Article

Valorization of Oil Palm Empty Fruit Bunches into Sulfonated Carbon

Catalysts for Esterification of Vegetable Oil

Gimelliya Saragih^1*

, Vivi Purwandari², Nelson Silitonga³, Abdillah⁴, Yenny

Sitanggang⁵, Liver Zai⁶, Mukhtissiarni⁷

^1,5Department of Chemical Engineering, Politeknik Teknologi Kimia Industri, Jl. Medan Tenggara VII,

Medan 20228, Indonesia

^2,6,7Department of Chemistry, Universitas Sari Mutiara Indonesia, Jalan Kapten Muslim No.79,

Medan 20123, Indonesia

^3,4Department of Mechanical Engineering, Politeknik Teknologi Kimia Industri, Jl. Medan Tenggara

VII, Medan 20228, Indonesia

Abstract

This study reports the synthesis, characterization, and catalytic evaluation of sulfonated carbon derived

from oil palm empty fruit bunches (OPEFB) for biodiesel production. Activated carbon produced through

controlled pyrolysis was sulfonated using sulfuric acid concentrations of 7%, 10%, and 13% to examine

the influence of acid strength on catalyst properties. The materials were characterized using TGA/DTA,

FTIR, BET, and SEM to assess thermal stability, functional group incorporation, surface morphology, and

porosity. Among the prepared samples, the catalyst treated with 10% H₂SO₄ (SA-10) exhibited the most

favorable combination of surface area, pore accessibility, and –SO₃H density. Esterification of waste

cooking oil (WCO) at 65 °C for 2 h demonstrated that SA-10 achieved the highest ester yield (43.28%) at

a catalyst loading of 3 g, outperforming samples with insufficient or excessive sulfonation. These findings

highlight the potential of OPEFB as a sustainable precursor for solid acid catalyst development and

emphasize the importance of optimizing sulfonation conditions to enhance catalytic performance.

Further studies on catalyst reusability, kinetic behavior, and techno-economic feasibility are

recommended to support industrial-scale application.

Keywords: Esterification; Functional material; Heterogeneous catalyst; Sulfonated carbon

*

Corresponding author

Email address: gimelliya@ptki.ac.id

DOI: https://doi.org/10.22437/chp.v9i2.47630

Received August 05^th2025; Accepted November 25^th2025; Available online December 19^th2025

(https://creativecommons.org/licenses/by/4.0 )

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Chempublish Journal, 9(2) 2025, 287-299

Graphical Abstract

Introduction

based catalysts have shown notable promise

due to their strong Brønsted acidity, thermal

stability, and reusability, as highlighted by

Chong et al. (2021) [16].

Growing

concerns

over

environmental

degradation and the depletion of fossil-

based resources have accelerated the

development

technologies [1–2]. Biodiesel, derived from

biomass-based materials, has received

of

renewable

energy

Agricultural residues such as oil palm empty

fruit bunches (OPEFB) represent attractive

precursors for carbon-based catalysts owing

to their high carbon content [17], intrinsic

porosity [18], and wide availability in palm-

considerable attention as a biodegradable

and environmentally sustainable substitute

for petroleum-derived diesel [3–5]. Waste

cooking oil (WCO), in particular, is an

abundant and low-cost feedstock [6–8] with

a high free fatty acid (FFA) content, offering

both economic benefits and opportunities

for sustainable waste valorization [9–10].

oil–producing

pyrolysis of OPEFB produces activated

carbon with favorable structural

regions

[19].

Controlled

characteristics [20–22], while subsequent

sulfonation using sulfuric acid introduces –

SO₃H groups that impart strong acidity

suitable for esterification reactions [23–24].

Traditional

commonly

esterification

employ homogeneous

processes

acid

The

physicochemical

characteristics

of

catalysts such as sulfuric acid; however, their

use is associated with several drawbacks,

sulfonated carbon—including surface area,

thermal stability, pore morphology, and acid

site density—are strongly influenced by the

sulfonation conditions and the chemical

nature of the precursor [25–26]. Although

including

equipment

complex

catalyst

and

separation,

adverse

corrosion,

environmental impacts [11–13]. As a result,

heterogeneous solid acid catalysts have

emerged as more sustainable alternatives

[14–15]. Among them, sulfonated carbon-

earlier

sulfonation of various biomass sources such

as glucose, starch, and lignocellulosic

studies

have

examined

the

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Chempublish Journal, 9(2) 2025, 287-299

materials [27–28], systematic investigations

cool naturally to room temperature and was

stored in a desiccator prior to use.

specifically

targeting

OPEFB-derived

sulfonated

carbon remain

limited. In

Sulfonation of Activated Carbon.

particular, there is a lack of comprehensive

studies evaluating how variations in sulfuric

acid concentration influence both the

structural attributes of the catalyst and its

catalytic performance.

Activated carbon produced from pyrolysis

was sulfonated using sulfuric acid solutions

of 7%, 10%, and 13% (w/w), prepared by

diluting concentrated H₂SO₄ (98%) with

deionized water. A carbon-to-acid mass ratio

of 1:10 was applied. The mixture was placed

in a 250-mL three-neck round-bottom flask

equipped with a reflux condenser and

positioned in a temperature-controlled oil

bath inside a fume hood to ensure safe

handling of potential SO₂ vapors. The

reaction system remained closed but not

pressurized to minimize acid loss during

heating.

To address this gap, the present work

synthesizes sulfonated carbon catalysts

from OPEFB using controlled sulfuric acid

concentrations (7%, 10%, and 13%) and

evaluates their catalytic performance in the

esterification of waste cooking oil (WCO)

under mild reaction conditions. The novelty

of this study lies in the utilization of OPEFB

as a sustainable precursor, the application of

mild sulfonation strategies, and a systematic

assessment

properties to catalytic behavior. This study

offers new insights into the relationship

that

links

physicochemical

Sulfonation was performed at 150 °C for 6 h

under continuous magnetic stirring (400

rpm) to ensure uniform interaction between

the carbon matrix and the acid. After

completion, the mixture was cooled to room

between

sulfonation

degree,

catalyst

structure, and biodiesel yield, thereby

addressing an important gap in the existing

literature.

temperature,

washed

repeatedly

with

deionized water until neutral pH was

achieved, and dried at 105 °C for 24 h.

Materials and Methods

For clarity, samples are labeled according to

their treatment conditions. CA denotes the

activated carbon obtained from pyrolysis

without sulfonation. SA-7, SA-10, and SA-13

represent carbon sulfonated with 7%, 10%,

Synthesis of Carbon Material from Oil Palm

Biomass (OPEFB)

OPEFB obtained from PT. Gergas Utama,

Langkat was first washed to remove dirt and

impurities and then sun-dried. The dried

biomass was further dehydrated in an oven

at 105 °C for 24 h to eliminate residual

bound moisture. The dried and shredded

OPEFB was subsequently subjected to

pyrolysis at 500–700 °C [27] for a fixed

residence time of 2 h [28], a duration

selected to ensure adequate carbonization

and promote stable pore development

without inducing structural collapse. The

resulting activated carbon was allowed to

and

materials

structural,

13%

H₂SO₄,

were subjected

and

respectively.

These

thermal,

to

morphological

characterization (TGA/DTA, FTIR, BET, and

SEM) to assess the influence of sulfonation

conditions

on

their

physicochemical

properties.

Esterification Procedure.

Esterification was conducted using waste

cooking oil (WCO) as the feedstock. The WCO

was weighed, placed in a three-neck flask

equipped with a condenser, and preheated

289

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Chempublish Journal, 9(2) 2025, 287-299

to 65 °C to avoid methanol evaporation.

Methanol was added according to the

Result and Discussion

As the WCO was used in its as-received

condition, its composition likely reflects the

typical characteristics of recycled frying oils

predetermined

stoichiometric

ratio,

followed by the addition of the sulfonated

carbon catalyst (0 g, 3 g, or 5 g depending on

the experiment).

reported

in

the

literature.

Such

oils

commonly contain 3–15% free fatty acids

(FFA), which promote water formation

during esterification and subsequently shift

The reaction mixture was refluxed at 65 °C

for 2 h under continuous magnetic stirring.

This reaction time is widely reported as

sufficient for effective esterification and to

promote proper mass transfer among

methanol, the oil phase, and the solid

catalyst. Maintaining stirring throughout the

reaction also prevents catalyst settling and

the

reaction

equilibrium

toward

the

reactants under mild conditions. Residual

moisture content generally 0.2–1.5% further

suppresses ester conversion by hydrolyzing

methyl

esters

and

inhibiting

proton-

catalyzed reactions. In addition, WCO is

typically dominated by long-chain fatty acids,

particularly oleic and palmitic acids, which

enhances

catalytic

contact,

thereby

improving conversion efficiency [11].

esterify

more

slowly

at

atmospheric

After reaction, the mixture was allowed to

settle into two layers: an upper biodiesel

layer and a lower glycerin-rich phase

containing residual catalyst. The biodiesel

layer was separated using a separatory

funnel, washed with warm water to remove

remaining methanol and catalyst residues,

and dried using anhydrous sodium sulfate

(Na₂SO₄). The final biodiesel product was

analyzed by FTIR to confirm ester functional

group formation.

pressure due to steric hindrance and mass-

transfer limitations [6–10]. These inherent

characteristics of WCO help explain the

moderate ester yield obtained in this study

and align with previous findings indicating

that high-FFA feedstocks often require either

intensified reaction conditions or catalysts

with higher pore accessibility to achieve

conversion levels above 70%.

The sulfonated carbon samples synthesized

in

this

work

exhibited

characteristics

distinct

that

Characterization Techniques.

physicochemical

reflected the influence of sulfuric acid

concentration during treatment. All carbon

materials (CA, SA-7, SA-10, and SA-13) were

Comprehensive

performed on both activated and sulfonated

carbon samples. FTIR spectra were recorded

characterization

was

comprehensively

characterized

using

a

Shimadzu

IR-Prestige

21

TGA/DTA to evaluate thermal stability, FTIR

to identify functional groups, SEM to observe

surface morphology, and BET analysis to

determine surface area and porosity. These

spectrophotometer to identify characteristic

functional groups, particularly to confirm the

presence of –SO₃H functionalities and to

verify ester formation in biodiesel. Surface

morphology was examined using SEM

imaging with a Bruker instrument. Surface

area and porosity were evaluated through

BET analysis using a Quantachrome system.

analyses

collectively

confirmed

the

structural

and chemical

modifications

induced by sulfonation.

Thermal Stability (TGA/DTA Analysis)

Thermal

stability

and

decomposition

behavior were assessed using TGA/DTA with

an STA TG/DTA 7300 analyzer.

The thermal behavior of the activated and

sulfonated carbons was evaluated using TGA

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and DTA, as illustrated in Figure 1. The TGA

curves exhibited multistage weight-loss

patterns corresponding to (i) moisture

evaporation, (ii) decomposition of oxygen-

containing surface functionalities, and (iii)

final degradation of the carbon matrix.

Among the samples, SA-10 retained the

smoother and more gradual decomposition

profile, indicative of thermally stable sulfonic

and carbonaceous structures. In contrast,

SA-7 exhibited sharper exothermic events,

suggesting the presence of less stable –SO₃H

groups and weaker surface functionalities.

These trends align with the sulfonation

conditions applied during synthesis, as

variations in acid concentration strongly

highest

residual

mass,

confirming

its

superior thermal stability and more robust

carbon framework relative to SA-7 and SA-13

[29].

influence

the

stability

and

bonding

environment of –SO₃H moieties on carbon

surfaces [30].

The DTA curves provided additional insight

into thermal transitions. SA-10 showed a

Figure 1. TGA and DTA curves of CA, SA-7, SA-10, and SA-13 showing mass loss and thermal

transitions associated with pyrolysis and sulfonation. Measurements were conducted under

nitrogen flow at a heating rate of 10 °C/min.

Functional Group Analysis (FTIR)

samples,

SA-10

exhibited

the

highest

intensity in this region, indicating an optimal

degree of sulfonation without excessive

blocking of pore structures [24].

FTIR analysis (Fig. 2a) was conducted to

evaluate the chemical modifications induced

by sulfonation. All sulfonated samples (SA-7,

SA-10, and SA-13) displayed characteristic

absorption bands in the 1040–1150 cm⁻¹

region corresponding to S=O and S–O

stretching vibrations, which were absent in

the untreated activated carbon (CA). These

bands confirm the successful incorporation

of –SO₃H groups onto the carbon surface,

In addition to the appearance of sulfonic

bands, minor peak shifts of approximately

5–10 cm⁻¹ were observed in the aromatic

C=C region near ~1600 cm⁻¹ and the C–O

stretching region (1000–1200 cm⁻¹). These

shifts reflect alterations in the electronic

environment of the carbon framework due

to the grafting of electron-withdrawing –

SO₃H groups [31]. Furthermore, the broad

O–H stretching band between 3000–3600

consistent

sulfonated

materials

with

biomass-derived

[29–30]. Among the

on

carbon

tested

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Chempublish Journal, 9(2) 2025, 287-299

cm⁻¹ intensified in all sulfonated samples,

indicating the presence of acidic hydroxyl

groups and enhanced surface hydrophilicity,

a feature commonly reported in sulfonated

lignocellulosic carbons [32]

Figure 2. FTIR Spectra of sulfonated carbon and esterification products

The FTIR spectrum of the esterification

product also revealed a strong absorption at

~1740 cm⁻¹, attributed to the C=O stretching

vibration of methyl esters, confirming the

successful conversion of fatty acids into

biodiesel [32].

Upon sulfonation, distinct changes in surface

morphology were observed. The SA-7

sample retained relatively large and open

pores, indicating that low acid concentration

induced only mild surface modification. This

behavior is consistent with observations by

García-Bordejé et al. (2021), who reported

Taken together, the emergence of S-

containing functional bands, the systematic

increase in peak intensities, the observed

that

insufficient

sulfonating

strength

generally leads to partial functionalization

while preserving most of the native pore

network [29].

band

broadening

shifts,

and

collectively

the

enhanced

provide

O–H

strong

evidence for the successful grafting of –SO₃H

groups onto OPEFB-derived activated

carbon and corroborate the structural

In contrast, SA-10 displayed a moderately

smoother surface with well-defined and

uniformly distributed pores, suggesting an

optimal degree of sulfonation that enhances

surface functionalization while maintaining

structural integrity. Similar morphological

evolution has been reported by Yadav et al.

transformations

sulfonation.

predicted

during

Surface Morphology (SEM Analysis)

(2023),

who

found

that

moderate

SEM imaging (Figure 3) provided clear

insights into the morphological evolution of

the carbon materials following sulfonation.

The raw activated carbon (CA) exhibited a

rough, irregular surface with abundant and

well-developed pores, typical of carbonized

sulfonation produces a balanced carbon

structure—adequately functionalized but

not overly compact—resulting in improved

catalytic performance [30]. This balance

between pore accessibility and functional

group density aligns with the favorable

physicochemical characteristics of SA-10.

lignocellulosic

biomass.

This

structure

reflects the inherent porosity generated

during pyrolysis of OPEFB.

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Chempublish Journal, 9(2) 2025, 287-299

Meanwhile, SA-13 exhibited clear signs of

sulfonation compromises surface area and

reduces reactant accessibility. Overall, the

partial

compaction,

sulfonation.

pore

collapse

likely caused

Excessive acid

and

surface

over-

treatment

by

SEM

sulfonation

synthesis.

observations

directly

intensities applied

Among the samples, SA-10

reflect

the

during

introduces a high density of –SO₃H groups

that can obstruct or block pore entrances. Al-

Hamamre et al. (2025) similarly reported

that strong acid loading tends to degrade

carbon microstructures and reduce porosity

due to excessive functional group deposition

exhibits the most favorable structural

features, supporting the superior catalytic

activity observed during esterification. These

morphological

trends

reinforce

the

importance of achieving an optimal balance

between pore structure and functional

group incorporation to maximize catalytic

efficiency.

[24].

observed

mechanism,

The

morphological

deterioration

in

SA-13

indicating

corroborates this

that

excessive

Figure 3. SEM micrographs of (a) CA, (b) SA-7, (c) SA-10, and (d) SA-13, captured at ×1000

magnification and 15 kV accelerating voltage. Scale bars represent 10 µm. Images reveal

changes in pore morphology and surface texture resulting from different H₂SO₄

concentrations.

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Chempublish Journal, 9(2) 2025, 287-299

Surface Area and Porosity (BET Analysis)

[17,22,27]. Following sulfonation, the surface

area and pore volume decreased across all

samples—most notably in SA-7 (34.147 m²/g)

and SA-13 (37.401 m²/g)—due to partial pore

blockage caused by the deposition of –SO₃H

functional groups. This reduction aligns with

findings by García-Bordejé et al. (2021) and

Yadav et al. (2023), who reported that

sulfonation often narrows pore channels

and limits nitrogen adsorption capacity in

biomass-derived carbons [29–30].

BET analysis (Fig. 4 and Table 1) showed that

sulfonation substantially altered the textural

properties of the carbon materials. The

untreated activated carbon (CA) exhibited

the highest BET surface area (50.202 m²/g)

and pore volume (0.071 cm³/g), values

consistent with previously reported ranges

for

OPEFB-derived

activated

carbons

produced under similar pyrolysis conditions

Table 1. BET Surface Area and C Constants of CA and Sulfonated Carbon Samples

Sample

BET Surface Area (m²/g)

Pore Volume (cm³/g)

C Constant

CA

50.202

34.147

41.895

37.401

0.071

0.061

0.066

0.052

122.47

124.05

92.171

745.32

SA-7

SA-10

SA-13

Among the sulfonated samples, SA-10

retained the most favorable structural

profile, with a relatively high surface area

(41.895 m²/g) and pore volume (0.066 cm³/g),

while maintaining a moderate C constant

(92.171). This indicates an optimal balance

between functional group incorporation and

pore preservation, a behavior also noted by

shown in Fig. 4, SA-10 delivered the highest

ester yield (43.28%) at a catalyst loading of 3

g, confirming its superior performance

among the synthesized catalysts. Although

this yield is lower than the 70–95% often

reported in the literature for sulfonated

carbon

emphasize that such high yields are typically

achieved under considerably harsher

conditions—higher methanol-to-oil ratios,

elevated temperatures (70–120 °C),

catalysts,

it

is

important

to

Al-Hamamre

demonstrated that moderate sulfonation

maximizes catalytic accessibility while

avoiding pore collapse [24]. Thus, the

textural integrity of SA-10 supports

et

al.

(2025),

who

extended reaction times, or catalysts with

greater acidity and pore volume [24, 29–30].

In contrast, the present study deliberately

employed mild, energy-efficient conditions,

under which lower yields are not only

expected but also widely documented in

studies using high-FFA feedstocks [6–10].

enhanced diffusion and active-site exposure,

explaining its superior catalytic performance

during esterification compared to the under-

sulfonated (SA-7) and over-sulfonated (SA-

13) materials.

Moreover, the intrinsic properties of WCO

significantly influence the reaction outcome.

High FFA and moisture contents are known

to generate water during esterification,

shifting the reaction equilibrium backward

and suppressing conversion, particularly

under atmospheric pressure [6–9]. Thus, the

Catalyst Dosage Effect

The following figure shows the impact of

catalyst dosage on methyl ester conversion

The catalytic activity of the sulfonated

carbon materials was evaluated through the

esterification of WCO at 65 °C for 2 h. As

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G. Saragih., et al.

Chempublish Journal, 9(2) 2025, 287-299

moderate

mechanistically

yield

obtained

consistent

here

with

is

the

slurry viscosity, and restricts diffusion

between the methanol and oil phases—

composition of the feedstock and the

reaction environment.

limitations

extensively

reported

for

heterogeneous solid acid systems [29–30].

Therefore, the yield decrease is not an

anomaly but a predictable mass-transfer

phenomenon consistent with established

heterogeneous catalysis theory.

The reduction in yield at 5 g catalyst loading

(30.32%) further strengthens the internal

consistency of the results. Excess catalyst

mass promotes agglomeration, increases

Figure 4. FTIR spectra of CA, SA-7, SA-10, and SA-13 showing characteristic bands of –SO₃H

groups (1040–1150 cm⁻¹), C–O stretching, and carbonaceous backbone vibrations

Crucially, the catalytic performance trends

are fully supported by the structural

characteristics obtained from FTIR analysis

(Fig. 4). SA-10 exhibits the strongest S=O and

S–O stretching bands, confirming effective –

Collectively, these results demonstrate that

SA-10 performs exactly as expected for a

catalyst

sulfonation and mild reaction conditions,

providing scientifically justified and

optimized

under

moderate

a

SO₃H

compromising

functionalization

without

carbon

internally coherent explanation for the

observed activity.

the underlying

framework. This optimal balance of acidity

and pore accessibility is precisely the

Conclusion

condition

catalytic

associated with

efficiency in biomass-derived

the highest

This study presents a novel utilization of

OPEFB as a sustainable precursor for

synthesizing sulfonated carbon catalysts and

sulfonated carbons [24, 29–30]. Conversely,

SA-7 shows weaker sulfonic signatures

(under-functionalization),

exhibits spectral indicators

functionalization and pore constriction—

both mechanisms known to suppress

performance.

establishes

a

clear

structure–property

while

of

SA-13

over-

relationship governed by sulfuric acid

concentration. The catalyst prepared with

10% H₂SO₄ (SA-10) exhibited the most

favorable integration of porosity and acid-

site density, enabling superior esterification

performance

under

mild

operating

conditions. These findings underscore the

295

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Chempublish Journal, 9(2) 2025, 287-299

countries. Geoscience frontiers. 2024

potential of OPEFB-derived catalysts as a

viable and resource-efficient platform for

the valorization of high-FFA waste oils. To

advance the practical applicability of this

system, future research should focus on

catalyst regeneration, long-term stability,

kinetic modeling, and rigorous techno-

economic evaluation.

Mar

1;15(2):101757.

DOI:

10.1016/j.gsf.2023.101757

[2]. Yi S, Abbasi KR, Hussain K, Albaker A,

Alvarado R. Environmental concerns in

the United States: can renewable

energy, fossil fuel energy, and natural

resources depletion help?. Gondwana

Research. 2023 May 1;117:41-55. DOI:

10.1016/j.gr.2022.12.021

Acknowledgement

[3]. Mori R. Replacing all petroleum-based

This research is supported by the Industrial

Human Resources Development Agency

(BPSDMI) of the Ministry of Industry of the

Republic of Indonesia through collaborative

research between the Politeknik Teknologi

Kimia Industri Medan and Universitas Sari

Mutiara Indonesia.

chemical

products

with

natural

biomass-based chemical products: a

tutorial review. RSC Sustainability.

2023;1(2):179-212.

DOI: 10.1039/D2SU00014H

[4]. Jaiswal KK, Chowdhury CR, Dutta S,

Banerjee I, Jaiswal KS, Nisansala HM,

Sangmesh B, Sirimuthu NM. Synthesis

of renewable diesel as a substitute for

fossil fuels. InRenewable Diesel 2024

Author Contributions

Conceptualization,

G.S

and

V.P;

methodology, G.S; formal analysis, N.S;

Investigation, N.S; resources, A.A; data

Jan

1

(pp.

1-31).

Elsevier.

DOI:

10.1016/B978-0-323-91153-5.00001-7

[5]. Lee JY, Lee SE, Lee DW. Current status

and future prospects of biological

routes to bio-based products using raw

materials, wastes, and residues as

renewable resources. Critical Reviews

curation

N.S;

writing

original

draft

preparation, G.S; writing, review and editing,

V.P; visualization, A.A; supervision, V.P;

Project administration, G.S; experimental set

up, L.Z; instrumentation, L.Z; literatur review,

M.M.

in

Environmental

Science

and

Technology. 2022 Jul 18;52(14):2453-

Conflict of Interest

509.

DOI:

10.1080/10643389.2021.1880259

The authors declare that there is no conflict

of interest regarding the publication of this

paper.

[6]. Foo WH, Koay SS, Chia SR, Chia WY,

Tang DY, Nomanbhay S, Chew KW.

Recent advances in the conversion of

waste cooking oil into value-added

products: A review. Fuel. 2022 Sep

Ethical Standards

15;324:124539.

10.1016/j.fuel.2022.124539

DOI:

This article does not contain any studies

involving human or animal subjects.

[7]. Manikandan G, Kanna PR, Taler D,

Sobota T. Review of waste cooking oil

(WCO) as a Feedstock for Biofuel—

Indian perspective. Energies. 2023 Feb

References

[1]. Wang J, Azam W. Natural resource

scarcity,

consumption, and total greenhouse

gas emissions in top emitting

fossil

fuel

energy

9;16(4):1739.

DOI:

10.3390/en16041739

296

G. Saragih., et al.

Chempublish Journal, 9(2) 2025, 287-299

[8]. Nascimento L, Ribeiro A, Ferreira A,

Valério N, Pinheiro V, Araújo J, Vilarinho

C, Carvalho J. Turning waste cooking

[14]. Esmi F, Borugadda VB, Dalai AK.

Heteropoly acids as supported solid

acid catalysts for sustainable biodiesel

production using vegetable oils: A

review. Catalysis Today. 2022 Nov

oils

Technologies: A review. Energies. 2021

Dec 24;15(1):116. DOI:

10.3390/en15010116

[9]. Ghosh N, Patra M, Halder G. Current

advances and future outlook of

heterogeneous catalytic

into

biofuels—Valorization

15;404:19-34.

DOI:

10.1016/j.cattod.2022.01.019

[15]. Munyentwali A, Li H, Yang Q. Review of

advances in bifunctional solid

acid/base catalysts for sustainable

biodiesel production. Applied Catalysis

A: General. 2022 Mar 5;633:118525.

DOI: 10.1016/j.apcata.2022.118525

transesterification towards biodiesel

production from waste cooking oil.

Sustainable Energy & Fuels. 2024. DOI :

10.1039/D3SE01564E

[16]. Chong, C. C., Cheng, Y. W., Lam, M. K.,

Setiabudi, H. D., & Vo, D. V. N. (2021).

State‐of‐the‐Art of the Synthesis and

Applications of Sulfonated Carbon‐

[10]. Foo WH, Koay SS, Tang DY, Chia WY,

Chew KW, Show PL. Safety control of

waste cooking oil: transforming hazard

into

available

multifarious

products

with

Based

Production:

Technology, 9(9),

10.1002/ente.202100303

Catalysts

for

Review. Energy

2100303. DOI:

Biodiesel

pre-treatment

processes.

A

Food Materials Research. 2022;2(1):1-

1. DOI: 10.48130/FMR-2022-0001

[11]. Bekhradinassab

E,

Haghighi

M,

[17]. Zakaria NZ, Rozali S, Mubarak NM,

Ibrahim S. A review of the recent trend

Shabani M. A review on acidic metal

oxide-based

heterogeneous

materials

catalytic

towards

biodiesel

in

the

synthesis

of

carbon

nanomaterials derived from oil palm

production via esterification process.

Fuel. 2025 Jan 1;379:132986. DOI:

10.1016/j.fuel.2024.132986

by-product

Conversion

Jan;14(1):13-44. DOI: 10.1007/s13399-

022-02430-3

materials.

and Biorefinery. 2024

Biomass

[12]. Vitiello R, Taddeo F, Russo V, Turco R,

Buonerba A, Grassi A, Di Serio M,

Tesser R. Production of sustainable

[18]. Triana Y, Efriana S, Pratama R, Anjani

SW, Tominaga M, Kurniawan F, Astuti

biochemicals

esterification

heterogeneous

ChemEngineering. 2021 Aug 7;5(3):46.

DOI:

by

reaction

acid

means

of

and

W,

Characterization of Oil Palm Empty

Fruit Bunch‐Activated Carbon for

Battery Electrodes. Energy Storage.

2025 Apr;7(3):e70159.

DOI: 10.1002/est2.70159

[19]. Harahap M, Perangin-Angin

Ismail

AI.

Synthesis

and

catalysts.

10.3390/chemengineering5030046

[13]. Qu R, Junge K, Beller M. Hydrogenation

of carboxylic acids, esters, and related

YA,

Purwandari V, Goei R, Gea S. Acetylated

compounds

catalysts: a step toward sustainable

and carbon-neutral processes.

Chemical Reviews.

over

heterogeneous

lignin from oil palm empty fruit

bunches

and

its

electrospun

nanofibres with PVA: Potential carbon

fibre precursor. Heliyon. 2023 Mar

2023

Jan

5;123(3):1103-65.

10.1021/acs.chemrev.2c00550

DOI:

1;9(3).

DOI:

10.1016/j.heliyon.2023.e14556

297

G. Saragih., et al.

Chempublish Journal, 9(2) 2025, 287-299

[20]. Chitraningrum N, Gunawan F, Farma R,

Subyakto S, Subhan A, Fudholi A, Rajani

A, Apriyani I, Manurung KS, Ramadhan

FA, Fauzi AA. Nitrogen-doped activated

carbon derived from oil palm empty

fruit bunch (OPEFB) for sustainable

biodiesel production: A review. Energy

conversion and management. 2021

Feb

1;229:113760.

DOI:

10.1016/j.enconman.2020.113760

[26]. Shu, D., Zhang, J., Ruan, R., Lei, H.,

Wang, Y., Moriko, Q., ... & Dai, L. (2024).

Insights into preparation methods and

lithium-ion

Conversion

battery.

and Biorefinery. 2025

Biomass

functions

acids. Molecules, 29(1),

10.3390/molecules29010247

of

carbon-based

solid

DOI:

May;15(9):13845-60.

DOI:

247.

10.1007/s13399-024-06220-x

[21]. Pangestu Utomo YM, Risnawati R,

Rohimsyah FM, Tominaga M,

[27]. Elnour, A. Y., Alghyamah, A. A., Shaikh,

H. M., Poulose, A. M., Al-Zahrani, S. M.,

Anis, A., & Al-Wabel, M. I. (2019). Effect

of pyrolysis temperature on biochar

Kurniawan F, Astuti W, Ismail AI, Triana

Y. Oil Palm Empty Fruit Bunch (OPEFB)

Activated

Carbon

as

Promising

microstructural

evolution,

Electrode Materials for Battery. Solid

State Phenomena. 2024 Dec 31;

368:61-76. DOI: 10.4028/p-fDu5JK

physicochemical characteristics, and

its influence on biochar/polypropylene

composites. Applied

sciences, 9(6),

[22]. Zakaria MR, Farid MA, Andou Y, Ramli I,

1149. DOI: 10.3390/app9061149

[28]. Sun, J., He, F., Pan, Y., & Zhang, Z.

(2016). Effects of pyrolysis temperature

Hassan MA. Production of biochar and

activated

carbon

from

oil

palm

biomass: current status, prospects,

and challenges. Industrial Crops and

Products. 2023 Sep 1;199:116767. DOI:

10.1016/j.indcrop.2023.116767

and

physicochemical

different

Agriculturae Scandinavica, Section B —

Soil Plant Science, 67(1), 12–22.

https://doi.org/10.1080/09064710.201

6.1214745

residence

time

properties

on

of

biochar

types. Acta

[23]. Zhang B, Gao M, Tang W, Wang X, Wu

C, Wang Q, Cheung SM, Chen X.

Esterification efficiency improvement

of carbon-based solid acid catalysts

induced by biomass pretreatments:

Intrinsic mechanism. Energy. 2023 Jan

&

[29]. García-Bordejé E, Pires E, Fraile JM.

Carbon materials functionalized with

sulfonic groups as acid catalysts.

15;263:125606.

10.1016/j.energy.2022.125606

[24]. Al-Hamamre Z, Altarawneh I, Alnaief M,

DOI:

InEmerging

catalysis 2021 Jan 1 (pp. 255-298).

Elsevier. DOI: 10.1016/B978-0-12-

817561-3.00008-1

Carbon

materials

for

Sandouqa A, Alhammouri R.

Preparation of sulfonated lignin-based

carbon aerogel catalyst for biodiesel

production from waste vegetable oil.

International Journal of Green Energy.

[30]. Yadav N, Yadav G, Ahmaruzzaman M.

Biomass‐derived sulfonated polycyclic

aromatic carbon catalysts for biodiesel

production by esterification reaction.

Biofuels, bioproducts and biorefining.

2025 May 19;22(7):1267-84.

10.1080/15435075.2024.2429776

DOI:

2023

Sep;17(5):1343-67.

DOI:

[25]. Ma X, Liu F, Helian Y, Li C, Wu Z, Li H,

Chu H, Wang Y, Wang Y, Lu W, Guo M.

Current application of MOFs based

heterogeneous catalysts in catalyzing

10.1002/bbb.2486

[31]. Liao W, Zhang X, Ke S, Shao J, Yang H,

Zhang S, Chen H. The influence of

biomass

temperature

species

on

and

pyrolysis

transesterification/esterification

for

carbon-retention

298

G. Saragih., et al.

Chempublish Journal, 9(2) 2025, 287-299

ability and heavy metal adsorption

property during biochar aging. Fuel

Processing

1;240:107580.

10.1016/j.fuproc.2022.107580

[32]. El-Sayed SA, Mostafa ME. Kinetics,

thermodynamics, and combustion

characteristics of Poinciana pods using

Technology.

2023

Feb

DOI:

TG/DTG/DTA

Conversion

techniques.

and Biorefinery. 2023

Biomass

Aug;13(13):11583-607.

DOI:

10.1007/s13399-021-02021-8

299