the quality of
briquettes based on SNI. However, due to its ready-to-use
product characteristic, proximate testing is required to
determine the ability of briquettes as fuel. In charcoal briquette
production, it is necessary to consider the value of water
content, volatile matters, ash, solid carbon (fixed carbon), and
calorific value as the main parameters of the quality of
briquettes. The water content indicates the ease of burning, and
briquettes are easier to mold when the water content is high.
Volatile matter, ash, and solid carbon as total fixed carbon refer
to the amount of smoke when the briquettes are burned (Srisang
et al., 2022). Besides, the calorific value represents the energy
produced from briquettes and the ease of burning (Adeleke,
Odusote, Ikubanni, Olabisi, & Nzerem, 2022; Guo et al., 2020;
Velusamy, Subbaiyan, Kandasamy, Shanmugamoorthi, &
Thirumoorthy, 2022).
The novelty of this research is the composition of raw
materials and adhesives for the production of the briquettes.
Although coconut shell has been commercialized as a raw
briquette material, tapioca flour is still used as an adhesive.
However, cassava peel is an excellent adhesive material
because it has a starch content above 30%. Therefore, this
research aims to determine the concentration level between
coconut shell biomass and cassava peel natural adhesive
according to the five aspects based on the SNI 01-6235-2000 in
Indonesia. This is expected to produce a suitable correlation to
obtain the development of charcoal briquettes better. As a
result, the production of charcoal briquettes as an alternative
fuel with high economic value, wide availability, and simplicity
of access, can serve in the development of new and ecologically
friendly energy sources.
2. Method
2.1 Development of Coconut Shell (Cocos nucifera) Charcoal
Briquettes Material
In this research, coconut shell waste is used as raw material for
briquettes production, and cassava peel waste is used as an
adhesive. The chemical and physical properties of the coconut
shell and cassava peel is shown in Table 1 and 2. Coconut shell
as the raw material that has been dried is then pyrolyzed using
a furnace at a temperature of 300℃ for 7 hours (Rizal et al., 2020;
Sarkar & Wang, 2020; Tu et al., 2021). During the pyrolysis
process, the raw material of coconut shells is charred evenly.
The result of the coconut shell that has been charcoaled is then
pounded.
Table 1
Chemical and physical properties of coconut shell (Kabir Ahmad et al.,
2022)
Parameters Properties Description
Proximate Analysis
Moisture Content 5.56%
Volatile Matter 70.82%
Fixed Carbon 21.80%
Ash 1.80%
Ultimate Analysis
C 40.08%
H 5.22%
N 0.22%
S 0.17%
O 54.31%
Potential as Energy
Source
Porosity 24.39%
Compressibility Index 40.24%
Calorific Value 19.4 MJ/kg
Fuel Value Index 4441
Table 2
Chemical and physical properties of cassava peel (Kayiwa et al., 2021a)
No. Properties Description
1 Moisture Content 9.77-11.50%
2 Volatile Matter 78.22-82.31%
3 Fixed Carbon 13.44-15.51%
4 Ash Content 1.85-4.40%
5 Lignin 6.5-16.0%
6 Cellulose 5.5-14.5%
7 Hemicellulose 41.0-56.0%
Then, the coconut shell is sieved using a 40-mesh which aims to
produce a fine, uniform particle size, and suitable as a briquette
material (Abyaz, Afra, & Saraeyan, 2020; Meytij, Santoso,
Rampe, Tiwow, & Apita, 2021; Setter, Sanchez Costa, Pires de
Oliveira, & Farinassi Mendes, 2020).
The production of cassava peel adhesive begins with
cleaning the attached peel dirt. Then, the cassava peel is dried
and mashed using grinding. When the cassava peel has been
processed into flour, it is filtered, combined with hot water in a
1:2 ratio, and stirred thoroughly to remove lumps. The purpose
of the hot water addition is to make the mixing process easier.
Variations in the mixture of briquette raw materials were
carried out using coconut shell charcoal which had been
mashed using adhesive homogeneously with a predetermined
composition, namely variation 1 (V1), variation 2 (V2), and
variation 3 (V3), as shown in Table 3. Furthermore, the finished
raw material mixture is placed into the briquette mold in the
shape of a cylinder with a material weight of 30 grams. The
briquette mixture was flattened to a height of 5.7 cm, then
pressed 60% to produce briquettes with a height of 2.3 cm. The
briquettes harden during the one-minute pressure hold. The
drying process was then continued by heating for 4 hours at
105°C in an oven. The briquettes were consequently stored at
room temperature for 24 hours.
Table 3
Composition variations of coconut shell charcoal briquettes
Variation
Name
Briquettes Material Composition
Coconut Shell
Charcoal
Cassava Peel
Adhesive
V1 75% (22.5 grams) 25% (7.5 grams)
V2 70% (21 grams) 30% (9 grams)
V3 65% (19.5 grams) 35% (10.5 grams)
B. Rudiyanto et al Int. J. Renew. Energy Dev 2023, 12(2), 270-276
|272
ISSN: 2252-4940/© 2023. The Author(s). Published by CBIORE
Table 4
Specifications of instruments used in the study
Instrument Specification
Wire mesh GB/T6003.1-2012 40 mesh
Heater UNB 400
(oven)
230 VAC; 6.1 A; 50/60 Hz
Furnace Carbolite ELF
11/6B
230 VAC; 9.6 A: 2000 Watt; Max temp
1100℃
M20 Universal Mill
(Grinder)
230/115 ±10% VAC; 50/60 Hz; 550
Watt; 20,000 rpm; 250 ml
IKA © 2000 Bomb
Calorimeter
230/115 VAC; 50/60 Hz; 1.8 kW;
measurement range 40,000 J
2.2 Experimental and Testing Instruments
In the manufacturing and analysis performed, this research uses
several types of equipment, such as a 40-mesh sieve, mortar,
briquette press, heater (oven), grinding, baking sheet, mixing
tank, pan, cup, analytical balance, pyrolysis equipment, IKA ©
2000 Bomb Calorimeter, stopwatch, and caliper. Further details
for the instrument used in this study are shown in Table 4.
2.3 Quality Test of Briquettes
The quality testing of coconut shell charcoal briquettes included
density, moisture content, ash, combustion rate, and calorific
value. Density can be examined by measuring the mass of
briquettes and the volume of briquette samples using Equation
(1):
𝜌 =
𝑚
𝑣
(1)
Whereas 𝜌 (g/cm3) is density, 𝑚 (g) is the mass of briquettes,
and 𝑣 (cm3) is the volume of the briquettes.
Moisture content can be tested by weighing the sample to
determine the initial weight and then heated in an oven at 105℃
for 6 hours. The sample was weighed again to decide its final
weight after being dried in the oven for an hour. The water
content can be calculated using Equation (2):
𝑀𝐶 =
𝑋1−𝑋2
𝑋1
100% (2)
Where 𝑀𝐶 is moisture content, 𝑋1 (g) is the initial weight of the
sample, and 𝑋2 (g) is the final weight of the sample.
Ash content is the residue from burning briquettes that are
not completely burned. The ash content test was carried out by
weighing the empty weight of the cup, then 1 gram of the sample
in the cup was heated in the furnace gradually at a temperature
of 450-950℃ for 1-2 hours and then allowed to stand at room
temperature until the temperature was normal. Equation (3) can
calculate ash content as follow:
𝐴𝐶 =
𝐵−𝐴
𝐶−𝐴
𝑥 100% (3)
Where 𝐴𝐶 is ash content, 𝐴 is the weight of an empty cup, 𝐵 is
the weight of the cup and ash, and 𝐶 is the weight of the cup and
the sample.
The rate of burning of briquettes is determined by the weight
of the briquettes burned over a certain period using Equation
(4):
𝑉 =
𝑚𝑡
𝑡
(4)
Where 𝑉 (g/s) is the rate of burning of briquettes, 𝑚𝑡 (g) is the
mass of the burned briquettes, and 𝑡 (second) is the required
burning time.
Fig. 1 Briquette preparation schematic diagram
The heat produced by briquettes and oxygen at a fixed
volume can be evaluated using a bomb calorimeter to determine
the calorific value. Figure 1 shows the method used in this study
to produce coconut shell charcoal briquettes using
waste cassava peel as an adhesive.
2.4 Data Analysis
In this study, we performed a quantitative analysis of density,
moisture content, ash content, combustion rate, and calorific
value of the coconut shell charcoal briquettes production using
adhesive from waste cassava peel in each variation in the ratio
of material composition. The analysis was carried out to
determine whether the values of the various parameters
complied with the Indonesian National Standard (SNI) 01-6235-
2000. Moreover, a one-way Analysis of Variance (ANOVA) test
was conducted to investigate whether variations in the material
composition used to create adhesive from waste cassava peel
during the production of coconut shell charcoal briquettes
affected each of the parameters analyzed in this study.
Furthermore, posthoc analysis using the Tukey method was
carried out to determine the significant differences between
each variation (Aransiola, Oyewusi, Osunbitan, & Ogunjimi,
2019; Karimibavani, Sengul, & Asmatulu, 2020; Niño, Arzola, &
Araque, 2020).
3. Results and Discussion
3.1 Density
The briquette density test was carried out using the ratio of mass
and volume. The homogeneity and size of the charcoal are
affected by the density the briquettes produce. The results of
the density measurement of charcoal briquettes V1, V2, and V3
are presented in Figure 2.
Fig. 2 Density of coconut shell briquettes with cassava peel adhesive
0.66
0.63
0.61
0.54
0.56
0.58
0.60
0.62
0.64
0.66
0.68
0.70
V1 (75%:25%) V2 (70%:30%) V3 (65%:35%)
D
e
n
s
it
y
(
g
r
a
m
/c
m
³)
B. Rudiyanto et al Int. J. Renew. Energy Dev 2023, 12(2), 270-276
|273
ISSN: 2252-4940/© 2023. The Author(s). Published by CBIORE
Table 5
Density analysis using the Tukey method with 95% confidence
Variation N Mean Grouping
V1 3 0.66456 A
V2 3 0.63108 B
V3 3 0.61050 C
Based on Figure 2, it can be seen that the highest density
value is in V1 of 0.66 g/cm3 with a ratio of coconut shell to
cassava peel adhesive of 75%:25%, while the lowest value is in
V3 with a ratio of coconut shell to cassava peel adhesive of
65%:35%. However, the values of the three densities are not
much different, but the treatment value in V1 shows the results
of better briquette density compared to other variations. This is
due to the amount of adhesive that meets the void ratio formed
by the particle size of 40 mesh.
High pressure can also increase the density value. It follows
the research conducted by Sunardi et al. (2019) about the
characteristics of corncob briquettes with a pressure of 44.80
kg/cm3 and a particle size of 60 mesh, which produces a higher
density level than corncob briquettes using a pressure of 22.42
kg/cm3 with a particle size of 40 mesh. Consequently, the
adhesive will tend to fill the surface of the charcoal as the bonds
between the molecules of the charcoal become stronger,
reducing the cavity filled with water or air (Satya, Raju,
Praveena, & Jyothi, 2014). Therefore, the higher the density
value of the briquettes, the smaller the cavity and the rate of
combustion is slower (Haryanti, Wardhana, & Suryajaya, 2020).
Furthermore, in statistical analysis using the one-way ANOVA
method to determine the effect of variations in the composition
of coconut shell charcoal and cassava peel waste, it is known
that the P-value is <0.05, representing that the composition
affects the density value of the briquettes. In the post hoc Tukey
analysis, it is also known that each variable V1, V2, and V3 is
significantly different from each other, as shown in Table 5.
3.2 Moisture Content
Briquettes have hygroscopic properties or easily absorb water,
which shows that the value of water content needs to be
considered because it can affect the quality of the briquettes
produced. In this case, the moisture content of coconut shell
briquettes with cassava peel adhesive ranged from 5.51-7.85%,
as presented in Figure 3.
Figure 3 shows that the highest water content was
obtained in treatment V3 at 7.85%, while the lowest water
content was found in V1 at 5.51%. Treatment V1 with a ratio of
coconut shell to cassava peel adhesive of 75%:25% had better
briquette quality than other variations.
Fig. 3 Moisture content of coconut shell briquettes with cassava peel
adhesive
Table 6
Moisture content analysis using the Tukey method with 95% confidence
Variation N Mean Grouping
V3 3 7.8525 A
V2 3 6.503 B
V1 3 5.511 C
This is due to the low water content, and the cassava peel
adhesive that blends with coconut shell charcoal will be tighter
because its pores become smaller. The high and low water
content produced can be influenced by the type and percentage
of adhesive used to manufacture briquettes (Kong, Loh,
Bachmann, Rahim, & Salimon, 2014). The addition of more
adhesive causes the water contained in the adhesive to enter
the pores of the charcoal (Permatasari & Utami, 2015)
Based on Figure 3, it can be seen that the smaller the
percentage of adhesive used, the smaller the water content,
which means the quality of the briquettes produced will be
better. This is in line with the research by Maryono et al. (2013)
about the quality of coconut shell charcoal briquettes with the
addition of higher levels of starch adhesive will produce higher
water content as well. The maximum moisture content of
charcoal briquettes is 8%, according to SNI 01-6235-2000. In
this case, the water content in each treatment has met the SNI
standard because it is below 8%, indicating that the coconut
shell briquettes with cassava peel adhesive are suitable for
alternative fuels. However, the P-value of the one-way ANOVA
test is <0.05, which indicates that the variation in the
composition of coconut shell charcoal with cassava peel waste
affects the value of the resulting water content. Moreover, the
post hoc Tukey's analysis results show that each variation V1,
V2, and V3 is significantly different, as shown in Table 6.
3.3 Ash Content
Ash content is one of the references to determine the quality of
briquettes. Ash content can affect the calorific value and carbon.
The ash content produced in this study ranged from 1.50-2.86%.
The results of the ash content test are presented in Figure 4.
Fig. 4 Ash content of coconut shell briquettes with cassava peel
adhesive
Table 7
Ash content analysis using the Tukey method with 95% confidence
Variation N Mean Grouping
V3 3 2.8579 A
V2 3 2.6569 A
V1 3 1.501 B
5.51
6.50
7.85
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
9.00
V1 (75%:25%) V2 (70%:30%) V3 (65%:35%)
M
o
is
tu
r
e
C
o
n
te
n
t
(%
)
1.50
2.66
2.86
0.00
0.50
1.00
1.50
2.00
2.50
3.00
3.50
V1 (75%:25%) V2 (70%:30%) V3 (65%:35%)
A
s
h
C
o
n
te
n
t
(%
)
B. Rudiyanto et al Int. J. Renew. Energy Dev 2023, 12(2), 270-276
|274
ISSN: 2252-4940/© 2023. The Author(s). Published by CBIORE
V3 produced the highest ash content with a ratio of coconut
shell to cassava peel adhesive of 65%:35%. In contrast, the
lowest ash content was obtained in V1 at 1.50%, with a ratio of
coconut shell to cassava peel adhesive of 75%:25%. The amount
of adhesive applied can influence the high and low levels of ash
produced (Hasan et al., 2017; Modolo et al., 2015). Ash content
affects the heating value and carbon content. The lower the ash
content, the higher the calorific value and the fixed carbon
content in the briquettes (Lu et al., 2019; Román Gómez,
Cabanzo Hernández, Guerrero, & Mejía-Ospino, 2018; Todaro,
Rita, Cetera, & D’Auria, 2015). In addition, the content of
inorganic materials in adhesives, such as silica (SiO2), MgO,
Fe2O3, A1F3, MgD3, and Fe, can also increase the ash content of
briquettes (Haryanti et al., 2020). Based on these findings, it can
be shown that the ash content increases as the adhesive content
increases. This is similar to Maryono et al. (2013), where the ash
content of coconut shell briquettes increased with cassava peel
adhesive applied.
The higher ash content in briquettes can reduce the calorific
value and combustion rate, preventing air voids from
penetrating the furnace (Sunardi et al., 2019). The maximum
permissible ash content in SNI 01.6235.2000 is 8%, while the ash
content produced in this study ranges from 1.50-2.86%. It shows
that the briquettes produced had good quality. The composition
of the comparison of coconut shell with cassava peel adhesive
is best produced by V1. It has the lowest ash content compared
to other variations. The one-way ANOVA analysis obtained a P-
value <0.05, it can be seen that the composition of coconut shell
charcoal and cassava peel waste affects the ash content results.
Furthermore, in the post hoc Tukey analysis, it is known that the
variations V2 and V3 are not significantly different from each
other, while the variations of V1 are significantly different from
each other with V2 and V3, as shown in Table 7.
3.4 Combustion Rate
Five briquettes were used to heat 700 ml of water using three
iterations of each variation in the combustion rate test to
measure the rate of briquette combustion starting at the speed
of the briquette flame. The calculation of the briquette burning
rate result in this study ranged from 0.021-0.026 gram/s, as
shown in Figure 5.
Fig. 5 Combustion rate of coconut shell briquettes with cassava peel
adhesive
Table 8
Combustion rate analysis using the Tukey method with 95%
confidence
Variation N Mean Grouping
V1 3 0.071000 A
V2 3 0.063000 B
V3 3 0.058000 C
The fastest burning rate is produced by V1 at 0.026 gram/s,
while V3 has the slowest burning rate at 0.021 gram/s. Figure 5
shows that the percentage ratio of the adhesive composition can
affect the rate of combustion produced. This is in line with
Syarief et al. (2021), that the higher the percentage of adhesive
added, the slower the burning rate, and vice versa.
The high percentage of adhesive addition will make the
granules on the briquettes stick firmly. It makes the briquette
pores smaller and difficult for air to enter to speed up the
combustion process. Comparison of the composition of the
variations of the resulting material did not differ much, but the
V1 showed better briquette results than other variations. This is
due to the faster rate of combustion, which makes it easier for
the briquettes to ignite and burn away without producing a lot
of smoke. The V1 shows a more effective and efficient result to
be used as an alternative fuel. The results from the one-way
ANOVA analysis obtained a P-value <0.05. This indicates that
the composition of coconut shell charcoal and cassava peel
waste affects the rate of combustion that occurs in briquettes.
Based on the results of post hoc Tukey analysis, it is known that
the respective variations of V1, V2, and V3 are significantly
different from each other, as shown in Table 8.
3.5 Calorific Value
The calorific value is the main parameter in determining the
quality of briquettes. The calorific value produced in this study
ranged from 6,161 to 6,266 cal/gram. The results of the heat
test using the IKA © 2000 Bomb Calorimeter are shown in
Figure 6.
Figure 6 shows that the highest calorific value produced by
V1 is 6,266 cal/gram, while V3 of 6,161 cal/gram has the lowest
calorific value. The higher the calorific value, the better the
quality of the briquettes (Haryanti et al., 2020). The calorific
value is related to the amount of water and ash in the briquettes.
The percentage of adhesive given influences the amount of
water and ash produced. The higher the adhesive added, the
higher the water and ash produced. Thus, the calorific value
created is low and vice versa (Sulistyaningkarti and Utami,
2017). In this case, the results of the one-way ANOVA analysis
show the P-value >0.05. It can be seen that the composition of
coconut shell charcoal and cassava peel waste does not affect
the resulting calorific value. Based on these results, a post hoc
Tukey analysis is not required.
The minimum standard calorific value of briquettes,
according to SNI 01-6235-2000, is 5,000 cal/gram. However,
the calorific value of briquettes in V1, V2, and V3, as shown in
Figure 6, they have a value of over 5,000 cal/gram. The highest
calorific value was shown by V1 of 6,266 cal/gram with the
coconut shell and cassava peel adhesive ratio at 75%:25%. This
is influenced by the value of water content and ash content.
Moreover, the briquettes produced by V1 offer better quality
than other variations.
Fig. 6 Calorific value of coconut shell briquettes with cassava peel
adhesive
0.071
0.063
0.058
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
V1 (75%:25%) V2 (70%:30%) V3 (65%:35%)
C
o
m
b
u
s
ti
o
n
R
a
te
(g
r
a
m
/s
)
6266
6234
6161
6000
6050
6100
6150
6200
6250
6300
6350
V1 (75%:25%) V2 (70%:30%) V3 (65%:35%)
C
a
lo
r
if
ic
V
a
lu
e
(c
a
l/
g
r
a
m
)
B. Rudiyanto et al Int. J. Renew. Energy Dev 2023, 12(2), 270-276
|275
ISSN: 2252-4940/© 2023. The Author(s). Published by CBIORE
In this study, V1, with a composition of 75% coconut shell and
25% cassava peel adhesive, is the best composition in terms of
4 parameters: density, moisture content, ash content, and
calorific value. This is as a result that applying too much
adhesive can reduce the briquettes' quality. Therefore the
addition of adhesive must be carried out appropriately (Saputra
at. al, 2021). However, the best result for the combustion rate is
sample V2, with a composition of 65%:35%, but this is not very
influential because the difference in the combustion rate
between V1 and V2 has a slight difference.
4. Conclusion
Based on the research results, it can be seen that the use of
coconut shells as raw material for briquettes has an excellent
ability to become a renewable energy source in the form of
biomass. In this case, the percentage variation of adhesive
material such as cassava peel can produce characteristics as fuel
for alternative energy sources. It can be seen that the V1
treatment with a ratio of coconut shell with cassava peel
adhesive of 75%:25% can produce charcoal briquettes that have
better quality than other variations, with a density value of 0.66
gram/cm3, water content of 5.51%, ash content of 1.50%,
combustion rate of 0.026 gram/s and calorific value of 6,266
cal/gram. The one-way ANOVA analysis shows that the
composition of coconut shell charcoal and cassava peel waste
affects the resulting density, moisture content, ash content, and
burning rate. In this case, the heating value is not affected by
variations in the composition of the raw materials. However,
charcoal briquettes from coconut shell waste and natural
adhesives from cassava peel waste are feasible to be used as
alternative fuels because of their economic value, easy to obtain,
abundantly available, and have complied with SNI 01-6235-
2000. Besides, further identification of the starch content in
cassava peel, volatile matter content and carbon content in
briquettes is required to improve research findings and develop
solutions using alternative energy sources with higher quality
and more environmentally friendly. This is because the natural
adhesive content can reduce the calorific value of briquettes.
The addition of adhesive is carried out without a carbonization
process, and it is necessary to analyze the value of volatile
matter and fixed carbon. Considering their ability to marge, it is
important to know the volatile and fixed carbon content.
Moreover, if the volatile content is too high and the fixed carbon
is too low, it will significantly affect the decrease in the heating
value of the briquettes.
Author Contributions: BR; supervision, resources, project
administration, IRA; Conceptualization, original draft, ZU;
methodology, DAP; formal analysis, MH; writing—review and editing,
project administration, BP; supervision, validation, TP: supervision,
validation —. All authors have read and agreed to the published version
of the manuscript.
Conflicts of Interest: The authors declare no conflict of interest.
References
Abyaz, A., Afra, E., & Saraeyan, A. (2020). Improving technical
parameters of biofuel briquettes using cellulosic binders. Energy
Sources, Part A: Recovery, Utilization and Environmental Effects,
00(00), 1–12. https://doi.org/10.1080/15567036.2020.1806955
Adeleke, A. A., Odusote, J. K., Ikubanni, P. P., Olabisi, A. S., & Nzerem,
P. (2022). Briquetting of subbituminous coal and torrefied
biomass using bentonite as inorganic binder. Scientific Reports,
12(1), 1–11. https://doi.org/10.1038/s41598-022-12685-5
Anggraeni, S., Girsang, G. C. S., Nandiyanto, A. B. D., & Bilad, M. R.
(2021). Effects of particle size and composition of
sawdust/carbon from rice husk on the briquette performance.
Journal of Engineering Science and Technology, 16(3), 2298–2311.
Aransiola, E. F., Oyewusi, T. F., Osunbitan, J. A., & Ogunjimi, L. A. O.
(2019). Effect of binder type, binder concentration and
compacting pressure on some physical properties of carbonized
corncob briquette. Energy Reports, 5, 909–918.
https://doi.org/10.1016/j.egyr.2019.07.011
Ardelean, E., Socalici, A., Lupu, O., Bistrian, D., Dobrescu, C., &
Constantin, N. (2022). Recovery of Waste with a High Iron
Content in the Context of the Circular Economy. Materials,
15(14), 1–18. https://doi.org/10.3390/ma15144995
Bazhin, V. Y., Kuskov, V. B., & Kuskova, Y. V. (2019). Processing of low-
demand coal and other carbon-containing materials for energy
production purposes. Inzynieria Mineralna, 2019(1), 195–198.
https://doi.org/10.29227/IM-2019-01-37
BPPT. (2021). Indonesia Energy Outlook 2021: Perspective of Indonesian
Energy Technology - Solar Power for Charging Station Energy
Supply. Jakarta.
Budi Surono, U. (2019). Biomass Utilization of Some Agricultural Wastes
as Alternative Fuel in Indonesia. Journal of Physics: Conference
Series, 1175(1). https://doi.org/10.1088/1742-
6596/1175/1/012271
Cuong, T. T., Le, H. A., Khai, N. M., Hung, P. A., Linh, L. T., Thanh, N.
V., … Huan, N. X. (2021). Renewable energy from biomass
surplus resource: potential of power generation from rice straw
in Vietnam. Scientific Reports, 11(1), 1–10.
https://doi.org/10.1038/s41598-020-80678-3
Dani, S., & Wibawa, A. (2018). Challanges and Policy for Biomass
Energy in Indonesia. International Journal of Business, Economic
and Law, 15(5), 41047. https://www.ijbel.com/wp-
content/uploads/2018/04/IJBEL15_212.pdf
Directorate General of Plantation. (2021). National Leading Plantation
Statistics 2019-2021 (D. Gartina & R. L. L. Sukriya, eds.). Jakarta:
Sekterariat Direktorat Jenderal Perkebunan.
Ganesan, S., & Vedagiri, P. (2022). Production of sustainable biomass
briquettes from de-oiled cashewnut Shell. Materials Today:
Proceedings. https://doi.org/10.1016/j.matpr.2022.09.179
Ghafar, H., Halidi, S. N. A. M., & So’aib, M. S. (2020). Coconut Shell:
Thermogravimetric Analysis and Gross Calorific Value.
Proceedings of Mechanical Engineering Research Day, 206–207.
https://www3.utem.edu.my/care/proceedings/merd20/pdf/0
6_Energy_Engineering_and_Management/089-p206_207.pdf
Guo, Z., Wu, J., Zhang, Y., Wang, F., Guo, Y., Chen, K., & Liu, H. (2020).
Characteristics of biomass charcoal briquettes and pollutant
emission reduction for sulfur and nitrogen during combustion.
Fuel, 272(April), 117632.
https://doi.org/10.1016/j.fuel.2020.117632
Haryanti, N. H., Wardhana, H., & Suryajaya. (2020). Effect of Pressure
on Alaban Charcoal Briquettes Small Particle Size. Jurnal Risalah
Fisika, 4(1), 19–26.
https://doi.org/https://doi.org/10.35895/rf.v4i1.170
Hasan, E. S., Jahiding, M., Mashuni, Ilmawati, W. O. S., Wati, W., &
Sudiana, I. N. (2017). Proximate and the Calorific Value Analysis
of Brown Coal for High-Calorie Hybrid Briquette Application.
Journal of Physics: Conference Series, 846(1).
https://doi.org/10.1088/1742-6596/846/1/012022
Helwani, Z., Ramli, M., Rusyana, A., Marlina, M., Fatra, W., Idroes, G.
M., … Idroes, R. (2020). Alternative briquette material made
from palm stem biomass mediated by glycerol crude of biodiesel
byproducts as a natural adhesive. Processes, 8(7).
https://doi.org/10.3390/pr8070777
Hirniah, F. E. (2020). Energy Analysis in Making Charcoal Briquettes from
Cassava Peel with Tapioca Flour as Adhesive. Universitas Jember,
Jember.
Jiang, X., Wu, C., Zhou, H., Gao, B., Fang, X., Han, J., & Gao, W. (2022).
Relationship between thermal properties and structure,
composition of briquette through grey relational analysis. Journal
of Applied Geophysics, 206(November 2021), 104786.
https://doi.org/10.1016/j.jappgeo.2022.104786
Kabir Ahmad, R., Anwar Sulaiman, S., Yusup, S., Sham Dol, S., Inayat,
M., & Aminu Umar, H. (2022). Exploring the potential of coconut
shell biomass for charcoal production. Ain Shams Engineering
Journal, 13(1), 101499.
https://doi.org/10.1016/j.asej.2021.05.013
Kamunur, K., Ketegenov, T., Kalugin, S., Karagulanova, A., &
Zhaksibaev, M. (2022). The role of the alkaline promoter on the
formation of strength and burning of coal briquettes. South
African Journal of Chemical Engineering, 42(May), 156–161.
https://doi.org/10.1080/15567036.2020.1806955
https://doi.org/10.1038/s41598-022-12685-5
https://doi.org/10.1016/j.egyr.2019.07.011
https://doi.org/10.3390/ma15144995
https://doi.org/10.29227/IM-2019-01-37
https://doi.org/10.1088/1742-6596/1175/1/012271
https://doi.org/10.1088/1742-6596/1175/1/012271
https://doi.org/10.1038/s41598-020-80678-3
https://www.ijbel.com/wp-content/uploads/2018/04/IJBEL15_212.pdf
https://www.ijbel.com/wp-content/uploads/2018/04/IJBEL15_212.pdf
https://doi.org/10.1016/j.matpr.2022.09.179
https://www3.utem.edu.my/care/proceedings/merd20/pdf/06_Energy_Engineering_and_Management/089-p206_207.pdf
https://www3.utem.edu.my/care/proceedings/merd20/pdf/06_Energy_Engineering_and_Management/089-p206_207.pdf
https://doi.org/10.1016/j.fuel.2020.117632
https://doi.org/https:/doi.org/10.35895/rf.v4i1.170
https://doi.org/10.1088/1742-6596/846/1/012022
https://doi.org/10.3390/pr8070777
https://doi.org/10.1016/j.jappgeo.2022.104786
https://doi.org/10.1016/j.asej.2021.05.013
B. Rudiyanto et al Int. J. Renew. Energy Dev 2023, 12(2), 270-276
|276
ISSN: 2252-4940/© 2023. The Author(s). Published by CBIORE
https://doi.org/10.1016/j.sajce.2022.08.009
Karimibavani, B., Sengul, A. B., & Asmatulu, E. (2020). Converting
briquettes of orange and banana peels into carbonaceous
materials for activated sustainable carbon and fuel sources.
Energy, Ecology and Environment, 5(3), 161–170.
https://doi.org/10.1007/s40974-020-00148-4
Kariuki, S. W., Muthengia, J. W., Erastus, M. K., Leonard, G. M., &
Marangu, J. M. (2020). Characterization of composite material
from the copolymerized polyphenolic matrix with treated
cassava peels starch. Heliyon, 6(7), e04574.
https://doi.org/10.1016/j.heliyon.2020.e04574
Kayiwa, R., Kasedde, H., Lubwama, M., & Kirabira, J. B. (2021a).
Characterization and pre-leaching effect on the peels of
predominant cassava varieties in Uganda for production of
activated carbon. Current Research in Green and Sustainable
Chemistry, 4(February), 100083.
https://doi.org/10.1016/j.crgsc.2021.100083
Kayiwa, R., Kasedde, H., Lubwama, M., & Kirabira, J. B. (2021b). The
potential for commercial scale production and application of
activated carbon from cassava peels in Africa: A review (Elsevier
Ltd; Vol. 15). Elsevier Ltd.
https://doi.org/10.1016/j.biteb.2021.100772
Kong, S. H., Loh, S. K., Bachmann, R. T., Rahim, S. A., & Salimon, J.
(2014). Biochar from Oil Palm Biomass: A Review of its Potential
and Challenges. Journal Renewable and Sustainable Energy
Reviews, 39, 729–739.
https://doi.org/10.1016/j.rser.2014.07.107
Lu, Z., Chen, X., Yao, S., Qin, H., Zhang, L., Yao, X., … Lu, J. (2019).
Feasibility study of gross calorific value, carbon content, volatile
matter content and ash content of solid biomass fuel using laser-
induced breakdown spectroscopy. Fuel, 258(September),
116150. https://doi.org/10.1016/j.fuel.2019.116150
Maryono, Sudding, & Rahmawati. (2013). Preparation and Quality
Analysis of Coconut Shell Charcoal Briquette Observed by Starch
Concentration. Journal Chemical, 14(1), 74–83.
Maulina, S., Sarah, M., Misran, E., & Anita, M. F. (2021). The correlation
of ultimate analysis and calorific value on palm oil briquettes
using durian seed adhesives. IOP Conference Series: Materials
Science and Engineering, 1122(1), 012079.
https://doi.org/10.1088/1757-899x/1122/1/012079
Meytij, J. R., Santoso, I. R. S., Rampe, H. L., Tiwow, V. A., & Apita, A.
(2021). Infrared Spectra Patterns of Coconut Shell Charcoal as
Result of Pyrolysis and Acid Activation Origin of Sulawesi,
Indonesia. E3S Web of Conferences, 328, 08008.
https://doi.org/10.1051/e3sconf/202132808008
Ministry of Agriculture. (2021). Agricultural Statistics 2021 (A. A. Susanti
& M. A. Supriyatna, Eds.). Jakarta: Center for Agricultural Data
and Information Systems, Ministry of Agriculture, Republic of
Indonesia.
Modolo, R. C. E., Silva, T., Senff, L., Tarelho, L. A. C., Labrincha, J. A.,
Ferreira, V. M., & Silva, L. (2015). Bottom ash from biomass
combustion in BFB and its use in adhesive-mortars. Fuel
Processing Technology, 129, 192–202.
https://doi.org/10.1016/j.fuproc.2014.09.015
Niño, A., Arzola, N., & Araque, O. (2020). Experimental study on the
mechanical properties of biomass briquettes from a mixture of
rice husk and pine sawdust. Energies, 13(5).
https://doi.org/10.3390/en13051060
Nurhilal, O., Suryaningsih, S., & Indrana, I. (2018). Study of Thermal
Efficiency of Biomass Carbonizing by Direct Method. Journal of
Physics: Conference Series, 1080. https://doi.org/10.1088/1742-
6596/1080/1/012024
Rizal, W. A., Nisa, K., Maryana, R., Prasetyo, D. J., Pratiwi, D., Jatmiko,
T. H., … Suwanto, A. (2020). Chemical composition of liquid
smoke from coconut shell waste produced by SME in Rongkop
Gunungkidul. IOP Conference Series: Earth and Environmental
Science, 462(1). https://doi.org/10.1088/1755-
1315/462/1/012057
Román Gómez, Y., Cabanzo Hernández, R., Guerrero, J. E., & Mejía-
Ospino, E. (2018). FTIR-PAS coupled to partial least squares for
prediction of ash content, volatile matter, fixed carbon and
calorific value of coal. Fuel, 226(April), 536–544.
https://doi.org/10.1016/j.fuel.2018.04.040
Sarkar, J. K., & Wang, Q. (2020). Different Pyrolysis Process Conditions
of South Asian Waste Coconut Shell and Characterization of Gas,
Bio-Char, and Bio-Oil. Energies.
Satya, M., Raju, C. A. I., Praveena, U., & Jyothi, K. R. (2014). Studies on
Development of Fuel Briquettes Using Locally Available Waste.
Journal of Engineering Research and Applications, 4(3), 553–559.
https://www.ijera.com/papers/Vol4_issue3/Version%201/CT
4301553559.pdf
Setter, C., Sanchez Costa, K. L., Pires de Oliveira, T. J., & Farinassi
Mendes, R. (2020). The effects of kraft lignin on the
physicomechanical quality of briquettes produced with
sugarcane bagasse and on the characteristics of the bio-oil
obtained via slow pyrolysis. Fuel Processing Technology,
210(August), 106561.
https://doi.org/10.1016/j.fuproc.2020.106561
Srisang, S., Phetpan, K., Ruttanadech, N., Limmun, W., Youryon, P.,
Kongtragoul, P., … Chungcharoen, T. (2022). Charcoal briquette
production from waste in the coffee production process using
hydrothermal and torrefaction techniques: A comparative study
with carbonization technique. Journal of Cleaner Production,
372(August), 133744.
https://doi.org/10.1016/j.jclepro.2022.133744
Sulistyaningkarti, L., & Utami, B. (2017). Making Charcoal Briquettes
from Corncob Organic Waste Using Variations in Type and
Percentage of Adhesives. Jurnal Kimia Dan Pendidikan Kimia,
2(1), 43–53.
Sunardi, Djuanda, & Mandra, M. A. S. (2019). Characteristics of Charcoal
Briquettes from Agricultural Waste with Compaction Pressure
and Particle Size Variation as Alternative Fuel. International
Energy Journal, 19, 139–148.
Suryaningsih, S., Resitasari, R., & Nurhilal, O. (2019). Analysis of
biomass briquettes based on carbonized rice husk and jatropha
seed waste by using newspaper waste pulp as an adhesive
material. Journal of Physics: Conference Series, 1280(2).
https://doi.org/10.1088/1742-6596/1280/2/022072
Syarief, A., Nugraha, A., Ramadhan, M. N., Fitriyadi, & Supit, G. G.
(2021). Effect of Variation in Composition and Type of Adhesive
on Physical Properties and Burning Characteristics of Alaban
Wood Charcoal Waste Briquettes (Vitex pubescens VAHL) Rice
Husk (Oryza sativa L). Proceedings of the National Wetland
Environment Seminar. Banjarmasin.
Todaro, L., Rita, A., Cetera, P., & D’Auria, M. (2015). Thermal treatment
modifies the calorific value and ash content in some wood
species. Fuel, 140, 1–3.
https://doi.org/10.1016/j.fuel.2014.09.060
Tu, W., Liu, Y., Xie, Z., Chen, M., Ma, L., Du, G., & Zhu, M. (2021). A
novel activation-hydrochar via hydrothermal carbonization and
KOH activation of sewage sludge and coconut shell for biomass
wastes: Preparation, characterization and adsorption properties.
Journal of Colloid and Interface Science, 593, 390–407.
https://doi.org/10.1016/j.jcis.2021.02.133
Tzelepi, V., Zeneli, M., Kourkoumpas, D. S., Karampinis, E., Gypakis, A.,
Nikolopoulos, N., & Grammelis, P. (2020). Biomass availability in
europe as an alternative fuel for full conversion of lignite power
plants: A critical review. Energies, 13(13).
https://doi.org/10.3390/en13133390
Vaish, S., Sharma, N. K., & Kaur, G. (2022). A review on various types of
densification/briquetting technologies of biomass residues. IOP
Conference Series: Materials Science and Engineering, 1228(1),
012019. https://doi.org/10.1088/1757-899x/1228/1/012019
Velusamy, S., Subbaiyan, A., Kandasamy, S., Shanmugamoorthi, M., &
Thirumoorthy, P. (2022). Combustion characteristics of biomass
fuel briquettes from onion peels and tamarind shells. Archives of
Environmental and Occupational Health, 77(3), 251–262.
https://doi.org/10.1080/19338244.2021.1936437
Yana, S., Nizar, M., Irhamni, & Mulyati, D. (2022). Biomass waste as a
renewable energy in developing bio-based economies in
Indonesia: A review. Renewable and Sustainable Energy Reviews,
160(5), 112268. https://doi.org/10.1016/j.rser.2022.112268
© 2023. The Author(s). This article is an open access article distributed under the terms and conditions of the Creative Commons
Attribution-ShareAlike 4.0 (CC BY-SA) International License (http://creativecommons.org/licenses/by-sa/4.0/)
https://doi.org/10.1016/j.sajce.2022.08.009
https://doi.org/10.1007/s40974-020-00148-4
https://doi.org/10.1016/j.heliyon.2020.e04574
https://doi.org/10.1016/j.crgsc.2021.100083
https://doi.org/10.1016/j.biteb.2021.100772
https://doi.org/10.1016/j.rser.2014.07.107
https://doi.org/10.1016/j.fuel.2019.116150
https://doi.org/10.1088/1757-899x/1122/1/012079
https://doi.org/10.1051/e3sconf/202132808008
https://doi.org/10.1016/j.fuproc.2014.09.015
https://doi.org/10.3390/en13051060
https://doi.org/10.1088/1742-6596/1080/1/012024
https://doi.org/10.1088/1742-6596/1080/1/012024
https://doi.org/10.1088/1755-1315/462/1/012057
https://doi.org/10.1088/1755-1315/462/1/012057
https://doi.org/10.1016/j.fuel.2018.04.040
https://www.ijera.com/papers/Vol4_issue3/Version%201/CT4301553559.pdf
https://www.ijera.com/papers/Vol4_issue3/Version%201/CT4301553559.pdf
https://doi.org/10.1016/j.fuproc.2020.106561
https://doi.org/10.1016/j.jclepro.2022.133744
https://doi.org/10.1088/1742-6596/1280/2/022072
https://doi.org/10.1016/j.fuel.2014.09.060
https://doi.org/10.1016/j.jcis.2021.02.133
https://doi.org/10.3390/en13133390
https://doi.org/10.1088/1757-899x/1228/1/012019
https://doi.org/10.1080/19338244.2021.1936437
https://doi.org/10.1016/j.rser.2022.112268