Available online at website: https://journal.
id/index.
php/bcrec Bulletin of Chemical Reaction Engineering & Catalysis, 21 .
2026, 149-167 Original Research Article NaHCOCE-Assisted Synthesis of Ni-Promoted Sulfated Mesoporous Silica for the Hydrocracking of Used Cooking Oil into Biogasoline Karna Wijaya1*.
Marini Fairuz Vebryana1.
Niko Prasetyo1.
Aldino Javier Saviola1.
Wahyu Dita Saputri2.
Amalia Kurnia Amin3.
Latifah Hauli4.
Saharman Gea5 1Department of Chemistry.
Faculty of Mathematics and Natural Sciences.
Universitas Gadjah Mada.
Yogyakarta 55281.
Indonesia.
2Research Center for Hydrodynamics Technology.
National Research and Innovation Agency (BRIN).
The B.
Habibie Science and Technology Area.
South Tangerang.
Banten 15314.
Indonesia.
3Research Center for Catalysis.
National Research and Innovation Agency (BRIN).
The B.
Habibie Science and Technology Area.
South Tangerang.
Banten 15314.
Indonesia.
4Research Center for Molecular Chemistry.
National Research and Innovation Agency (BRIN).
The B.
Habibie Science and Technology Area.
South Tangerang.
Banten 15314.
Indonesia.
5Department of Chemistry.
Faculty of Mathematics and Natural Sciences.
Universitas Sumatera Utara.
Medan 20155.
Indonesia.
Received: 9thNovember 2025.
Revised: 25th December 2025.
Accepted: 26th December 2025 Available online: 28th December 2025.
Published regularly: April 2026 Abstract Biofuel production from biomass sources remains a key area of research, aimed at reducing reliance on fossil fuels and promoting environmental sustainability.
This study investigates the conversion of used cooking oil (UCO) into biogasoline via catalytic hydrocracking, employing sulfated mesoporous silica dispersed with nickel as the catalyst.
Mesoporous silica was synthesized using tetraethyl orthosilicate (TEOS) and NaHCOCE as the template, followed by a hydrothermal method to introduce sulfate groups and nickel metal.
Among the synthesized catalysts.
SMS-2 exhibited the highest acidity across varying sulfuric acid concentrations, while 1 Ni/SMS-2 demonstrated superior acidity compared to other nickel loadings.
The SiOCC.
SMS-2, and 1 Ni/SMS-2 catalysts were evaluated for UCO hydrocracking in a semi-batch double-furnace reactor operated at an optimum temperature of 550 AC for 2 h, with a hydrogen flow rate of 20 mL.
minAA under atmospheric pressure.
Modifying mesoporous silica with sulfuric acid and nickel significantly enhanced its catalytic performance, with the 1 Ni/SMS-2 catalyst achieving the highest liquid product yield .
and gasoline fraction .
47%) at an optimum catalyst-to-feed ratio of 1:100 .
Notably, the resulting biogasoline exhibited a calorific value comparable to commercial gasoline and was free of aromatic hydrocarbons, indicating the potential for cleaner combustion.
This study provides valuable insights into the effectiveness of mesoporous silica-based catalysts, highlighting their acid site modulation capabilities for efficiently transforming waste into high-value fuels.
Copyright A 2026 by Authors.
Published by BCREC Publishing Group.
This is an open access article under the CC BY-SA License .
ttps://creativecommons.
org/licenses/by-sa/4.
Keywords: Biofuel production.
catalytic hydrocracking.
mesoporous silica.
renewable energy How to Cite: Wijaya.
Vebryana.
Prasetyo.
Saviola.
Saputri.
Amin.
Hauli.
Gea.
NaHCOCE-Assisted Synthesis of Ni-Promoted Sulfated Mesoporous Silica for the Hydrocracking of Used Cooking Oil into Biogasoline.
Bulletin of Chemical Reaction Engineering & Catalysis, 21 .
, 149-167.
9767/bcrec.
Permalink/DOI: https://doi.
org/10.
9767/bcrec.
Introduction The residential sectors remain highly energy dependent, with global demand continuing to rise because of population growth, technological * Corresponding Author.
Email: karnawijaya@ugm.
id (K.
Wijay.
advancement, and improved living standards.
2021, global primary energy consumption reached 21 gigatonnes of oil equivalent (Gto.
Continued reliance on fossil fuels as the dominant energy source has raised serious environmental degradation, and long-term energy Excessive fossil fuel use is a major bcrec_20531_2025 Copyright A 2026.
ISSN 1978-2993.
CODEN: BCRECO
Bulletin of Chemical Reaction Engineering & Catalysis, 21 .
, 2026, 150 contributor to climate change, air pollution, and greenhouse gas emissions.
For example, motor vehicles in Pekanbaru City.
Indonesia, emit 50 tons of COCC per day .
, underscoring the severity of transport-related emissions in rapidly urbanizing regions.
These challenges have intensified global efforts to transition toward sustainable and renewable energy systems, particularly in developing environmental protection are closely linked.
Biofuels derived from waste resources have attracted growing interest due to their combined benefits of energy production and waste Used cooking oil (UCO), a readily available waste stream generated by households, restaurants, and the food industry, represents a particularly promising feedstock.
Improper disposal of UCO poses significant environmental risks, including water pollution and sewer blockage, while weak regulatory oversight in regions such as Yogyakarta.
Indonesia, has led to uncontrolled trading and reuse .
Chemically.
UCO is rich in triglycerides dominated by longchain fatty acids, making it well-suited to produce gasoline-range hydrocarbons.
Its valorization into biofuel, therefore, aligns with circular economy principles by improving resource efficiency, reducing waste generation, and minimizing competition with food resources .
Catalytic hydrocracking is recognized as one of the most effective routes for converting vegetable oilAebased feedstocks into gasoline-range operating conditions .
This process enables simultaneous deoxygenation, cracking, and isomerization reactions, resulting in high-quality fuel products.
Catalyst design plays a critical role in determining conversion efficiency, product selectivity, and resistance to deactivation, making the development of robust and highly active catalysts a key challenge in biofuel research.
Silica-based considerable attention for biofuel applications due to their low cost, high surface area, tunable porosity, and excellent thermal stability.
Mesoporous silica materials, with pore diameters between 2 and 50 nm, offer improved mass transfer and accessibility for bulky triglyceride molecules during hydrocracking processes .
Ae.
Various structure-directing agents have been employed to tailor mesoporous silica frameworks, (CTAB) .
, cetyltrimethylammonium chloride (CTAC) .
, polyethylene glycol (PEG-.
, and Pluronic F108 .
In this study, sodium bicarbonate (NaHCOCE) was used as an environmentally benign pore-forming agent to synthesize mesoporous silica, followed by sulfation with sulfuric acid (HCCSOCE) to enhance acidity, pore volume, and pore diameter .
High hydrocracking, as strong Brynsted acid sites promote CAeC bond cleavage and skeletal isomerization .
Accordingly, sulfated catalysts have demonstrated excellent performance in a wide range of acid-catalyzed organic reactions .
Despite their strong acidity, sulfated mesoporous silica catalysts are prone to compromises long-term stability.
Incorporation of transition metals has therefore been widely explored to introduce hydrogenation functionality and suppress coke deposition.
Nickel (N.
, an earth-abundant and cost-effective transition metal, exhibits high catalytic activity in hydrocracking .
, hydroisomerization .
, and hydrogenation reactions .
, making it particularly attractive for biofuel upgrading applications .
Our previous study .
showed that a Ni-impregnated sulfated ZrO2/pillared bentonite catalyst achieved a gasoline yield of 30.
52% from coconut oil at 450 AC.
Similarly.
Riyandi et al.
reported that nickel supported on rice husk ash (Ni/RHA) converted oleic acid into bio-hydrocarbons with a conversion 25% at 285 AC and 40 bar, further demonstrating the effectiveness of Ni-based hydrocracking-based To the best of our knowledge, the hydrothermal synthesis of nickel-impregnated sulfated mesoporous silica catalysts in the presence of NaHCOCE for the conversion of UCO into biogasoline has not yet been reported.
The hydrothermal approach employed in this work provides a controlled aqueous environment under elevated temperature and autogenous pressure, promoting homogeneous nucleation and uniform dispersion of nickel and sulfate species throughout the silica framework.
Under these conditions, precursor species readily penetrate mesoporous channels and interact with surface silanol groups, resulting in well-dispersed active sites and enhanced structural stability.
This strategy favors the incorporation of nickel and sulfate species within the internal pore network rather than on the external surface, thereby improving active-site accessibility and catalytic Moreover, hydrothermal synthesis allows precise control over temperature, pH, and precursor concentration, minimizing particle agglomeration and yielding catalysts with uniform morphology and high phase purity.
Compared with conventional mechanical stirring or wet impregnation methods, this approach is also more energy efficient and environmentally benign .
By comparison.
Nadia et al.
reported that a NiMo-impregnated hierarchical silica catalyst prepared via conventional wet Copyright A 2026.
ISSN 1978-2993 Bulletin of Chemical Reaction Engineering & Catalysis, 21 .
, 2026, 151 impregnation produced only an 18.
64% gasoline fraction from waste frying oil at 475 AC.
Accordingly, this study aims to advance the rational design of silica-based catalysts for sustainable biofuel production and to establish UCO as a viable and renewable feedstock for biogasoline synthesis.
By integrating mesoporous silica architecture, sulfation-induced acidity, and nickel-based hydrogenation functionality through hydrothermal synthesis, this work seeks to develop an efficient and environmentally friendly hydrogen pressure.
Materials and Methods 1 Materials Mesoporous silica was synthesized using tetraethyl orthosilicate (TEOS, 98%.
Merc.
, ethanol .
Merc.
, methanol .
Merc.
, hydrochloric acid (HCl, 37%.
Mallinckrod.
, sodium bicarbonate (NaHCOCE, 99%.
Merc.
, and silver nitrate (AgNOCE, 99%.
Merc.
Sulfation was carried out using sulfuric acid (HCCSOCE, 98%.
Smart La.
, while nickel was introduced from nickel(II) chloride hexahydrate (NiClCCA6HCCO, 99%.
Merc.
All chemicals were of analytical grade and used without further purification.
Hydrogen (HCC) and nitrogen (NCC) gases were supplied by PT Surya Indotim Imex, and deionized water was obtained from OneMed.
Used cooking oil (UCO) collected from households was employed as the feedstock.
Prior to analysis, the UCO was heated at 120 AC to remove residual moisture and subsequently centrifuged at 2000 rpm for 20 min to eliminate suspended impurities.
Its physicochemical properties and fatty acid composition are summarized in Table 1.
Commercial gasoline (Pertalite.
RON .
obtained from PT Pertamina was used as a reference fuel.
The physicochemical properties of the UCO, including acid value, saponification value, and Table 1.
Selected physicochemical properties of the UCO used in this study.
Properties Acid value .
g KOH/g oi.
Saponification value .
g KOH/g FFA content (%) Fatty acid composition (%) Myristic acid Palmitic acid Linoleic acid Oleic acid Stearic acid Total fatty acid Results free fatty acid (FFA) content, were determined using standard titration methods.
The acid value was measured according to ASTM D664 using a standardized KOH solution in ethanol as the titrant and phenolphthalein as the indicator.
The saponification value and FFA content were determined following ASTM D5558 and AOCS Cd 3d-63, respectively.
For saponification value determination, the UCO sample was refluxed with an excess of alcoholic KOH solution, and the KOH back-titrated standardized HCl using phenolphthalein as the The FFA content was determined by titrating the oil sample with standardized KOH The fatty acid composition of the UCO was analyzed using a gas chromatographyAemass spectroscopy (GCAeMS.
Shimadzu QP2010S) equipped with a DB-5MS capillary column .
m y 0.
25 mm y 0.
25 AA.
Prior to analysis, the UCO was esterified using methanol and concentrated HCCSOCE as the catalyst to convert free fatty acids (FFA.
into fatty acid methyl esters (FAME.
following a standard acid-catalyzed esterification Synthesis of Mesoporous Silica Mesoporous silica was synthesized via an acid-catalyzed solAegel method using TEOS as the silica precursor.
In a 250 mL beaker, 8.
4 mL of TEOS was mixed with 0.
795 g of NaHCOCE and 15 mL of ethanol and stirred magnetically at 600 Separately, 15 mL of 2 M HCl was added dropwise at a rate of approximately one drop per second under continuous stirring to initiate TEOS hydrolysis and condensation, resulting in the formation of a white gel after approximately 1 h.
The gel was aged statically at room temperature for 12 h, centrifuged at 2000 rpm for 20 min, and washed repeatedly with deionized water until no turbidity was observed upon addition of AgNOCE solution, confirming complete chloride removal.
The washed gel was dried at 100 AC for 3 h and subsequently refluxed with 50 mL of methanol at 65 AC for 72 h in a 250 mL roundbottom flask under magnetic stirring.
The solid product was then centrifuged, dried again at 100 AC for 3 h, and calcined at 500 AC for 4 h with a heating rate of 10 AC.
minAA in air.
The resulting white powder was sieved through a 270-mesh sieve and denoted as SiOCC.
Sulfation of Mesoporous Silica Sulfation of mesoporous silica was performed following a modified hydrothermal procedure based on Pratika et al.
Briefly, 5 g of SiOCC was mixed with 50 mL of HCCSOCE solution with concentrations of 1.
0, 1.
5, or 2.
0 M and stirred at 600 rpm for 30 min in a Teflon-lined autoclave.
The autoclave was then heated at 100 AC for 4 h.
Copyright A 2026.
ISSN 1978-2993 Bulletin of Chemical Reaction Engineering & Catalysis, 21 .
, 2026, 152 The centrifugation at 2000 rpm for 20 min, dried at 120 AC for 3 h, and calcined at 500 AC for 4 h.
The sulfated samples were designated SMS-1.
SMS1.
5, and SMS-2 according to the HCCSOCE concentration used.
Their acidities were temperatureprogrammed desorption (NHCEAeTPD).
Nickel Impregnation Mesoporous Silica Sulfated Nickel impregnation was performed on the most acidic sulfated mesoporous silica sample (SMS-X).
Three grams of SMS-X was impregnated with 1, 2, or 3 wt% Ni using aqueous solutions of NiClCC.
6HCCO dissolved in 50 mL of deionized water.
The required amount of nickel precursor was calculated using Equation .
The suspension was stirred for 30 min in a Teflon-lined autoclave and subsequently heated at 100 AC for 4 h.
The solvent was then evaporated at 120 AC for 3 h.
The impregnated samples were calcined at 500 AC for 4 h under a nitrogen flow of 20 mL.
minAA and subsequently reduced at 500 AC for 4 h under hydrogen flow .
minAA).
The resulting catalysts were designated as 1 Ni/SMS-X, 2 Ni/SMS-X, and 3 Ni/SMS-X.
Their acidities were further analyzed by NHCEAeTPD.
Mass of the NiCl2 .
6H2 O precursor = molecular mass of NiClCCA6HCCO yCyW 1yatomic mass of Ni .
where C is targeted metal concentration .
t%) and W is mass of SMS-X matrix .
Figure 1.
Schematic diagram of the hydrocracking reactor used in this study.
Hydrogen tank.
Flowmeter.
Thermocouple.
Catalyst .
Feed furnace.
Condenser.
Liquid product container.
Hydrocracking of UCO The optimum hydrocracking temperature was determined through non-catalytic thermal cracking experiments conducted at 500, 550, and 600 AC under a hydrogen flow rate of 20 mL.
minAA for 2 h.
The temperature yielding the highest liquid product fraction .
AC) was selected for subsequent catalytic experiments.
Catalytic hydrocracking was performed at 550 AC under continuous hydrogen flow .
minAA) using SiOCC.
SMS-2, and 1 Ni/SMS-2 as catalysts.
The catalyst-to-feed ratio was fixed at 1:100 .
, corresponding to 0.
1 g of catalyst per 10 g of UCO.
Reactions were conducted in a semi-batch reactor equipped with a double-furnace system under atmospheric pressure for 2 h (Figure .
During operation, the catalyst placed in the upper chamber and the feedstock in the lower chamber were preheated to 200 AC.
The temperature was then increased to 550 AC to vaporize the feed, allowing the vapors to pass through the catalyst bed under hydrogen flow.
Liquid hydrocarbons, non-condensable gases, and coke were produced during the reaction.
Reactor temperature was continuously monitored using a thermocouple positioned in contact with the reactor wall.
The hydrogen flow rate and narrow reactor diameter ensured laminar gas flow, thereby minimizing external mass and heat transfer limitations and allowing the reaction rate to be governed primarily by intrinsic catalytic kinetics.
The semi-batch, isothermal configuration minimized temperature gradients and ensured uniform reaction conditions.
Additional experiments using 1 Ni/SMS-2 were conducted at catalyst-to-feed ratios of 1:100, 2:100, and 3:100 .
Product yields of liquid, gas, and coke were calculated using Equations .
Ae.
The gasoline, diesel, and nonhydrocarbon fractions in the liquid products were quantified by GCAeMS analysis using Equations .
Ae.
, where Ag.
Ad.
An, and Atotal represent the chromatographic peak areas of gasoline, diesel, non-hydrocarbons, and total components.
The liquid product exhibiting the highest gasoline yield was further characterized using Fourier transform infrared spectroscopy (FTIR.
Thermo Scientific Nicolet iS.
and analyzed for calorific value using a Parr 6100 oxygen bomb The spent catalyst obtained after three consecutive reusability cycles was characterized by field-emission scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (FESEMAeEDX) and transmission electron microscopy (TEM).
Liquid product .
t%) = Copyright A 2026.
ISSN 1978-2993 weight of the liquid product .
weight of feed .
Bulletin of Chemical Reaction Engineering & Catalysis, 21 .
, 2026, 153 Coke .
t%) = .
eight of inal catalystOeweight of initial catalys.
g weight of feed .
y 100% .
Gas .
t%) = 100% Oe liquid product Oe coke ycUycUg .
t%) = ycUycUd .
t%) = ycUycUn .
t%) = yayag yayatotal yayad yayatotal yayan yayatotal weight of liquid product .
weight of feed .
weight of liquid product .
weight of feed .
weight of liquid product .
weight of feed .
y 100% .
y 100% .
y 100% .
Results and Discussion Functional Groups Identification of the Catalysts The FTIR spectra of SiOCC.
SMS-1.
SMS-1.
SMS-2, 1 Ni/SMS-2, 2 Ni/SMS-2, and 3 Ni/SMS-2 are presented in Figure 2.
All samples exhibit characteristic absorption bands associated with the silica framework.
The bands observed at approximately 467 cmAA and 802Ae805 cmAA are attributed to the bending and symmetric stretching vibrations of SiAeOAeSi bonds.
In addition, the asymmetric stretching vibration of the SiAeOAeSi network appears in the range of 1088Ae1096 cmAA, which is consistent with previously reported silica-based materials .
The broad absorption band detected at 3451Ae 3458 cmAA corresponds to the stretching vibration of surface hydroxyl groups (SiAeOH), while the band at 1636Ae1640 cmAA is assigned to the bending vibration of molecularly adsorbed water.
These features indicate the presence of surface hydroxyl groups, which are known to play an important role in anchoring sulfate species and metal ions on the silica surface.
The presence of sulfate species is evidenced by absorption bands in the 950Ae1250 cmAA region, attributed to the stretching vibration of SAeOH This region overlaps with the asymmetric stretching vibration of SiAeOAeSi bonds, resulting in broadened and intensified bands.
Such overlap arises from the coordination of sulfate ions with oxygen atoms on the silica surface, which lowers the symmetry of the sulfate complex and shifts its vibrational modes toward lower wavenumbers .
This observation confirms the successful sulfation of the silica support.
Notably, no distinct new absorption bands are observed after nickel impregnation.
This absence may be attributed to the low nickel loading and the homogeneous dispersion of nickel species on the sulfated silica support, which limits the formation of bulk NiO phases detectable by FTIR.
These results suggest that nickel incorporation does not significantly alter the fundamental silica framework or the coordination environment of sulfate species.
Acidity of the Catalysts Catalyst acidity is a crucial factor in determining catalytic activity and selectivity for the hydrocracking process.
Results of the NHCEAe TPD analysis are summarized in Table 2, with Table 2.
Total acidity of the catalysts.
Catalyst
SiO2
SMS-1
SMS-1.
SMS-2
1 Ni/SMS-2 2 Ni/SMS-2 3 Ni/SMS-2 Acidity .
mol/g NH.
Figure 2.
FTIR spectra of SiO2.
SMS-1.
SMS-1.
5, and SMS-2 (A).
1 Ni/SMS-2, 2 Ni/SMS-2, and 3 Ni/SMS2 (B).
Copyright A 2026.
ISSN 1978-2993 Bulletin of Chemical Reaction Engineering & Catalysis, 21 .
, 2026, 154 desorption curves presented in Figure 3.
NHCEAe TPD profiles show that pristine SiOCC exhibits only weak ammonia desorption, confirming the presence of very weak acidic sites associated with surface silanol groups.
Upon sulfation, the total acidity increases markedly, and highertemperature desorption features become more pronounced, indicating the generation of stronger acid sites related to sulfate species anchored on the mesoporous silica framework.
Increasing sulfate concentration from SMS-1 to SMS-2 results in a corresponding increase in acidity, consistent with the formation of sulfate-derived Brynsted acid sites.
SMS-2 exhibits the highest acidity value, followed by its impregnation with nickel metal .
Ni/SMS-2, 2 Ni/SMS-2, and 3 Ni/SMS-.
Table 2 indicates that a 1 wt% nickel concentration yields the highest acidity among the concentrations This finding suggests that nickel metal impregnation enhances catalyst acidity, as nickel provides vacant 4p orbitals that serve as Lewis acid sites, accepting electron pairs from other However, at 2 wt% and 3 wt% nickel loads, acidity decreases due to excessive metal loading, which results in metal agglomeration outside the material's pores.
Both Brynsted and Lewis acid sites contribute to intermediate formation in hydrocracking, so the combination of both acid sites enhances catalyst performance and hydrocracking efficiency.
X-ray Diffractogram Analysis of the Catalysts The XRD patterns of SiOCC.
SMS-1.
SMS-1.
and SMS-2 are presented in Figure 4A, while those of 1 Ni/SMS-2, 2 Ni/SMS-2, and 3 Ni/SMS-2 are shown in Figure 4B.
The broad peak at 2 = 22A indicates the amorphous nature of the synthesized silica, consistent across all samples (JCPDS 39-1.
The retention of the broad peak shape suggests that sulfate addition does not Figure 3.
NH3AeTPD curves of SiO2.
SMS-1.
SMS-1.
5, and SMS-2 (A).
1 Ni/SMS-2, 2 Ni/SMS-2, and 3 Ni/SMS-2 (B).
Figure 4.
X-ray diffractograms of .
SiO2, .
SMS-1, .
SMS-1.
5, and .
SMS-2 (A).
1 Ni/SMS-2, .
2 Ni/SMS-2, and .
3 Ni/SMS-2 (B).
Copyright A 2026.
ISSN 1978-2993 Bulletin of Chemical Reaction Engineering & Catalysis, 21 .
, 2026, 155 affect the catalyst structure.
Distinctive peaks for Ni metal impregnated onto the sulfated mesoporous silica are largely identical, indicating that the impregnation technique does not alter the structure of the sulfated mesoporous silica.
Nickel nanoparticles with face-centered cubic .
structure display notable peaks at 2 = 44.
, 51.
85A .
, and 76.
37A .
(JCPDS 03Ae 1.
, with peak intensity increasing as more metal is impregnated onto the sulfated mesoporous silica.
Based on the XRD data, it can be concluded that the crystallite size of Ni increases with higher Ni loading.
At low Ni loadings, nickel species are more evenly dispersed across the support surface due to stronger metalAe support interactions.
At higher loadings, dispersion becomes less effective, leading to the clustering of metal particles and the formation of larger crystallites.
Textural Properties of the Catalysts The textural properties of all catalysts are summarized in Table 3.
The specific surface area was determined using the BrunauerAeEmmettAe Teller (BET) equation.
Incorporation of NaHCOCE as a pore-forming agent released COCC during calcination, effectively generating silica materials with mesoporous pore diameters.
Upon sulfation and subsequent nickel impregnation, both SMS-2 and 1 Ni/SMS-2 exhibited a notable decrease in specific surface area compared to pristine SiOCC.
This reduction results from partial surface coverage and micropore blockage by sulfate species and nickel particles, as confirmed by the presence of sulfur and nickel in Table 4.
The deposition of these species within or near pore openings limits NCC adsorption, leading to a lower measured surface area .
Despite the observed decrease in BET surface area.
SMS-2 and 1 Ni/SMS-2 exhibit an increase in average pore diameter as determined by BJH pore size distribution analysis.
This apparent contradiction can be explained by structural rearrangements occurring during sulfation and subsequent nickel loading.
Acidic treatment with HCCSOCE can partially etch the silica framework, leading to wall thinning and the merging of adjacent mesopores, which results in an enlargement of the average pore diameter.
Simultaneously, sulfate anchoring and nickel dispersion modify the pore walls and internal surfaces, producing fewer but broader accessible Consequently, the total pore volume slightly increases after sulfation due to pore expansion, impregnation, indicating that nickel species occupy part of the internal voids while preserving the mesoporous structure.
These combined effects explain the simultaneous decrease in specific surface area and increase in average pore Such textural evolution is consistent with previous studies reporting that surface functionalization and metal deposition can induce pore enlargement while reducing the number of accessible adsorption sites, depending on the balance between framework etching and pore Figure 5A shows the NCC adsorptionAe desorption isotherms of SiOCC.
SMS-2, and 1 Ni/SMS-2.
All exhibit type IV isotherms with distinct hysteresis loops, characteristic of condensation occurs in mesopores .
The Table 3.
Textural properties of the catalysts.
Catalyst Specific area .
Total pore
SiO2
SMS-2
1 Ni/SMS-2 Average .
Figure 5.
N2 adsorption-desorption isotherm curves (A).
Pore diameter distribution curves (B) of the Copyright A 2026.
ISSN 1978-2993 Bulletin of Chemical Reaction Engineering & Catalysis, 21 .
, 2026, 156 presence of hysteresis confirms mesoporosity but does not necessarily ensure accessibility to large reactant molecules such as triglycerides, since this also depends on pore connectivity, tortuosity, and surface chemistry.
SiOCC displays an H2-type hysteresis loop, typically associated with disordered pores and nonuniform size distributions caused by pore blocking or necking.
In contrast.
SMS-2 and 1 Ni/SMS-2 exhibit H1-type loops, indicating more uniform cylindrical mesopores with open and interconnected channels .
This transformation suggests that sulfation and nickel impregnation influence the silica framework.
During sulfation, the acidic medium partially hydrolyzes the siloxane network, leading to wall thinning and Subsequent treatment and nickel incorporation promote redeposition of silanol and sulfate species, stabilizing the restructured framework and yielding a more ordered morphology with slightly enlarged channels.
Figure 5B presents the pore size distribution curves obtained from the desorption branch using the BarrettAeJoynerAeHalenda (BJH) method.
IUPAC mesoporous materials due to the metastability of the adsorption branch.
The unimodal, narrow distributions with pore sizes mainly between 2 and 14 nm confirm well-defined mesoporosity.
The sharp peaks centered at 6Ae8 nm for SMS-2 and 1 Ni/SMS-2 reflect uniform pore diameters and reduced textural heterogeneity compared with SiOCC, which shows a broader distribution indicative of less structural regularity.
The evolution from H2- to H1-type hysteresis, together with the narrower pore size distribution, incorporation under hydrothermal conditions not only modify surface chemistry but also reorganize the silica framework, producing a more ordered mesoporous network.
Such textural features are beneficial for catalytic applications, ensuring efficient diffusion pathways and maintaining adequate surface area for active-site exposure.
Thermal Stability Analysis of the Catalysts The thermal stability of SiOCC.
SMS-2, and 1 Ni/SMS-2 was evaluated by TG/DTA, as shown in Figure 6.
The TG curves are expressed as Table 4.
EDX results of the catalysts.
(*nd = not Catalyst
SiO2
SMS-2
1 Ni/SMS-2 Elements .
t%) Figure 6.
TG/DTA profiles of .
SiO2, .
SMS-2, and .
1 Ni/SMS-2.
Copyright A 2026.
ISSN 1978-2993 Bulletin of Chemical Reaction Engineering & Catalysis, 21 .
, 2026, 157 percentage mass loss to ensure valid comparison among samples of different initial weights.
Three major weight-loss regions are identified.
The first region .
Ae110 AC) corresponds to the removal of physically adsorbed water .
SiOCC exhibits the highest loss (OO15.
44%) compared with SMS-2 .
05%) and 1 Ni/SMS-2 .
49%),
indicating greater surface hydrophilicity and moisture adsorption.
This step produces an endothermic peak at 77 AC, consistent with dehydration (Equation .
Endothermic peaks above 400 AC confirm these transformations.
The total weight losses of SiOCC.
SMS-2, and 1 Ni/SMS-2 are 32.
36%, 6.
49%, respectively, indicating that sulfation and nickel loading enhance structural integrity and thermal resistance.
Overall, surface modification stabilizes the silica framework by reducing hydroxyl content and forming thermally robust sulfateAemetal interactions, yielding high-temperature SiOCC.
2HCCO Ie SiOCC 2HCCO Morphological Analysis and Elemental Composition of the Catalysts .
The second region .
Ae355 AC) is attributed to the condensation of vicinal silanol groups into siloxane bonds (SiAeOAeS.
The reduced mass losses of SMS-2 .
43%) and 1 Ni/SMS-2 .
compared with SiOCC .
92%) indicate fewer surface hydroxyls due to sulfation and nickel The third region .
Ae625 AC) corresponds to the removal of geminal silanol groups and the thermal decomposition of surfacebound sulfate species.
Since free HCCSOCE can not exist above 338 AC, the decomposition involves metalAesulfate or SiAeOAeSOCEH species releasing SOCE and OCC, as detailed in Equations .
AeSOCEH.
Ie AeO.
SOCE
SOCE Ie SOCC AOCC Surface Morphological characterization of the catalyst materials was performed using FESEM and TEM.
Figure 7 presents FESEM images of SiOCC and catalysts with significant acidity changes due to sulfate addition (SMS-.
and metal loading .
Ni/SMS-.
The micrographs show that the SiOCC catalyst has a chunk-like morphology with varying sizes, while the addition of sulfate to the support results in an SMS-2 catalyst with an uneven surface and non-uniform particle size, attributed to the agglomeration of SOCEAA ions.
This observation is consistent with previous studies indicating that sulfated silica materials produce non-uniform particles and aggregates due to the presence of sulfate ions .
As shown in Figure 7, nickel impregnation on sulfated mesoporous silica results in a surface morphology with multiple lumps linked to larger Elemental mapping images, provided Figure 7.
FESEM images at 25,000 times magnification of .
SiO2, .
SMS-2, and .
1 Ni/SMS-2.
Copyright A 2026.
ISSN 1978-2993 Bulletin of Chemical Reaction Engineering & Catalysis, 21 .
, 2026, 158 in Figure 8, confirm the presence of sulfur and nickel on the material's surface .
ee Table .
, mesoporous silica through sulfuric acid treatment and nickel metal impregnation.
Figure 9 presents TEM images of SiOCC.
SMS2, and 1 Ni/SMS-2 materials.
All samples consist of aggregated particles rather than isolated individual particles, which limits the direct visualization of mesopores.
As a result, pore channels are challenging to discern clearly in the TEM images due to particle overlap and Nevertheless, the SMS-2 sample exhibits regions with locally enlarged voids .
ighlighted by red circle.
, which qualitatively support the BJH results indicating an increase in average pore diameter after sulfuric acid This enlargement is attributed to framework modification caused by sulfate In the nickel-impregnated sample, darker contrast regions are observed and can be attributed to nickel species deposited on or within the silica framework, confirming the successful incorporation of nickel.
Although TEM does not provide direct evidence of ordered mesoporous channels, the nitrogen adsorptionAedesorption data demonstrate that mesoporosity is retained.
Therefore.
BJH/BET and TEM results are complementary: BJH and BET analyses provide statistically averaged textural information, while TEM offers localized structural insight that may not fully capture mesopore ordering in aggregated Catalytic Assessments Activity Selectivity This hydrocracking of UCO using SiOCC.
SMS-2, and 1 Ni/SMS-2.
It assesses the effects of acidity modifications through sulfate group and nickel metal additions on the catalytic performance of mesoporous silica catalysts.
Before catalytic hydrocracking, thermal hydrocracking .
ithout a catalys.
was conducted at various temperatures to determine the optimum hydrocracking Table 5 presents the product distribution from thermal hydrocracking at 500, 550, and 600 AC, while Table 6 shows the composition of liquid products.
The data indicate that 550 AC is the ideal temperature for hydrocracking in this study, yielding the highest Figure 8.
Elemental mapping micrographs of .
SiO2, .
SMS-2, and .
1 Ni/SMS-2.
Figure 9.
TEM images at 20.
0 nm magnification of .
SiO2, .
SMS-2, and .
1 Ni/SMS-2.
Copyright A 2026.
ISSN 1978-2993 Bulletin of Chemical Reaction Engineering & Catalysis, 21 .
, 2026, 159 percentage of liquid products and gasoline Excessively temperatures lead to increased gas production, indicating a rise in light-fraction hydrocarbons, ultimately reducing the process's efficiency in generating liquid product.
Table 7 summarizes the product conversion percentages from catalytic hydrocracking.
The variation in liquid product yield clearly demonstrates the significant influence of catalyst composition on reaction performance.
The SiOCC catalyst, with its inherently low surface acidity, produces the lowest liquid yield, reflecting its limited catalytic activity, which refers to the ability of a catalyst to facilitate bond cleavage, hydrogenation, and isomerization reactions that convert triglycerides into smaller hydrocarbon The catalytic activity of mesoporous silica is strongly governed by the nature, strength, and distribution of its acidic sites.
Pristine mesoporous SiOCC possesses only very weak Brynsted acidity originating from surface silanol (SiAeOH) groups, which contributes minimally to hydrocracking Sulfation significantly enhances catalytic performance by introducing sulfate-derived acidic sites that provide sufficient protonic strength to promote CAeC bond cleavage reactions.
With increasing sulfate loading, the density of effective acid sites increases, facilitating more efficient hydrocracking and explaining the improved catalytic activity observed for SMS-1.
SMS-1.
and SMS-2 compared with pristine SiOCC.
Beyond acidity, the mesoporous architecture of the silica support plays a critical role in determining catalytic efficiency.
The high surface area and interconnected mesopore network .
Ae50 n.
enable efficient diffusion of bulky triglyceride Table 5.
Product conversion of the thermal hydrocracking processes.
Temperature (AC) molecules to the active sites and promote rapid desorption of lighter hydrocarbon products.
This mass-transfer limitations and suppresses secondary reactions, such as coke formation.
Moreover, the inherent thermal and mechanical stability of the silica framework preserves pore accessibility and active-site conditions, allowing the enhanced acidity introduced by sulfation to be effectively utilized during the reaction.
Among the sulfated catalysts.
SMS-2 exhibits Subsequent impregnation further modifies the acidic properties of the catalyst.
As summarized in Table 2, the catalyst containing 1 wt% Ni .
Ni/SMS-.
shows the highest acidity among the nickel-loaded This enhancement is attributed to the introduction of Lewis acid sites associated with nickel species, which can accept electron pairs through vacant orbitals and thereby complement the existing Brynsted acid sites .
However, increasing the nickel loading to 2 wt% and 3 wt% leads to a decrease in acidity, likely due to excessive metal deposition and agglomeration that partially blocks the pores and reduces the accessibility of acidic sites.
Both Brynsted and Lewis acid sites play essential roles in hydrocracking by facilitating the formation of reaction intermediates and promoting CAeC bond scission.
Therefore, the balanced coexistence of sulfate-derived Brynsted acid sites and nickel-induced Lewis acid sites in 1 Ni/SMS-2 enhanced catalytic performance and improved hydrocracking As illustrated in Figure 10, the conversion of UCO begins with the hydrogenolysis of Table 7.
Product conversion of the catalytic hydrocracking processes.
Catalyst Product conversion .
t%) Liquid
Gas
SiO2
SMS-2
1 Ni/SMS-2 .
1 Ni/SMS-2 .
1 Ni/SMS-2 .
Product conversion .
t%) Liquid Gas Coke Table 6.
Liquid product yield of the thermal hydrocracking processes toward several hydrocarbon (*determined by GC area of C5AeC.
Hydrocarbon yield .
t%) Temperature (AC) Gasoline selectivity (%)* Gasoline Diesel Total Non-hydrocarbon yield .
t%) Ketone or Fatty Alcohol Total Copyright A 2026.
ISSN 1978-2993 Bulletin of Chemical Reaction Engineering & Catalysis, 21 .
, 2026, 160 triglycerides into FFAs and glycerol-derived The fatty acids subsequently undergo oxygen-removal reactions, including hydrodeoxygenation, hydrodecarbonylation, and hydrodecarboxylation, which involve the cleavage of CAeO bonds and lead to the formation of longchain hydrocarbons.
These deoxygenation pathways are accompanied by the evolution of gaseous products such as HCCO.
CO, and COCC, as schematically indicated in the reaction pathway.
The resulting long-chain hydrocarbons are then converted into gasoline-range hydrocarbons through CAeC bond cracking reactions.
Sulfatederived Brynsted acid sites facilitate protonation carbonium-ion intermediates, while nickel-associated Lewis acid sites promote the formation of carbenium-ion species, thereby enabling effective CAeC bond scission .
The synergistic interaction between Brynsted and Lewis acid sites thus enhances hydrocracking efficiency and gasoline-range product formation.
Although gas-phase products are depicted schematically in Figure 10 to illustrate plausible reaction pathways, quantitative analysis of the gas composition was not conducted in this study.
Therefore, hydrodecarbonylation, hydrodecarboxylation, and cracking pathways cannot be distinguished Nevertheless, the observed liquid product distribution and reduced coke formation on the 1 Ni/SMS-2 catalyst suggest that oxygenremoval and cracking reactions proceed efficiently under the applied conditions.
Future work will focus on detailed gas-phase analysis to further elucidate the dominant reaction pathways.
Thermal hydrocracking results in the lowest liquid product yield, indicating that adding a catalyst significantly enhances the hydrocracking process, as evidenced by the higher liquid product Notably, thermal hydrocracking produces the highest amount of gas products, suggesting that high temperatures in the absence of a catalyst promote irregular chain-breaking reactions through radical mechanisms .
The addition of a catalyst enables these hightemperature reactions to proceed more selectively by providing alternative reaction pathways with lower activation energies, allowing a greater proportion of gas-phase hydrocarbons to be converted into liquid products.
Our investigation into the catalyst-to-feed ratio reveals its critical role in hydrocracking.
The 1 Ni/SMS-2 catalyst, when used at a 1:100 ratio, demonstrates superior liquid product conversion compared to the 2:100 and 3:100 ratios.
This finding emphasizes the importance of carefully controlling catalyst quantities, as excessive catalyst amounts can lead to bulkier particles, reducing the surface area available for reactantcatalyst interaction and thereby diminishing hydrocracking efficiency .
As shown in Table 7, too much of the catalyst causes more coke to be This can be caused by the stronger feed sequestration on the catalyst surface, which makes the reaction products challenging to Later, with the influence of high temperature, carbon deposits will form.
Table 8 presents the yield of each hydrocarbon fraction, including gasoline (CCIAeCCACC), diesel (> CCACC), and non-hydrocarbon .
xygenated compounds such as fatty acids, ketones or aldehydes, and alcohol.
Catalysts with progressively higher acidity enhance selectivity for the gasoline fraction.
As shown in Table 8, the Figure 10.
Plausible reaction scheme for the conversion of UCO into biogasoline catalyzed by the 1 Ni/SMS-2 catalyst.
Copyright A 2026.
ISSN 1978-2993 Bulletin of Chemical Reaction Engineering & Catalysis, 21 .
, 2026, 161 1 Ni/SMS-2 catalyst at a catalyst-to-feed ratio of 1:100 exhibits the highest gasoline yield at 47%, followed by diesel at 19.
96% and nonhydrocarbons at 10.
This is attributed to the presence of sulfate ions and nickel metal, which increase the catalyst's acidity and facilitate the formation of more carbenium and carbonium ions, thereby optimizing the hydrocracking process.
However, as the catalyst quantity increases, the gasoline yield of the 1 Ni/SMS-2 catalyst An excessive amount of catalyst reduces hydrocracking efficiency by yielding more diesel and non-hydrocarbon fractions.
used in the hydrocracking process, limiting optimal hydrogenation and aromatization, which leads to a predominance of olefin compounds in the biogasoline .
Additionally, the abundance of olefins in our hydrocracking products may result from a penta-coordinated carbonium ion hydrogenation to form paraffins.
This outcome is an advantage of this research, as our biogasoline, lacking aromatics, can provide cleaner combustion than commercial gasoline, which has a high aromatic content.
The legislative body limits the amount of aromatics allowed in This is primarily because high levels of aromatics in fuel lead to increased emissions of unburned hydrocarbons, such as carbon monoxide and aromatic compounds like benzene, into the atmosphere .
However, the octane number produced from olefin combustion is relatively low compared to aromatics, indicating the need for further studies to improve biogasoline quality.
The calorific value test, conducted using a bomb calorimeter, is essential to measure the energy content of fuels, specifically their heat release during combustion, which is critical for determining fuel quality and performance.
Table 9 compares the test results of our biogasoline with commercial gasoline.
Biogasoline has a calorific value higher than commercial gasoline, although Liquid Product Evaluation Figure 11 illustrates the hydrocarbon range within the gasoline fraction in the liquid products from hydrocracking compared to commercial Neither hydrocracking products nor commercial gasoline contains hydrocarbon chains with five or six carbon atoms.
Our biogasoline and commercial gasoline present hydrocarbons ranging from CCN to CCACC.
Hydrocarbons with eleven carbon atoms dominate our biogasoline, whereas commercial gasoline primarily consists of ninecarbon hydrocarbons.
Olefins are the primary compounds in our biogasoline, while commercial gasoline mainly contains aromatics.
This discrepancy is due to the atmospheric pressure Figure 11.
Hydrocarbon chain range and .
hydrocarbon composition comparison between liquid product from hydrocracking of UCO using the 1 Ni/SMS-2 catalyst and commercial gasoline.
Table 8.
Liquid product yield of the catalytic hydrocracking processes toward several hydrocarbon (*determined by GC area of C5AeC.
Catalyst
SiO2
SMS-2
1 Ni/SMS-2 .
1 Ni/SMS-2 .
1 Ni/SMS-2 .
Hydrocarbon yield .
t%) Non-hydrocarbon yield .
t%) Gasoline (%)* Gasoline Diesel Total Alcohol Copyright A 2026.
ISSN 1978-2993 Ketone or Carboxylic Total Bulletin of Chemical Reaction Engineering & Catalysis, 21 .
, 2026, 162 the difference is not substantial.
Thus, our biogasoline is comparable to commercial gasoline in terms of energy content.
A fuel's calorific value is an essential measure of its effectiveness for energy production.
Generally, fuels with higher calorific values are considered better because they release more energy per unit of weight or volume when burned .
When the products cool to the initial sample temperature, a higher calorific value indicates that all of the heat generated from fuel combustion is being detected .
This means less fuel is needed to produce the same amount of energy, making it more efficient and cost-effective.
The significance of the calorific value obtained can not be overstated.
In future studies, evaluating additional fuel specifications such as flash point, boiling point, density, kinematic viscosity, octane number, and oxidation stability will be necessary.
This will help enhance confidence in the potential application of this biogasoline in real vehicle FTIR analysis was also performed to compare functional groups between the feed and hydrocracking products.
The FTIR spectra in Figure 12 show a reduction in the peak around 1700 cmAA, indicating a decrease in C=O groups.
This confirms that the biogasoline contain fewer oxygenated compounds.
The reduction in oxygen content is also evident from significant changes in absorption peaks around 1000Ae1250 cmAA, representing CAeO groups .
The results can be explained by how triglyceride and fatty acid molecules undergo carbonAeoxygen bond-breaking before the CAeC bond-breaking stage.
Reusability of the 1 Ni/SMS-2 Catalyst The 1 Ni/SMS-2 catalyst, which demonstrated the highest liquid product conversion and gasoline yield at a catalyst-to-feed ratio of 1:100, was evaluated for reusability over three cycles.
Table 10 presents the results of the product conversion tests for the reused 1 Ni/SMS-2 catalyst.
The decrease in liquid product conversion was accompanied by a reduction in the gasoline yield, as illustrated in Table 11.
These findings suggest that the catalyst's performance deteriorates with increased usage.
The decrease in catalyst performance can be attributed to factors such as sintering and deactivation due to coke production.
The results from FESEMAeEDX Mapping and TEM characterization support this observation.
Figure 13 displays the FESEMAeEDX Mapping and TEM morphological images of the spent Ni 1/SMS-2 catalyst.
After three uses, the morphology of the spent Ni 1/SMS-2 catalyst indicates sintering phenomena, which is evidenced by the aggregation of materials.
Following the reusability tests, the catalyst also experienced deactivation due to coke deposition, as shown by the presence of carbon in Table 12.
Coke blockage of catalyst active sites is common when heterogeneous catalysts are used for biofuel production.
According to Zhou et al.
, coke can be regenerated through at least three methods: hydrogenation, oxidation, and Each technique offers its advantages for coke removal.
However, from a sustainability perspective, the gasification method using CO2 as a mild oxidizing agent is an up-and-coming option Through the Reverse Boudouard (RB) reaction, the coke on the catalyst surface reacts with CO2, which helps improve carbon balance .
The findings of this work provide significant opportunities for other researchers to explore this method further to reduce catalyst deactivation.
Table 12.
Elemental composition of the spent Ni 1/SMS-2 catalyst obtained by EDX.
(*nd = not Figure 12.
FTIR spectra of .
UCO feed and .
liquid product from hydrocracking of UCO using Table 9.
Calorific value test results.
Sample Biogasoline Commercial gasoline Calorific value (MJ/k.
Elements .
t %) Table 10.
Product conversion results from reusability test of the 1 Ni/SMS-2 catalyst.
Usage 1 .
Copyright A 2026.
ISSN 1978-2993 Product conversion .
t%) Liquid Gas Coke Bulletin of Chemical Reaction Engineering & Catalysis, 21 .
, 2026, 163 Comparison Results Between the Present Work with Some Previous Studies Table 13 provides information about previous research on biogasoline production.
Our research findings indicate that nickel metal, as an active metal on sulfated mesoporous silica support, achieves superior results in producing biogasoline from catalytic hydrocracking of UCO compared to chromium metal .
Moreover, this study demonstrates improvement over the work of Rambabu hydroprocessing of date palm seed oil over a tantalum phosphate catalyst at 10 bar HCC Furthermore, our findings compare favorably to those of Ibrahim et al.
, who used a highpressure reactor to convert waste palm oil to Conducting the hydrocracking process at atmospheric pressure is an advantage of our research, as it reduces energy consumption and aligns with the Sustainable Development Goals.
Additionally, our study used only Ni metal, which is cheaper and more abundant in Indonesia.
Therefore, this catalyst could be a promising candidate for green industrial biofuel production in the future.
In another report.
Hasanudin and co-workers .
researched the hydrocracking of crude palm oil with bentonite-ZrN catalyst, producing 21.
Another study by Widyastuti et al.
reported using crude palm oil as feedstock for biogasoline production.
Additionally, research by Aulia and co-workers .
indicated using fresh palm oil as a feedstock.
Since crude palm oil can still be used as raw material for derivative products for human consumption, selecting UCO as feedstock is better to support sustainability and environmental balance.
Consequently, further optimization of hydrocracking parameters is essential to achieve higher liquid product conversion and gasoline yield, along with studies on catalyst reproducibility.
Additional analysis, life-cycle techno-economic assessments, is required to evaluate the biogasoline production method against existing fossil-based gasoline production methods.
Figure 13.
FESEM, .
TEM, and .
elemental mapping images of the spent Ni 1/SMS-2 catalyst.
Table 11.
Liquid product yield from reusability test of the 1 Ni/SMS-2 catalyst.
(*determined by GC area of C5AeC.
Usage 1 .
Gasoline (%)* Hydrocarbon yield .
t%) Gasoline Diesel Total Non-hydrocarbon yield .
t%) Ketone or Carboxylic Alcohol Copyright A 2026.
ISSN 1978-2993 Total Bulletin of Chemical Reaction Engineering & Catalysis, 21 .
, 2026, 164 Conclusion Acknowledgment In summary, mesoporous silica was bicarbonate as a pore-directing agent, followed by treatment with 2 M HCCSOCE and 1 wt% nickel metal impregnation via the hydrothermal method.
This produced the 1 Ni/SMS-2 catalyst, which demonstrated the highest acidity compared to variations in sulfuric acid concentration and nickel loading.
The enhanced acidity of the 1 Ni/SMS-2 catalyst resulted in superior activity and selectivity, achieving a liquid product conversion of 66.
10% and a gasoline fraction of 47% relative to SMS-2 and SiOCC.
Sulfuric acid modification and nickel addition effectively improved the catalytic performance of mesoporous silica for biogasoline production.
Nonetheless, further research is warranted to maximize liquid product conversion and gasoline yield by optimizing the hydrocracking parameters, such as reaction time and hydrogen supply, for its practical scalability.
In addition, fractional distillation must be considered in the next work to separate the non-gasoline fraction.
Thus, the properties can be more matched with commercial The obtained biogasoline, with a calorific value of 42.
63 MJ/kg, closely matches that of .
MJ/k.
technological progress and the demand for biogasoline production from UCO offers promising potential, supporting circular economy initiatives and strengthening energy security.
Collectively, this study presents a safer approach to biogasoline production via catalytic hydrocracking at atmospheric pressure, yielding hydrocarbon products devoid of aromatics, which contributes to cleaner combustion and reduced carbon footprint for a more sustainable future.
The authors would like to express their gratitude to the National Research and Innovation Agency (BRIN) Indonesia and Indonesia Endowment Fund for Education Agency (LPDP) for funding this work through Riset dan Inovasi untuk Indonesia Maju (RIIM) Batch i 2023 Project with Contract Number 30/IV/KS/05/2023 and 2243/UN1/DITLIT/DitLit/PT.
03/2023 .
econd year project based on B1241/II.
5/FR.
03/2/2.
The authors also acknowledge the facilities and scientific support from the Physical Chemistry Laboratory.
Department of Chemistry.
Universitas Gadjah Mada.
Advanced Characterization Laboratories Serpong and the Advanced Physics Imaging Laboratories Serpong, the National Research and Innovation Agency (BRIN) Indonesia through E-Layanan Sains.
CRedit Author Statement Author Contributions:
Wijaya:
Conceptualization.
Formal analysis.
Funding acquisition.
Project administration.
Resources.
Supervision.
Validation.
Writing Ae original draft.
Vebryana: Data curation.
Investigation.
Software.
Visualization.
Writing Ae original draft.
Prasetyo: Formal analysis.
Supervision.
Validation.
Writing Ae review & editing.
Saviola:
Conceptualization.
Methodology.
Visualization.
Writing Ae review & editing.
Saputri:
Formal Supervision.
Validation.
Writing Ae review & editing.
Amin: Formal analysis.
Supervision.
Validation.
Writing Ae review & editing.
Hauli: Formal analysis.
Supervision.
Validation.
Writing Ae review & editing.
Gea: Formal analysis.
Supervision.
Validation.
Writing Ae review & All authors have read and agreed to the published version of the manuscript.
Table 13.
Comparison between the present work with other studies on biogasoline production.
Feedstock Catalyst Operational conditions Coconut oil Ni-BZS 0.
Waste frying oil
Ni2Mo2/HS3 Used cooking oil
Cr-SS 1
Date palm seed oil
TaPa
Waste cooking oil
CoAl2O4
Crude palm oil
Bentonite-ZrN
Crude palm oil
HZSM-5
Palm oil
Z/CNC-4
Used cooking oil 1 Ni/SMS-2 T = 450 AC, t = 1 h.
P = 1 atm, reactor type = T = 475 AC, t = 2 h.
P = atm, reactor type = fixed-bed reactor T = 450 AC, t = 2 h.
P = 1 atm, reactor type = semi-batch reactor T = 400 AC, t = 3 h.
P = 9.
87 atm, reactor type = batch reactor T = 400 AC, t = 1 h.
P = 70 bar, reactor type = continuous high-pressure reactor T = 450 AC, t = 0.
12 h.
P = 1 atm, reactor type = semi-batch reactor T = 400 AC, t = 4 h.
P = not stated, reactor type = not stated T = 550 AC, t = 4 h.
P 1 atm, reactor type = fixed-bed reactor T = 550 AC, t = 2 h.
P = 1 atm, reactor type = semi-batch reactor Copyright A 2026.
ISSN 1978-2993 Obtained biogasoline (%) Ref.
Present Bulletin of Chemical Reaction Engineering & Catalysis, 21 .
, 2026, 165
References