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Abstrak :
Saat ini, sumber bahan bakar utama masih berasal dari bahan bakar fosil, salah satunya adalah avtur, yang ketersediannya masih terbatas dan meningkatkan emisi gas rumah kaca. Kondisi ini mendorong penggantian avtur menjadi bioavtur, yang merupakan salah satu energi berkelanjutan yang ramah lingkungan. Pada penelitian ini, bioavtur disintesis melalui reaksi hidrodeoksigenasi dan perengkahan katalitik dari senyawa model asam oleat menggunakan katalis NiMo/Zeolit. Hidrodeoksigenasi dilakukan pada kondisi operasi yang seragam yaitu pada suhu 375°C, pada tekanan hidrogen 15 bar selama 2,5 jam. Rantai hidrokarbon pada hasil hidrodeoksigenasi yang dianggap masih panjang direngkah kembali melalui reaksi perengkahan katalitik selama 1,5 jam. Reaksi ini dilakukan pada tiga variasi suhu, yaitu 360, 375, dan 390°C. Karakteristik produk cair dibagi menjadi dua macam, yaitu karakteristik kimia, berupa bilangan asam, FTIR, dan GC-MS dan karakteristik fisik, berupa uji densitas dan viskositas. Bioavtur yang telah tersintesis melalui perengkahan katalitik ini telah memenuhi spesifikasi avtur komersial, kecuali bilangan asam dengan suhu optimum pada 375°C. Pada kondisi ini, NiMo/Zeolit mampu melakukan sintesis bioavtur dengan yield 34,77, selektivitas 36,43 dan konversi 84,30. Nilai persentase yield dan selektivitas yang terbilang masih rendah disebabkan oleh kinerja katalis yang belum optimal. Sedangkan konversi yang tinggi, disebabkan oleh cukup tingginya suhu perengkahan katalitik. ......Currently, fossil fuels are still the primary source of fuel. As has been known, fossil fuel especially aviation fuel is limited resources and can increase greenhouse gas emissions. This condition encourages avture replacement efforts into bioavtures fuel. In this research, bioavture is synthesized through hydrodeoxygenation and catalytic cracking from oleic acid as model compound using NiMo Zeolite catalyst. Hydrodeoxygenation carried out under operating conditions at temperature of 375°C, under 15 bar pressure and for 2.5 hours. The chain of hydrocarbons from the result of hydrodeoxygenation has been cracked by catalytic cracking reaction for 1.5 hours. Variation operating condition used are 360, 375, and 390°C. The liquid product is tested its chemical characteristic, ie acid number, FTIR and GC MS and its physical characteristics, ie density test and viscosity. Bioavtur that synthesized by catalytic cracking have met the specifications of bioavtur, except the acid number with optimum temperature at 375oC. These conditions with NiMo Zeolite activated led to dominant yield of 34.77 , selectivity of 36.43, and conversion of 84.30. Percentage of yield and selectivity of bioavtur are still low caused by performance of catalyst that is still can not optimum. Whereas, high percentage conversion caused by high temperature used for catalytic cracking.

Abstrak :
Penyakit akibat infeksi bakteri masih menjadi masalah di masyarakat. Salah satu cara untuk mengatasi infeksi tersebut dengan menggunakan antibiotika. Namun, beberapa penelitian melaporkan banyak bakteri telah resisten terhadap antibiotika tertentu. Penelitian ini dilakukan untuk memodifikasi asam risinoleat dan mereaksikannya dengan asam galat untuk menghasilkan produk yang memiliki aktivitas antibakteri. Esterifikasi dilakukan dengan mereaksikan asam risinoleat dan oleat dengan metanol serta adanya penambahan katalis asam sulfat. Metil ester yang terbentuk selanjutnya dioksidasi menggunakan H2O2 30%. Tahap berikutnya adalah reaksi esterifikasi Steglich dengan asam galat. Tahapan reaksi dipantau menggunakan KLT. Produk hasil reaksi dikarakterisasi menggunakan FTIR, NMR dan UV, setelah dilakukan pemurnian dengan kromatografi kolom. Dari tahapan sintesis fenolipid didapatkan produk berupa fenolipid metil risinoleat, fenolipid oksida risinoleat, dan fenolipid oksida metil oleat. Hasil karakterisasi FTIR produk fenolipid didapatkan peningkatan intensitas pita serapan gugus -OH pada rentang bilangan gelombang 3500 cm-1 sampai 3200 cm-1 yang menunjukkan adanya pertambahan gugus -OH. Ciri khas serapan lainnya terdapat serapan -C-O ester aromatik pada bilangan gelombang 1300 cm-1 sampai 1000 cm-1. Selain itu, terdeteksi serapan infra merah gugus C=C aromatik pada bilangan gelombang 1625 cm-1 samapai 1500 cm-1. Produk fenolipid yang diperoleh diuji tosisitasnya terhadap Daphnia magna. Hasil uji menunjukkan bahwa senyawa fenolipid memiliki toksisitas yang sangat tinggi dengan nilai LC50 <100 ppm. Produk hasil sintesis jugdiuji aktivitas antibakterinya terhadap Escherichia coli dan Staphylococcus aureus. Hasil uji tersebut menunjukkan bahwa produk fenolipid mengalami sedikit peningkatan aktivitas dibandingkan senyawa prekursor yang ditunjukkan pada nilai zona inhibisin namun masih tergolong memiliki aktivitas lemah ......Diseases caused by bacterial infections are still a problem in society. One way to treat the infection is to use antibiotics. However, some studies report that many bacteria have become resistant to certain antibiotics. This research was conducted to modify ricinoleic acid and react with gallic acid to produce a product that has antibacterial activity. Esterification was carried out by reacting ricinoleic and oleic acids with methanol with the addition of sulfuric acid as a catalyst. The methyl ester formed was then oxidized using 30% H2O2. The Steglich esterification reaction with gallic acid. The reaction steps were monitored using TLC. The reaction products were characterized using FTIR, NMR, and UV after purification by column chromatography. From the phenolipid synthesis stage, the products obtained were phenolipid methyl ricinoleate, phenolipid ricinoleic oxide, and phenolipid oxide methyl oleate. The results of FTIR characterization of phenolipid products showed an increase in the intensity of the absorption band of the-OH group in the range of wave numbers from 3500 cm-1 to 3200 cm-1, which indicated an increase in the-OH group. Another characteristic of absorption is the absorption of-C-O aromatic esters at wave numbers of 1300 cm-1 to 1000 cm-1. In addition, infrared absorption of the aromatic C=C group was detected at wave numbers from 1625 cm1 to 1500 cm-1. The phenolipid products obtained weres examined for their toxicity against Daphnia magna. The results showed that all phenolipid compounds were categorized as very strong toxicity with an LC50 value of <100 ppm. The synthesized products were also tested for their antibacterial activity against Escherichia coli and Staphylococcus aureus. The test results showed that the phenolipid product experienced a slight increase in activity compared to the precursor compound, indicated by the inhibitory zone value, but was still classified as having weak activity.

Abstrak :
Asam oleat atau asam Z-Δ9-oktadekanoat diketahui sebagai salah satu asam lemak yang memiliki toksisitas yang rendah dan memiliki aktivitas antimikroba, sehingga dikembangkan penelitian untuk mendapatkan senyawa turunan dari asam oleat dan mengetahui bioaktivitasnya. Pada penelitian ini, dilakukan sintesis turunan asam amino dari senyawa asam oleat dengan reaksi esterifikasi dan amidasi, lalu dikarakterisasi dengan KLT dan FTIR. Asam oleat diesterifikasi dengan katalis basa, kemudian diamidasi dengan asam amino glisin dan asam amino fenilalanin. Setelahnya, dilakukan uji pendahuluan BSLT dan uji antimikroba dengan metode difusi cakram. Dari hasil penelitian didapatkan % kematian dari konjugat asam oleat, glisin oleat, dan fenilalanin oleat. Asam Oleat dengan konsentrasi 16,6 ppm memiliki % kematian paling tinggi yaitu 35%. Adapun hasil uji antimikroba konjugat asam oleat, glisin oleat, dan fenilalanin oleat tidak memiliki aktivitas antimikroba terhadap bakteri kulit gram positif yaitu Staphylococcus aureus dan bakteri kulit gram negatif yaitu Escherichia coli. ......Oleic acid or Z-Δ9-octadecanoic acid is known as a fatty acid that has low toxicity and antimicrobial activity, so research was developed to obtain compounds derived from oleic acid and determine its bioactivity. In this research, the synthesis of amino acid derivatives from oleic acid compounds by esterification and amidation reactions was carried out, then characterized by TLC and FTIR. Oleic acid is esterified with a base catalyst, then amides with the amino acid glycine and the amino acid phenylalanine. After that, a preliminary BSLT test and an antimicrobial test using the disc diffusion method were carried out. From the results of the study obtained % of deaths from conjugates of oleic acid, glycine oleic, and phenylalanine oleate. Oleic acid with a concentration of 16.6 ppm had the highest % mortality, namely 35%. The results of the antimicrobial conjugate test of oleic acid, glycine oleic, and phenylalanine oleate did not have antimicrobial activity against gram-positive skin bacteria, namely Staphylococcus aureus and gram-negative skin bacteria, Escherichia coli.

Abstrak :
Deep Eutectic Solvent (DES) adalah pelarut ramah lingkungan yang tidak mudah menguap dan dapat digunakan sebagai pelarut ekstraksi untuk menghilangkan asam oleat dari minyak kelapa sawit. Ini disebabkan oleh rendahnya tingkat toksisitas dan tidak memengaruhi kandungan antioksidan dari minyak kelapa sawit. Penelitian ini bertujuan untuk mencapai pemisahan yang efisien dari asam oleat dari minyak kelapa sawit dengan menyaring DES yang melarutkan asam oleat paling tinggi, menentukan kondisi optimal dalam proses pembekuan fraksional, dan menganalisis kandungan minyak kelapa sawit dalam DES menggunakan kromatografi gas serta kandungan DES dalam minyak kelapa sawit menggunakan metode titrasi Karl-Fischer. DES terbaik ditentukan dari hasil penapisan yang memiliki tingkat solubilitas tertinggi, yaitu kolin klorida (HBA) dan 1,2-oktandiol (HBD) dengan rasio molar 1:7 yang memiliki efisiensi ekstraksi sebesar 68,3%. Dalam proses pembekuan fraksional, sampel diuji dengan variasi suhu pendinginan sebesar 5°C, 10°C, dan 14°C. Dari hasil yang didapatkan, DES terbaik memiliki persentase recovery kandungan asam oleat dalam DES setelah pendinginan sebesar 53,33%. ......Deep Eutectic Solvent (DES) is a non-volatile, environmentally friendly solvent that can be used as an extraction solvent to remove oleic acid from palm oil. This is due to its low toxicity and does not affect the antioxidant content of palm oil. This study aims to achieve efficient separation of oleic acid from RBD palm olein by screening DES that dissolves the highest oleic acid, determining the optimal conditions in the fractional freezing process, and analyzing the palm oil content in DES using gas chromatography as well as the DES content in palm oil using the Karl-Fischer titration method. The best DES was determined from the screening stage that had the highest solubility level, namely choline chloride (HBA) and 1,2-octanediol (HBD) with a molar ratio of 1:7 which had an extraction efficiency of 68.3%. In the fractional freezing method, the samples were tested with cooling temperature variations of 5°C, 10°C, and 14°C. From the results obtained, the best DES has a recovery percentage of oleic acid content in DES after fractional freezing of 53.33%.

Abstrak :
The present study investigates the aqueous stability of polyethylene glycol and oleic acid- based anionic surfactants through the dynamic light scattering (DLS) and zeta potential methods, for application in enhanced oil recovery (EOR). Polyethylene glycol dioleate sulfonate (PDOS) surfactant solutions were prepared in concentrations of 0.05, 0.1, 0.3, 0.5, and 1 wt% in deionized water. Aqueous stability of PDOS was assessed by measuring the droplet size over five days, using nano particle analyzer HORIBA SZ-100 at 25oC. Results show that good aqueous stability of PDOS was achieved at concentrations of 0.1 to 1 wt%, but with the droplet size becoming unstable at the lowest concentration of 0.05 wt%. The polydispersity indices were classified into polydisperse distribution type recorded as 0.3 to 0.5 at concentrations of 0.05 and 0.1 wt% and 0.2 at concentrations of 0.3 to 1 wt%. The critical micelle concentration (CMC) of PDOS was 0.3% and the interfacial tension of PDOS surfactant above the CMC was around 10-3 dyn/cm. The zeta potential of PDOS surfactant without the addition of salt in concentrations of 0.05, 0.1, 0.3, 0.5, and 1 wt% was highly stable up to -96.8, -90.5, -89.6, -82.3, and -64.4 mV, respectively. With the addition of salt they were moderately stable at a concentration of 1 wt%. The conductivity increased with increasing concentration. The zeta potential of PDOS with the addition of salt was moderately stable in a concentration of 1%. Although PDOS with concentration of 0.05% showed a high value of zeta potential with the addition of salt, there is no guarantee that the PDOS surfactant solution will be stable for five days.

Abstrak :
Pada penelitian ini, asam oleat diesterifikasi dengan dry metanol dan katalis HCl pekat dengan menggunakan refluks selama 6 jam pada suhu 60°C. Metil oleat yang terbentuk kemudian diamidasi dengan asam amino glisina dan fenilalanina yang dibantu dengan pelarut assetonitril. Selain itu, dilakukan juga amidasi langsung dari asam oleat dengan bantuan disikloheksilkarbodiimida (DCC) sebagai agen pengopling selama 2 jam pada suhu 0°C. Produk lipoamida yang terbentuk di identifikasi dengan KLT, di purifikasi dengan kromatografi kolom, dan di karakterisasi dengan FTIR. Aktivitas antifungi amida asam oleat juga ditentukan dengan metode difusi cakram terhadap Candida albicans. Hasil uji menunjukkan bahwa N-oleilglisina ACN memiliki aktivitas antifungi dengan kategori sedang, N-oleilfenilalanina ACN berkategori sedang, N- oleilglisina DCC tidak ada aktivitas, dan N- oleilfenilalanina DCC berkategori sedang. ......In this study, oleic acid was esterified with dry methanol and concentrated HCl catalyst using reflux for 6 hours at 60oC. The methyl oleate formed then amidated by glycine and phenylalanine using acetonitrile as a solvent. In addition, direct amidation of oleic acid was also carried using dicyclohexylcarbodiimide (DCC) as a coupling agent for 2 hours at 0oC temperature. The formed lipoamide product was identified by TLC, purified by column chromatography, and characterized by FTIR. The antifungal activity of oleic acid amide was also determined by disc diffusion method against Candida albicans. The result showed that N- oleylglycine ACN has moderate antifungal activity, N-oleylphenylalanine ACN has moderate category, N-oleylglycine DCC has no activity, and N-oleylphenylalanine DCC has moderate category.

Abstrak :
Penelitian ini dilakukan untuk mempelajari aktivitas katalitik dari katalis silika-organosilika terfungsionalisasi sulfonat yang disintesis berdasarkan metode sol-gel, pada reaksi esterifikasi antara asam oleat dengan neopentil glikol. Aktivitas katalitiknya dibandingkan dengan empat jenis katalis lain, yaitu katalis SBA-15, SBA-15-PrSO3H dengan dua variasi komposisi, dan Ph-PMO-PrSO3H. Pengujian dilaksanakan pada kondisi reaksi yang sama untuk semua jenis katalis, yaitu dengan rasio molar reaktan neopentil glikol : asam oleat 4:1, suhu reaksi 150 oC, jumlah katalis 3%, dan waktu reaksi selama 120 menit. Hasil dari penelitian didapatkan katalis silika-organosilika terfungsionalisasi sulfonat menghasilkan persen konversi produk yang tertinggi, yaitu 71,09%. Selain itu, dilakukan pula variasi rasio molar reaktan, persen jumlah katalis, dan waktu reaksi untuk mengetahui kondisi optimum reaksi. Didapatkan kondisi optimum dari reaksi adalah rasio molar reaktan neopentil glikol : asam oleat 4:1 dengan jumlah katalis 5% dan waktu reaksi selama 300 menit menghasilkan persen konversi produk 87,14%. Dari pengujian daya daur ulang katalis diketahui bahwa katalis silika-organosilika terfungsionalisasi sulfonat memiliki daya daur ulang yang baik untuk tiga kali reaksi, masing-masing dengan persen konversi asam oleat 87,14%, 87,09%, dan 86,73%. Hal ini juga dikonfirmasi oleh karakterisasi FTIR katalis yang tidak menunjukkan adanya gugus fungsi yang hilang dibandingkan dengan katalis sebelum digunakan di reaksi. ......This research was conducted to study the catalytic activity of a sulfonate functionalized silica-organosilicate catalyst synthesized based on the sol-gel method, in the esterification reaction between oleic acid and neopentyl glycol. The catalytic activity was compared to four other types of catalysts, namely SBA-15, SBA-15-PrSO3H with two variations of composition, and Ph-PMO-PrSO3H. The test was carried out under the same reaction conditions for all types of catalysts, namely with a molar ratio of neopentyl glycol reactants: oleic acid 4:1, reaction temperature of 150 oC, amount of catalyst 3%, and reaction time of 120 minutes. The results of the study showed that the sulfonate functionalized silica-organosilica catalyst produced the highest percentage of product conversion, namely 71,09%. In addition, variations in the molar ratio of the reactants, the percent amount of catalyst, and reaction time were also carried out to determine the optimum conditions for the reaction. The optimum conditions for the reaction were the molar ratio of reactants neopentyl glycol : oleic acid 4:1 with 5% catalyst and 300 minutes of reaction time to produce a product conversion percentage of 87,14%. From the catalyst recycling test it was found that the sulfonate functionalized silica-organosilica catalyst had good recyclability for three reactions, with percent oleic acid conversion of 87,14%, 87,09% and 86,73%, respectively. This was also confirmed by the FTIR characterization of the catalyst which did not show any loss of functional groups compared to the catalyst before being used in the reaction.

Abstrak :
Batuan sekismika dengan jenis batuan spodumene dan lepidolite adalah batuan yang mengandung logam-logam berharga di dalamnya, dimana salah satu dari unsur logam-logam berharga tersebut terdapat unsur kandungan litium. Penelitian ini dilakukan untuk melakukan benefisiasi atau peningkatan terhadap kadar litium yang terkandung dalam batuan sekismika dengan tahapan proses hidrometalurgi menggunakan proses froth flotasi. Dalam percobaan ini bongkahan besar batuan pertama kali akan melalui tahapan crushing dan milling untuk menjadikan batuan menjadi bentuk serbuk halus hingga berukuruan -100 mesh. Kemudian, proses hidrometalurgi dimulai menggunakan tahapan flotasi dengan menggunakan kolektor berupa campuran dodecylamine dengan oleic acid dan frother berupa pine oil. Pada tahapan proses hidrometalurgi ini dilakukan beberapa variasi diantaranya adalah variasi pH (8, 9, 10 dan 11), rasio persen solid (2%, 4%, 6%, dan 8%), dan waktu (5, 10, 15, 20, dan 25 menit). Variasi tersebut dilakukan untuk mengetahui variabel yang menghasilkan persen recovery optimum dari benefisiasi litium. Sampel dan hasil percobaan ini dianalisis menggunakan ICP untuk mengetahui konsentrasi litium setelah dilakukan proses benefisiasi dengan metode hidrometalurgi tersebut. Hasil dari proses benefisiasi kadar litium dengan perolehan persen recovery terbaik terjadi pada variasi waktu 5 menit dan 15 menit, kemudian dengan variasi variabel 4% solid dan 6% solid, serta variabel pH terbaik pada pH 9. Nilai persen recovery optimum pada penelitian ini adalah 82,35% yang bersumber dari larutan terapung pada hasil flotasi dengan variasi waktu 15 menit, 6% solid, dan pH 9 ......Mica Schist rocks with spodumene and lepidolite types are rocks that contain precious metals in them, where one of the precious metal elements contains lithium. This research was conducted to perform beneficiation or increase the level of lithium contained in mica schisc rocks with the process of the hydrometallurgy using the froth flotation process. In this experiment, boulder of mica schisc rocks will first go through the stages of crushing and milling to turn the mica schisc rocks into a fine powder up to -100 mesh in size. Then, the hydrometallurgical process was started using a flotation step using a collector in the form of a mixture of dodecylamine with oleic acid and pine oil as the frother. During this step of the hydrometallurgical process, several variations were carried out including variations in pH (8, 9, 10 and 11), percent solid ratio (2%, 4%, 6%, and 8%), and time (5, 10, 15, 20 , and 25 minutes) to find out in which variation the highest percent recovery from the lithium beneficiation can occur. The sample and the results of this experiment are characterized by the ICP process to determine the lithium content after the beneficiation process using the hydrometallurgical method is carried out. The results of the lithium beneficiation process with the best percent recovery gain occurred at a time variation of 5 minutes and 15 minutes, then with a variable variation of 4% solid and 6% solid also the best pH variable at pH 9. The optimum percent recovery value in this study was 82.35% which was sourced from the floating solution on the flotation results with variations in time of 15 minutes, 6% solid, and pH 9

Abstrak :
Indonesia merupakan salah satu negara beriklim tropis dan memiliki kelembaban udara tinggi. Kondisi ini memicu pertumbuhan Candida albicans dan menyebabkan infeksi jamur. Berbagai penelitian telah dilakukan untuk menemukan senyawa kandidat antifungi berbasis sumber daya alam seperti tumbuhan dan memiliki efek samping yang rendah, terutama turunan lipid seperti senyawa lipoamida. Pada penelitian ini, asam oleat telah diesterifikasi dengan dry methanol menggunakan katalis asam HCl menghasilkan metil oleat. Selanjutnya ikatan rangkap pada metil oleat dioksidasi menggunakan KMnO4 encer dalam suasana basa dan suhu 25oC. Keberhasilan oksidasi ditunjukkan dari penurunan bilangan iod dari 79,56 mg/g menjadi 4,82 mg/g. Selanjutnya, dilakukan reaksi amidasi dengan asam amino glisina dan fenilalanina. Produk – produknya diidentifikasi dengan Kromatografi Lapis Tipis (KLT), dan dikarakterisasi menggunakan FT-IR (Fourier Transform Infra Red). Hasil FTIR lipoamida menunjukkan adanya overlapping gugus - OH dan -NH stretch pada bilangan gelombang sekitar 3200 – 3500 cm-1, gugus C=O amida pada 1652 cm-1 dan 1666 cm-1, serta gugus C-N stretch pada 1326 cm-1dan 1248 cm-1 untuk lipoamida – glisin dan lipoamida – fenilalanin. Produk lipoamida tidak terdeteksi memiliki aktivitas antifungi terhadap Candida albicans pada konsentrasi 1000 ppm. ......Indonesia is a country with tropical climate and has high humidity. This condition stimulates the growth of Candida albicans and causes a fungal infection. Various studies have been carried out to obtain candidate compounds for antifungal based on natural resources such as plants and have low side effects, especially lipid derivatives such as lipoamide compounds. In this research, the esterification of oleic acid with dry methanol was carried out using HCl as an acid catalyst to produce methyl oleate (MO). Furthermore, the double bond in MO is oxidized using dilute KMnO4 under alkaline conditions at 25oC low temperature. The success of oxidation was indicated by the decrease in the iodine value from 79,56 mg/g to 4,82 mg/g. Furthermore, the oxidized methyl oleate was amidated with the amino acid glycine and phenylalanine. The products obtained were identified by Thin Layer Chromatography (TLC) and characterized by FT- IR. FTIR results of lipoamides show overlapping between -OH and -NH stretch around 3200 – 3500 cm-1, C=O amide at 11652 cm-1 and 1666 cm-1, and C-N stretch at 1326 cm- 1 and 1248 cm-1 for lipoamide – glycine and lipoamide – phenylalanine. The antifungal activity test results showed that the lipoamide products were not detected to have antifungal activity against Candida albicans at 1000 ppm.