Jurnal Reaksi (Journal of Science and Technolog.
Jurusan Teknik Kimia Politeknik Negeri Lhokseumawe Vol.
23 No.
Desember 2025 ISSN 1693-248X
APPLICATION OF KAOLIN-ZEOLITE CERAMIC FILTER MEMBRANE IN
RECOVERING WASTE OIL INTO USABLE OIL
Muhammad Zaky1*.
Alfian Putra1.
Cut Aja Rahmahwati1 Chemical Engineering.
Lhokseumawe State Polytechnic.
Jl.
Banda Aceh-Medan Km.
Buketrata.
Mosque Punteut.
Blang Mangat.
Lhokseumawe City.
Aceh 24301.
Indonesia *Email: muhammadzakyzaky753@gmail.
ABSTRACT
Several membrane materials are continuously being developed to produce efficient and environmentally friendly filtration media.
This study examines the application of kaolin-zeolitebased ceramic filter membranes in the process of refining used cooking oil into usable oil.
The main materials used are kaolin, zeolite, and PVA as a binder.
The variations in the kaolin:zeolite composition used are 50%:50%, 60%:40%, 70%:30%, 80%:20%, and 100%:0% with sintering times of 1, 2, and 3 hours at a temperature of 1000AC.
Membrane characterization includes density, porosity, flux, morphology tests using a Scanning Electron Microscope (SEM), as well as the removal of Free Fatty Acids (FFA) in used cooking oil.
The results showed that the composition of 50% kaolin and 50% zeolite with a sintering time of 3 hours produced the best performance with a density of 1.
32 g/cmA, porosity of 56.
00%, flux of 143.
93 L/mA.
hour, and the removal capacity of ALB up to 70.
6%, reducing the ALB content from 4.
56% to 1.
34% according to SNI standards.
SEM analysis showed a macroporous structure .
57Ae3.
02 AA.
that supports filtration, while the adsorptive properties of zeolite play a role in reducing polar compounds.
These results prove that kaolin-zeolite ceramic membranes have the potential as an alternative technology in used cooking oil recovery.
Keywords: Ceramic Membrane.
Kaolin.
Zeolite.
Sintering.
Flux.
Free Fatty Acid.
SEM.
fatty acids.
Kaolin serves as the main component of the ceramic, providing a strong structure, while zeolite has adsorption properties that enable it to bind polar compounds.
The combination of these two materials creates a membrane with optimal performance for the purification process, while utilizing locally sourced, environmentally friendly, and affordable materials (Rahman et al.
The challenge in processing used cooking oil lies in its high contaminant content, such as polar compounds and free fatty acids.
One widely developed solution is the application of ceramic membrane technology based on natural materials such as kaolin and zeolite.
These materials are known for their good mechanical properties, high temperature stability, and superior adsorption capacity, enabling them to filter impurities and improve the quality of used cooking oil.
The use of kaolin-zeolite based INTRODUCTION 1 Background Used cooking oil is a household and industrial waste product largely generated from cooking activities.
Repeated use of cooking oil at high temperatures can damage its chemical structure, producing harmful compounds such as free fatty acids (FFA) and other polar compounds that are carcinogenic (Nuryanti et al.
If not managed properly, used cooking oil disposal can pollute the environment, particularly soil and water (Raharjo & Indarto, 2.
Therefore, efforts to recover used cooking oil into more usable oil are crucial to reduce negative environmental impacts while providing added value.
The used cooking oil recovery process using a kaolin-zeolite-based ceramic filter membrane not only aims to filter physical impurities but also reduces the levels of certain chemical compounds, such as free Jurnal Reaksi (Journal of Science and Technolog.
Jurusan Teknik Kimia Politeknik Negeri Lhokseumawe Vol.
23 No.
Desember 2025 ISSN 1693-248X advantages due to the abundant and inexpensive raw materials (Santoso et al.
This study describes a technique for fabricating macroporous ceramic filters using a polymer template, such as polyurethane foam.
In this process, a ceramic slurry is prepared beforehand and the polymer template is dipped into it.
The template serves as a temporary structure to form the macropores in the ceramic After drying and sintering, the polymer template is burned off, leaving the desired pore structure.
A gypsum mold serves as a molding container during drying and to maintain the final shape of the ceramic membrane (Maspupah et al.
In this study, kaolin and zeolite were used as membranes to recover used cooking oil into quality oil that meets health standards.
3 Experimental Treatment Design 1 Fixed Variables - Sintering temperature: 1000AC - Waste cooking oil volume: 1 L - Membrane thickness: 0.
6 cm .
2 Independent Variables - Kaolin: 50%, 60%, 70%, 80%, 100% - Zeolite: 50%, 40%, 30%, 20%, 0% - Sintering Time: 1, 2, and 3 hours 3 Dependent Variable Density Test Porosity Test Flux Test SEM Test Free Fatty Acid Test 4 Experimental and Testing Procedures 1 Procedure for Making KaolinZeolite-Based Ceramic Membranes Prepare kaolin and zeolite in a specific ratio, for example, 50% kaolin and 50% zeolite.
Weigh these ingredients using an analytical Mix the kaolin and zeolite in a glass beaker and stir until thoroughly combined using a spatula or manual Add a binder, such as silicone or Polyvinyl Alcohol (PVA), to make the paste denser and more Mix until homogeneous.
Pour the mixture into the ceramic membrane mold.
Press the mixture evenly to avoid air bubbles in the After drying, remove the membrane from the mold and clean the surface with distilled water to remove dust and any remaining unused material.
Transfer the dried membrane to a furnace and bake at 1000AC for 1, 2, and 3 hours to activate the pore membrane's durability.
After heating, allow the membrane to cool to room temperature.
RESEARCH METHODS
Research methodology 1 Research Place This research was carried out at the Process Unit Laboratory.
Pilot Plant Laboratory.
Operations Unit laboratory of Lhokseumawe State Polytechnic.
2 Tools and Materials 1 Tools used Equipment used in this research includes analytical scales, beaker glass, griding mill, measuring cup, spatula, pressure pump, measuring pipette, burette, furnace .
, caliper, aluminum foil, hot plate stirrer, stirring rod, membrane mold, ball pipette, sieve.
2 Materials used The ingredients used in this research include Used cooking oil, kaolin, zeolite, polyvinyl alcohol (PVA), sodium (NaOH), phenolphthalein indicator (PP), 96% ethanol, 0.
1 N KOH solution, and distilled water .
Jurnal Reaksi (Journal of Science and Technolog.
Jurusan Teknik Kimia Politeknik Negeri Lhokseumawe Vol.
23 No.
Desember 2025 ISSN 1693-248X Visually inspect the membrane surface to ensure there are no cracks or defects.
Store membrane in a dry, tightly closed place to prevent moisture damage.
Analyze the finished membrane, including density, porosity, and filtration performance.
Ensure the membrane meets the standards for use in removing free fatty acids from used cooking oil.
2 Discussion Research on the manufacture of kaolinzeolite based filter membranes in used cooking oil recovery has been carried out testing including density tests, porosity test results, flux tests.
SEM tests and Free Fatty Acid tests.
1 Density Test 2 Free Fatty Acid/FFA Procedure Take 5 mL of used cooking oil before and after filtration into a Add 96% ethanol .
mL) and 3 drops of phenolphthalein indicator.
Titrate with 0.
1 N KOH solution until the pink color persists for 30 Record the volume of KOH used.
Figure 3.
1 Graph of the Density Test Results on Membranes From the density test data above, the highest density was recorded in the 50:50 composition with 1 hour sintering, while the lowest density was found in the 60:40 composition with 3 hours sintering at 1.
g/cmA.
This decrease in density indicates an increase in the number of cavities or pores in the membrane, which is closely related to the increase in porosity.
From the test results, it can be seen that the density value of the ceramic membrane decreases with increasing sintering time for most samples.
For example, at a 50:50 composition, the density decreases from 1.
37 g/cmA at 1 hour of sintering to 1.
32 g/cmA at 3 hours of sintering.
This indicates that the longer sintering process causes the material to become more porous due to the melting of fine particles that form cavities within the membrane structure.
RESULTS AND DISCUSSION
1 Research Results Table 3.
1 Data from Test Results and Observation Analysis KaolinSintering Zeolit Time Compotion .
50:50 60:40 70:30 80:20 Density .
/cmA) Porosity Flux
(%)
(L/mA.
1,37
26,80
68,87
1,35
48,80
125,36
1,32
56,00
143,93
1,19
35,59
91,47
51,64
132,77
1,11
42,99
110,47
1,26
35,48
91,18
1,32
42,91
110,26
1,23
28,14
72,33
30,77
79,12
39,03
100,29
1,24
55,54
142,73
1,19
34,02
87,40
1,19
46,27
118,86
1,17
31,30
80,45
Jurnal Reaksi (Journal of Science and Technolog.
Jurusan Teknik Kimia Politeknik Negeri Lhokseumawe Vol.
23 No.
Desember 2025 ISSN 1693-248X Porosity Test Picture.
3 Graph of the Porosity Test Results on Membranes From the flux test data above, the results show that flux increases with The 50:50 composition with 3 hours of sintering had the highest flux of 143.
93 L/mA.
h, in line with its highest porosity .
00%).
Meanwhile, the lowest flux occurred with the 50:50 composition with 1 hour of sintering, at 68.
87 L/mA.
This significant increase in flux indicates that membranes with high porosity allow for higher fluid flow rates.
However, excessive porosity can also risk reducing the membrane's mechanical Therefore, a balance between flux, porosity, and physical strength is an important consideration in selecting the optimal composition and sintering time.
The flux test describes the membrane's ability to flow water per unit area and Based on the results of a simulation calculation with a filtrate volume of 1 liter, a time of 4 hours, and an effective area of 0.
00363 mA, an initial flux of 68.
L/mA.
h was obtained for a porosity of Next, the flux was calculated in proportion to each porosity value.
Figure 3.
2 Graph of the Porosity Test Results on Membranes From the porosity test data above, the 80:20 composition, sintered for 3 hours, showed the highest porosity at 55.
followed by the 50:50 composition, sintered for 3 hours, at 56.
This indicates that a combination of kaolin and zeolite with a balanced ratio, or a slight kaolin predominance, can produce a highly porous structure when sintered for longer periods.
However, not all increases in sintering time resulted in the highest porosity.
compositions fluctuated, such as the 70:30 composition, which actually decreased in the third sintering cycle .
14%).
This could be due to shrinkage of the material's microstructure due to over-sintering, which causes the pores to begin to close Porosity is an important parameter in determining the membrane's ability to transmit fluids.
Data shows that porosity tends to increase with increasing sintering At a 50:50 composition, porosity increased from 26.
80% to 56.
00% as sintering time increased from 1 to 3 hours.
4 Free Fatty Acid Test Table 3.
2 ALB% Analysis Results Data and ALB% Allowance Flux Test Komposisi ALB Awal (%) ALB Sesudah (%) Penyisihan ALB (%) 50:50% 60:40% 70:30% 80:20% 100:0% 4,56 4,56 4,56 4,56 4,56 1,34 1,41 1,56 1,72 1,88 Based on Table 4.
2, the Free Fatty Acid (FFA) content of used cooking oil before the filtration process was recorded at 4.
which exceeds the quality threshold for edible cooking oil according to the Indonesian National Standard (SNI) .
3Ae 5%).
This indicates that the used cooking oil Jurnal Reaksi (Journal of Science and Technolog.
Jurusan Teknik Kimia Politeknik Negeri Lhokseumawe Vol.
23 No.
Desember 2025 ISSN 1693-248X was no longer suitable for consumption in its original state.
After undergoing filtration with a kaolinzeolite-based ceramic membrane, the FFA content was successfully reduced to 1.
34Ae 88%, with a removal percentage of 58.
8 The 50:50 composition variation yielded the best results with a removal rate of 6%, followed by 60:40 at 69.
1%, 70:30 at 8%, 80:20 at 62.
3%, and 100:0 at 58.
This pattern indicates that the higher the zeolite content in the membrane, the better the FFA removal capacity.
Zeolite acts as an adsorbent due to its surface area and pores that can capture free fatty acid molecules.
50:50 composition demonstrates optimal performance due to the balance between the mechanical properties of kaolin .
s a binder/ceramic forme.
and the adsorptive properties of zeolite.
These results align with research by Rahmawati et al.
, which found that the combination of kaolin and zeolite was effective in reducing FFA levels through filtration and adsorption mechanisms.
Therefore, it can be concluded that varying the kaolin-zeolite composition significantly influences the membrane's effectiveness in removing FFA from used cooking oil.
porosity of 56.
00% and supported high filtration performance in the refining process of used cooking oil.
The analysis of the effect of sintering time on membrane porosity characteristics showed a significant effect on pore formation.
Sintering time of 3 hours gave the best results with a flux of 143.
L/mA.
hour and was able to remove free fatty acids (FFA) up to 70.
reducing the FFA content from 56% to 1.
34%, according to the SNI standard for cooking oil (<2.
5%).
2 Suggestions Based on the conclusions drawn, the following suggestions are given:
Future researchers hope to be able to Conduct additional parameter testing for further research, it is recommended to add testing on other parameters such as compressive strength, resistance to high
BIBLIOGRAPHY