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Abstrak :
Metil laurat merupakan bahan baku atau bahan dasar bagi banyak industri, termasuk industri surfaktan, yang dapat diisolasi dari minyak kelapa. Pada penelitian ini minyak kelapa (VCO) awalnya nitransesterifikasi dengan metanol untuk menghasilkan metil ester dengan menggunakan NaOH sebagai katalis. Metil laurat dipisahkan dari metil ester dengan menggunakan metode pemisahan berdasarkan perbedaan titik leleh. Penelitian ini bertujuan untuk mengkaji pengaruh beberapa variabel dalam transesterifikasi terhadap konsentrasi metil laurat yang dihasilkan. Variabel-variabel yang diamati yaitu suhu (40 oC, 50 oC, 60 oC, 80 oC), waktu reaksi transesterifikasi (0,5 jam, 1 jam, 1,5 jam, 2 jam, 3 jam), dan persen berat katalis NaOH (0,5 %, 1 %, 1,5 %, 2 %, 3 %). Pada penelitian ini, konsentrasi metil laurat secara umum meningkat seiring kenaikan suhu, waktu, dan persen berat katalis. Kondisi optimum diperoleh pada suhu reaksi 60oC, waktu reaksi 2 jam, dan konsentrasi NaOH 2 % berat. Konversi asam laurat menjadi metil laurat yang diperoleh dari kondisi optimum setelah dilakukan pemisahan berdasarkan titik leleh adalah 55,61 %.

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Methyl laurate is a raw or base material for many industries, including surfactant industries. In this research, coconut oil (VCO) is transesterified with methanol to produce methyl ester, using NaOH as the catalyst. Methyl laurate is then separated by method based on the difference in melting point. This research focuses at determining the effects of some variables in transesterification on the concentration of produced methyl laurate. The variables are temperature (40 oC, 50 oC, 60 oC, 80 oC), time of transesterification reaction (0,5 hour, 1 hour, 1,5 hours, 2 hours, 3 hours), and the percent weight of the catalyst NaOH (0,5 %, 1 %, 1,5 %, 2 %, 3 %). Research showed the concentration of methyl laurate increased, following the increased temperature, time, and percent weight of catalysts. Optimal conditions were acquired at reaction temperature of 60oC, reaction time of 2 hours, and percent weight of the catalyst NaOH of 2 %. Laurate acid conversion to methyl laurate that yielded from optimal conditions, after the separation based on melting point, was 55,61 %.

Abstrak :
Pada penelitian ini dilakukan studi pemanfaatan gliseril di-asetil monorisinoleat sebagai aditif penurun titik awan biodiesel. Pembuatan gliseril di-asetil monorisinoleat dilakukan dengan memodifikasi minyak castor yang asam lemaknya berupa asam risinoleat dengan gliserol untuk memperpendek rantai karbon dan asetat sebagai pemodifikasi rantai bercabang. Penelitian dilakukan dalam dua tahap, tahap pertama yaitu pembuatan aditif yang dibagi menjadi dua proses yaitu transesterifikasi minyak castor dengan gliserol menghasilkan gliseril monorisinoleat dan asetilasi gliseril monorisinoleat menghasilkan gliseril di-asetil monorisinoleat. Proses transesterifikasi dilakukan pada suhu 80°C selama 3 jam, dengan variasi rasio komposisi reaktan minyak:gliserol pada 1:1, 1:2, 1:3 dan 1:4. Pemakaian katalis NaOH adalah 0,1 berat serta isopropanol sejumlah 2:1 v/b minyak castor yang direaksikan. Proses asetilasi dilakukan pada suhu 140°C selama 1 jam dengan rasio komposisi reaktan gliseril monorisinoleat : asam asetat anhidrat 1:2. Produk aditif penurun titik awan merupakan gliserol asetil risinoleat 1:2 mengandung 93 gliseril di-asetil monorisinoleat dengan karakteristik titik awan -27°C, titik tuang -27°C, densitas 0,9261 g/cm3, dan viskositas 19,23 cSt. Tahap kedua adalah pencampuran aditif penurun titik awan biodiesel yaitu gliseril di-asetil monorisinoleat dengan biodiesel sawit. Hasil penelitian menunjukkan bahwa gliseril di-asetil monorisinoleat dapat digunakan sebagai aditif penurun titik awan biodiesel dengan viskositas, densitas dan sisa karbon CCR biodiesel tetap memenuhi SNI 7182:2015 sampai dengan penambahan 20 berat aditif ke dalam biodiesel sawit dapat menurunkan titik awan sebesar 2,3°C dan menurunkan titik tuang sebesar 3°C. Sedangkan aditif penurun titik awan komersil dapat menurunkan titik awan sebesar 2°C hanya dengan penambahan 5 berat aditif ke dalam biodiesel, akan tetapi karakteristik viskositas tidak memenuhi SNI 7182:2015. ......A research on the utilization of glyceril di acetyl monoricinoleat as cloud point depressant additivefor biodiesel has been carried out. Glyceril di acetyl monoricinoleat was prepared by modifying castor oil using glycerol, which function was to shorten the length of carbon chains and acetate, which function was to modify the branched chains. This research was conducted in two stages, the first stage was the lab scale production of cloud point depressant additive that consisted of two main processes namely, trans esterification of castor oil with glycerol to produce glyceril mono ricinoleic and acetylation of glyceril mono ricinoleic to produce glyceryl di acetyl monoricinoleic. Trans esterification was performed at 80 C for 3 hours, with a variation in the reactant composition at 1 1, 1 2, 1 3 and 1 4 on the ratio of castor oil glycerol. A mixture of sodium hydroxide 0.1 and isopropanol at 2 1 v b of castor oil reacted, was used as catalyst for this reaction. Furthermore, acetylation was performed at 140°C for 1 hour, using acetic acid as the reactant with composition ratio of glyceryl mono ricinoleate anhydrous acetic acid at 1 2. Cloud point depressant additive that was produced was glyceryl acetyl ricinoleic 1 2 which was formed of 93 glyceryl di acetyl mono ricinoleic having characteristics of cloud point at 27°C, pour point at 27°C, density at 0,9261 gr cm3, and viscosity at 19,23 cSt. The second stage of this research was the blending trials by mixing this additive with B20 and B100 biodiesel. The results showed that glyceryl acetyl ricinoleic can be used as a biodiesel cloud point depressant additive with the viscosity, density and carbon residu CCR of biodiesel meet the requirements of SNI 7182 2015, however it was not working effectively because the cloud point was not decreased significantly. An addition of 20 weight synthetic additive into palm oil biodiesel could only decreases its cloud point by 2,3°C and its pour point by 3°C, while the commercial cloud point depressant additive decrease the cloud point by 2°C with an addition of 5 weight commercial additive into palm biodiesel, however the viscosity characteristic of later mixture did not meet the requirements of SNI 7182 2015.

Abstrak :
ABSTRAK
Minyak kelapa sawit merupakan bahan baku unggul pembuatan biodiesel di Indonesia. Meskipun Indonesia memiliki iklim tropis, Pemanfaatan biodiesel sawit diselidiki memiliki masalah dengan sifat aliran dingin terutama di daerah-daerah dataran tinggi. Masalah umum lainnya dari Biodiesel adalah kemudahan degradasi selama penyimpanan jangka panjang. Minyak kelapa sawit memiliki stabilitas oksidasi yang lebih baik, tetapi titik awannya tinggi karena tingginya kadar asam lemak jenuh. Di sisi lain, minyak mikroalga memiliki titik kabut dan titik tuang yang rendah, tetapi lebih mudah teroksidasi karena tingginya tingkat FAME tak jenuh. Oleh karena itu, kombinasi sifat tak jenuh tunggal dan jenuh antara Minyak Kelapa Sawit dan minyak Mikroalga membuatnya lebih disukai sebagai campuran bahan baku untuk meningkatkan kualitas Biodiesel. Model senyawa alga metil diformulasikan berdasarkan komposisi asam lemak Nannochloropsis sp. dari literatur. Dalam penelitian ini, skema pencampuran minyak dilakukan dengan variasi 5%, 10%, 20%, 30% penambahan Microalgae Oil ke Palm Oil. Transesterifikasi terjadi pada 60-700C dengan penambahan katalis basa 0,6%-wt dan metanol 40% -v/v selama 1-1,5 jam. FAME dianalisis berdasarkan SNI 7182:2015 dengan empat parameter utama diantaranya angka asam total (ASTM D 6644), titik kabut dan titik tuang (ASTM D 2500, dan ASTM D97), dan stabilitas oksidasi (EN 14112). Tujuan dari penelitian ini ialah menentukan rasio campuran yang optimal antara minyak kelapa sawit dan minyak mikroalga untuk produksi biodiesel. Berdasarkan percobaan, rasio campuran biodiesel yang optimal ditemukan pada 5% dengan cloud dan titik tuang masing-masing adalah 15.30C dan 120C. Stabilitas oksidasi dan angka asam 5% yang diperoleh adalah 10,58 jam, dan 0,175 mg KOH /g. Oleh karena itu, campuran biodiesel mengkonfirmasi bahwa asam lemak tak jenuh dari minyak mikroalga dapat meningkatkan sifat aliran dingin dari bahan bakar biodiesel kelapa sawit.

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ABSTRACT
Palm oil is reported as the superior feedstock of biodiesel producing in Indonesia. Although Indonesia has tropical climate, Utilization of palm biodiesel is investigated having problems with the cold flow properties particularly in the high-altitude areas. The other common issue of Biodiesel is the ease of degradation during long-term storage. Palm oil has better oxidation stability, but high cloud point due to the high levels of saturated fatty acids. On the other hand, microalgae oil has low cloud and pour point, but more easily oxidized due to the high levels of unsaturated FAME. Therefore, the combination of monounsaturated and saturated properties between Palm Oil and Microalgae oil makes it preferable as raw materials blending to upgrade the quality of Biodiesel. The model algal methyl compounds were formulated based on fatty acid compositions of Nannochloropsis sp. from the literature. In this research, the oil blending scheme was done by variations 5%,10%,20%,30% of addition Microalgae Oil to Palm Oil. The transesterification occurred at 60-700C with the addition of base catalyst 0.6%- wt and methanol 40%-v/v during 1-1.5 hours. The FAMEs were analysis according to SNI 7182:2015 with four main parameters including total acid number (ASTM D 6644), cloud point and pour point (ASTM D 2500, and ASTM D97 respectively), and oxidation stability (EN 14112). The purpose of this research was to determine the optimum blending ratio between palm oil and microalgae oil for biodiesel production. Based on the experiment, the optimum blending ratio of biodiesel was found on 5% with the cloud and pour point are 15.30C and 120C respectively. The oxidation stability and total acid number of 5% blends obtained were 10.58 hours, and 0.175 mg KOH/g biodiesel respectively. Hence, the biodiesel blends confirm that the unsaturated fatty acids of microalgae oil can enhance the cold flow property of palm biodiesel fuels.

Abstrak :
Biodiesel disintesis melalui reaksi transesterifikasi menggunakan material metal organic frameworks dengan logam Ca (Ca-MOF) sebagai katalis. Ca-MOF disintesis dengan metode hidrotermal pada suhu 110℃. Katalis Ca-MOF dikarakterisasi dengan FTIR, XRD, SEM dan SAA. Variasi pengujian transesterifikasi dilakukan berupa berat katalis (2%, 4% dan 6%), rasio bahan baku dan metanol (1:6, 1:8 dan 1:10) serta jenis bahan baku yang digunakan (minyak kelapa sawit dan lemak ayam). Sampel dengan konversi tertinggi yaitu 8,010% terdapat pada variasi bahan baku minyak kelapa sawit dengan katalis 6% serta rasio minyak dan metanol berjumlah 1:10. Sampel tersebut kemudian diuji dengan empat parameter SNI (densitas, viskositas, bilangan asam dan bilangan iodine) serta dianalisis dengan GC-MS. Hasilnya, sampel memenuhi 3 dari 4 parameter meliputi densitas, viskositas dan bilangan iodine. Sedangkan yield yang didapatkan sebesar 7,457%. Aktivasi katalis kemudian dilakukan pada 300℃, yang kemudian meningkatkan koversi sebesar 12,63%. Rendahnya konversi produk diperkirakan karena rusaknya luas permukaan katalis dikarenakan senyawa turunan N,N-dimetilformida (DMF). ......Biodiesel is synthesized through transesterification reaction using metal-organic frameworks with calcium (Ca-MOF) as the catalyst. Ca-MOF is synthesized via a hydrothermal method at a temperature of 110℃. The Ca-MOF catalyst is characterized using FTIR, XRD, SEM, and SAA. Variations in transesterification testing are conducted by varying the catalyst weight (2%, 4%, and 6%), the feedstock-to-methanol ratio (1:6, 1:8, and 1:10), and the type of feedstock used (palm oil and chicken fat). The sample with the highest conversion, 8.010%, is obtained using palm oil as the feedstock, 6% catalyst, and a feedstockto-methanol ratio of 1:10. This sample is then tested for four SNI parameters (density, viscosity, acid number, and iodine number) and analyzed using GC-MS. The results show that the sample meets 3 out of 4 parameters, including density, viscosity, and iodine number, with a yield of 7.457%. Catalyst activation is then performed at 300℃, resulting in an increased conversion of 12.63%. The low conversion of the product is attributed to the damage to the catalyst surface area caused by N,N-dimethylformamide (DMF) derivative compounds.

Abstrak :
Biodiesel was produced using three different alkali catalysts, namely KOH, NaOH and LiOH. The aim of the study was to determine which of these is the most effective as far as Fatty Acid Methyl Ester (FAME) yield is concerned in producing biodiesel from microalgae. Three different transesterification processes were considered; conventional, microwave-assisted and ultrasound-assisted. The study was able to show that NaOH and KOH generated far better FAME values compared to LiOH in all three transesterification processes. The introduction of microwave or ultrasound in the transesterification slightly increased the FAME yield by 5% and cut the reaction time by 50%. The best FAME yield was attained when the optimum process parameters were a methanol to oil ratio of 12:1; a catalyst load of 2% for NaOH and 3% for KOH; a reaction time of 12 minutes; and a microwave output power rate of 600 watts.

Abstrak :
Crude glycerol, a by-product of biodiesel production created via transesterification was pyrolyzed using a microwave heating technique in an oxygen-deficient environment. Coconut shell-based activated carbon was used as a catalyst to assist in the heat transfer and the cracking of glycerol into gaseous and liquid products. Investigation into the product yield was conducted by varying the pyrolysis temperature between 300°C and 800°C. The result revealed that liquid and gaseous pyrolysis products yield fell in the range of 15?42% and 55?82% by mass, respectively. An analysis of the liquid product using gas chromatography mass spectrometry (GC-MS) shows that glycerin (C3H8O3), methanamine (CH5N), and cyclotrisiloxane (C6H18O3Si3) were among the highest derived compounds in the pyrolyzed liquid yield. The derived pyrolysis products can potentially be used as alternative fuels in combustion systems.

Abstrak :
ABSTRAK Minyak nabati digunakan sebagai sebagai bahan baku untuk menghasilkan pelumas sebagai pengganti pelumas mineral karena tidak seperti pelumas mineral, minyak nabati adalah sumber daya alam berkelanjutan yang dapat terurai secara hayati dengan ekotoksisitas rendah. Biopelumas disintesis melalu transesterifikasi minyak kelapa dan minyak sawit mentah di mana gliserida bereaksi dengan alkohol dan katalis membentuk ester alkil asam lemak dan alkohol. Katalis heterogen dapat memberikan rute baru untuk produksi biopelumas yang ramah lingkungan. Katalis ini memberikan efisiensi konversi yang lebih tinggi daripada katalis homogen. Katalis heterogen partikulat dapat dengan mudah dipisahkan dari produk mengikuti reaksi yang memungkinkan katalis untuk digunakan kembali, menghasilkan lebih sedikit limbah, dan mengkonsumsi lebih sedikit energi. Oleh karena itu, dalam penelitian ini, kalsium hidroksida (Ca(OH)2) digunakan sebagai katalis heterogen, dengan proses kalsinasi. Untuk mengetahui karakterisasi katalis, dilakukan analysis XRD (X ray powder diffraction). Keberhasilan penelitian ini diperoleh dari sifat fisik dan kimia biopelumas menurut standar biopelumas melalui uji viskositas, densitas, titik nyala, titik awan, FTIR, dan GCMS. Hasil yield tertinggi yang diperoleh dari penelitian ini adalah 73.72% dengan minyak kelapa sebagai bahan baku, katalis Ca(OH)2 yang dikalsinasi, rasio methanol terhadap minyak 12:1, jumlah katalis 8% (terhadap minyak), waktu reaksi 3 jam, dan suhu reaksi 65°C.

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ABSTRACT Vegetable oil is used as a feedstock to produce lubricant as the substitute of mineral oil because unlike mineral oil, vegetable oil is a biodegradable and sustainable natural resource with low eco toxicity. Bio lubricant was synthesized by transesterification of coconut oil and crude palm oil in which a glyceride reacts with an alcohol in the presence of a catalyst forming fatty acid alkyl esters and an alcohol. Heterogeneous catalyst can provide new routes for the environmentally benign production of biolubricant. It provides higher conversion efficiency than a homogeneous catalyst. Particulate heterogeneous catalysts can be readily separated from products following reaction allowing the catalyst to be reused, generating less waste, and consuming less energy. Thus, in this research, calcium hydroxide (Ca(OH)2) is used as the heterogeneous catalyst, prepared using calcination. To find out the characterization of the catalyst, XRD (X ray powder diffraction) analysis is used. The success of this research is obtained by the physical and chemical properties of biolubricant according to commercial biolubricant standard through viscosity, density, flash point, FTIR, and GCMS test. The highest yield obtained from this research is 73.72% with coconut oil as the feedstock, calcined Ca(OH)2 catalyst, 12:1 methanol to oil ratio, 8% catalyst amount (in relation to oil), 3 hours reaction time, and 65C reaction temperature.

Abstrak :
Fatty acid metyl ester (FAME) merupakan bahan bakar terbarukan sebagai alternatif ramah lingkungan untuk bahan bakar fosil. Pada prinsipnya produksi FAME bergantung pada reaksi transesterifikasi asam lemak yang terkandung dalam minyak nabati atau limbah yang kaya asam lemak seperti minyak goreng bekas dengan alkohol rantai pendek dengan bantuan katalis. Pada penelitian ini telah berhasil disintesis nanopartikel MgO dan material core-shell MgO@SiO2 melalui metode sol-gel dengan surfaktan kationik (CTAB) sebagai pengarah struktur. Ke dua katalis tersebut sudah dikarakterisasi dengan FTIR, XRD, SEM, dan BET. Seluruh data karakterisasi mendukung terbentuknya nanopartikel MgO dan MgO@SiO2. Sintesis MgO@SiO2 tanpa surfaktan dan dengan menggunakan surfaktan CTAB, sesuai data SEM memperlihatkan bahwa core-shell MgO@SiO2 yang dihasilkan dengan surfaktan CTAB memiliki struktur yang lebih seragam. Katalis nanopartikel MgO dan katalis core-shell MgO@SiO2 diaplikasikan sebagai katalis utama dalam pembentukan FAME dari rekasi transesterifikasi minyak goreng bekas dengan alkohol rantai pendek, dan FAME yang dihasilkan dikarakterisasi dengan GC-MS. Hasil uji ke dua katalis, MgO dan MgO@SiO2 dalam menghasilkan FAME didapatkan bahwa persen yield menggunakan katalis MgO@SiO2 (72.58%) lebih besar dibandingkan dengan katalis MgO (50.55 %). ......Fatty acid methyl ester (FAME) is a renewable fuel as an environmentally friendly alternative to fossil fuels. In principle, the production of FAME depends on the transesterification reaction of fatty acids contained in vegetable oils or waste rich in fatty acids such as used cooking oil with short-chain alcohol with the help of a catalyst. In this study, MgO nanoparticles and MgO@SiO2 core-shell materials have been successfully synthesized through the sol-gel method with cationic surfactant (CTAB) as a structural guide. The two catalysts have been characterized by FTIR, XRD, SEM, and BET. All characterization data support the formation of MgO and MgO@SiO2 nanoparticles. Synthesis of MgO@SiO2 without surfactant and using CTAB surfactant, according to SEM data showed that the core-shell MgO@SiO2 produced with CTAB surfactant had a more uniform structure. MgO nanoparticle catalyst and core-shell MgO@SiO2 catalyst were applied as the main catalyst in the formation of FAME from the transesterification reaction of used cooking oil with short-chain alcohol, and the resulting FAME was characterized by GC-MS. In the test results for the two catalysts, MgO and MgO@SiO2 in producing FAME, it was found that the percent yield using the MgO@SiO2 catalyst (72.58%) was greater than the MgO catalyst (50.55%).

Abstrak :
Ketersediaan minyak bumi di dunia semakin menipis serta penggunaan bahan bakar fosil telah menyebabkan pencemaran lingkungan dan pemanasan global. Sehingga diperlukan pengembangan sumber energi terbarukan untuk menjadi subtitusi kebutuhan bahan bakar berbasis minyak bumi. Biodiesel dapat menjadi alternatif bahan bakar. Biodiesel adalah metil ester dapat disintesis melalui esterifikasi asam lemak misalnya adalah asam oleat yang banyak terkandung dalam minyak kelapa sawit. Proses esterifikasi memerlukan katalis asam. MIL-101(Cr) adalah metal organic framework yang tersusun dari logam kromium dan ligan asam tereftalat. MIL-101 (Cr) memiliki luas permukaan BET tinggi dan material ini memiliki potensi situs asam Lewis. Karenanya MIL-101 (Cr) dapat menjadi kandidat yang baik untuk katalis dalam esterifikasi asam lemak seperti asam oleat. Biodiesel juga bisa disintesis melalui transesterifikasi minyak nabati. Sehingga, dilakukan impregnasi logam Nikel pada MIL-101 (Cr) untuk meningkatkan kemampuan katalitiknya. Dalam penelitian ini hasil sintesis katalis MIL-101(Cr) dan Ni@MIL-101 (Cr) dilakukan karakterisasi dengan FTIR, XRD, SEM-EDS dan NH3-TPD. Hasil karakterisasi dapat diketahui struktur MIL-101 (Cr) sudah sesuai dan impregnasi Ni tidak merusak struktur MIL-101 (Cr). Hasil esterifikasi diperoleh untuk MIL-101 (Cr) memiliki persen konversi sebesar 96,06% sedangkan Ni@MIL-101 (Cr) memiliki persen konversi sebesar 12,95%. Untuk melihat metil ester yang terbentuk, hasil esterifikasi diuji GCMS. Dari hasilnya terbukti hampir semua asam lemak dapat terkonversi dengan katalis MIL-101 (Cr), dan masih banyak asam oleat yang belum terkonversi menjadi metil ester dengan katalis Ni@MIL-101 (Cr). Hasil transesterifikasi dengan minyak goreng kelapa sawit dapat dilihat terbentuknya 9-Octadecenoic acid, methyl ester dengan menggunakan katalis Ni@MIL-101 (Cr) dan tidak terbentuk metil ester dari asam oleat pada transesterifikasi menggunakan katalis MIL-101 (Cr). ......The availability of fossil fuel in the world is decreasing and the use of fossil fuels has caused environmental pollution and global warming. It is necessary to develop renewable energy sources to replace the need for fossil fuels. Biodiesel can be an alternative fuel. Biodiesel is a methyl ester that can be synthesized through the esterification of fatty acids, for example, oleic acid, which is abundant in palm oil. The esterification process requires an acid catalyst. MIL-101(Cr) is a metal organic framework composed of chromium metal and terephthalic acid ligands. MIL-101(Cr) has a high BET surface area and this material has potential of Lewis acid sites. Therefore MIL-101 (Cr) can be a good candidate for catalyst in the esterification of fatty acids such as oleic acid. Biodiesel can also be synthesized through plant based oil transesterification. Because of that, Nickel metal impregnation was carried out on MIL-101 (Cr) to increase its catalytic ability. In this study the results of the synthesis of MIL-101(Cr) and Ni@MIL-101(Cr) catalysts were characterized by FTIR, XRD, SEM-EDS and NH3-TPD. Based on the characterization results, the MIL-101 (Cr) structure is suitable and the Ni impregnation does not damage the MIL-101 (Cr) structure. The esterification results obtained for MIL-101 (Cr) have a conversion percentage of 96.06% while Ni@MIL-101 (Cr) has a conversion percentage of 12.95%. To see the methyl ester formed, the esterification results were tested by GCMS. The results show that almost all fatty acids can be converted with the MIL-101 (Cr) catalyst, and there is still a lot of oleic acid that has not been converted into methyl esters with the Ni@MIL-101 (Cr) catalyst. The results of transesterification with palm cooking oil can be seen from the formation of 9-Octadecenoic acid, methyl ester using Ni@MIL-101 (Cr) catalyst and no methyl ester from oleic acid in transesterification using MIL-101 (Cr) catalyst.