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"Penelitian pelumas dasar bio yang telah dilaksanakan di Departemen Teknik Kimia FTUI (DTK FTUI) menggunakan 3 tahapan proses pada rangkaian reaktor batch berpengaduk, memiliki kendala dalam pemurnian produk, pemisahan katalis dan panjangnya tahapan proses. Sedangkan proses esterifikasi menggunakan katalis asam dimana yang banyak digunakan adalah katalis homogen asam donor proton dalam pelarut organik, seperti H2SO4, HF, H3PO4 dan RSO3H, PTSA. Hanya saja, kataliskatalis homogen ini bersifat korosif, beracun dan sulit untuk dipisahkan dari produk. Disisi lain asam heteropoli (HPW) memiliki potensi tingkat keasaman yang tinggi, namun memiliki kelemahan dilihat dari rendahnya luas permukaan, dan kelarutan yang tinggi dalam sistem reaksi polar, sehingga untuk mengatasi hal tersebut HPW harus dijadikan katalis padat dengan cara menyisipkannya pada penyangga yang memiliki luas permukaan lebih besar, seperti zeolit. Untuk itu pada penelitian ini dilakukan proses esterifikasi asam oleat dengan oktanol menggunakan katalis asam padat, yaitu asam heteropoli yang disanggakan pada zeolit alam Lampung. Reaksi esterifikasi dilakukakan pada reaktor tumpak berpengaduk 100 mL yang dilengkapi dengan kondesor. Variasi kondisi reaksi yang dilakukan adalah pada suhu, putaran pengaduk, rasio mol asam oleat/alkohol dan berat katalis.Hasil karakterisasi memperlihatkan bahwa HPW terdispersi dengan baik pada zeolit tanpa merubah struktur zeolit. Kemudian dari hasil uji reaksi memperlihatkan bahwa penggunaan katalis HPW20/Z memiliki pengaruh terbesar pada konversi asam oleat (80.73%). Sedangkan konversi asam oleat dipengaruhi oleh jumlah katalis dan rasio mol asam oleat/oktanol. Sedangkan besarnya putaran pengadukkan dan perubahan suhu reaksi tidak meberikan perubahan signifikan terhadap konversi asam oleat. Produk ester yang didapat memiliki viskositas yang lebih encer dari peneliti sebelumnya di DTK-FTUI, sehingga dapat diaplikasikan pada kondisi tribologi yangberkecepatan tinggi dan rentang beban rendah seperti untuk pendingin dan pelumas pada mesin pembuatan logam dan rantai. Dari studi kinetika reaksi mengindikasikan bahwa reaksi esterifikasi yang dilakukan adalah berorde 2.

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Ester from vegetable oil as bio-based biolubricants have not yet attracted interest of researchers and industries. Whereas, up to now the utilisation of lubricants for automotives and industrial applications have reached 2.4 billion gallon per year, but bio-lubricants take only smallest portion, i.e. 0.1%. At Depatment of Chemical Engineering (DTK FTUI), synthesis of bio-based lubricants was carried out by 3 steps processes in batch reactor. The problems arised due to difficulties to separate products and catalysts and the step of processes was too long. On the other hand esterification is manufactured by using liquid mineral acid catalysts donor of proton, e.g H2SO4, HF, H3PO4 and RSO3H, PTSA. These conventional acid catalysts are not environmentally friendly, corrosive and induce disposal problems. The heteropoly acid (HPW) having strong Bronsted acid sites and high acidity could be used to replace conventional homogeneous catalysts, but HPW usually shows low catalytic activity due to low surface area, high solubility of HPW in water and polar solvent, thus HPW should be disperse on support with higher area, such as zeolit In this work, the esterification oleic acid with octanol was catalysed by acid solid catalysts, i.e HPW was supported on natural Lampung zeolit. Esterification was carried out in 100mL batch reactor equipped with condenser. Variation of reaction was performed on temperature, agitation, mol ratio of reactans and weight of catalysts.The result of characterization of catalysts shown that HPW was succesfully loaded on zeolite without change the structure of zeolit. Reaction results shown that HPW20/Z has the biggest influence to oleic acied convertion (80.73%). Whereas oleic acid convertion was influenced by weight of catalysts and mol ratio of reactants. But effect of agitation and change of temperature did not really give influence on convertion. The viscosity of ester in this work was less than the viscosity of biolubricants from the previous research at DTK-FTUI, thus it can be applied at high speed and low load regime of the tribological circumstances, such as a cooling lubricants compound for metalworking processes and chain lubrication. Study of kinetics shown the esterification reaction was second-order reaction."

"Kolom dislilasi vakum residu atmosfir jenis fuel-pitch merupakan salah satu alat yang terdapat pada industri pengolahan minyak mentah. Kolom distilasi vakurn jenis ini berfungsi untuk memfraksionasi umpan residu atrnosfir (yang tidak alcan terjadi jika proses fraksionasidilakukan pada kondisi tekanan atmosfir) menjadi distilat vakum dan residu vakum. Produk distilat vakum yang terdiri dari distilat vakurn berat (HVGO, heavy vacuum gas oil) dan distilat vakum ringan (LVGO, light vacum gas oil) digunakan sebagai umpan unit FCC (fluid catalytic cracking) sedangkan residu vakum dapat digunakan sebagai bahan baku aspal. Dalam perancangan kolom distilasi vakum residu atmosfir jenis fuel-pitch perlu diperhatikan pengaruh titik potong TBP antara distilat vakum dengan residu vakum dan kondisi tekanan serta temperatur didaerah flash terhadap spesifikasi produk yang Data kasus perancangan diambil dari crude assay minyak Arab, dengan asumsi peralatan utama dalam kolom terdiri dari material isian sebagai alat kontak perpindahan panas antara aliran cair dan uap, distributor cairan untuk mendistribusikan aliran cair diatas material isian agar merata dan talam chimney sebagai distributor aliran uap yang naik serta pengumpul cairan sebelum keluar kolom. Nilai jatuh tekanan dari masing-masing peralatan tersebut diasumsikan bertekanan 1 mma. Perhitungan perancangan proses dan rnekanis awal, yang diadaptasi dari pengalaman Watkins dan UOP (Universal Oil Product), memberikan hasil sebagai berikut : 1. Produk distilat vakum yarl dihasilkan sebesar 62,2396 dari keseluruhan umpan residu atmosfir pada titik potong TBP 1050°F dan temperatur daerah flash sebesar 730°F. 2. Kondisi operasi distilasi vakum residu atmosfir adalah kering. 3. Diameter dalam kolom utama adalah 29 ft. 4. Jenis material isian yang digunakan adalah jenis Glitsh grid pada daerah slop wax dan GRC (grid ring combination) pada daerah LVGO serta HVGO dengan tinggi masing-masing adalah 3 ft, 5 ft dan 3 ft."

"ABSTRAKBiodiesel adalah minyak diesel alternatif yang secara umum didefinisikan sebagai ester monoalkil dari minyak tanaman, lemak hewan, dan minyak jelantah. Biodiesel diperoleh dari hasil reaksi transterifikasi antara minyak dengan alcohol monohidrat dalam suatu katalis NaOH. Reaksi transterifikasi berlangsung 0,5-1 jam pada suhu sekitar 40°C hingga terbentuk dua lapisan. Lapisan bawah adalah gliserol dan lapisan atas metil ester. Penelitian ini pada intinya adalah mensimulasikan proses pembuatan biodiesel dengan menggunakan chemcad, dimana metode yang digunakan adalah metode hybrid. Pada penelitian ini akan digunakan senyawa trigliserida sebagai minyak nabatai (CPO) yang akan direaksikan dengan senyawa alkohol (methanol) dengan bantuan katalis basa (NaOH) dalam proses transesterifikasi. Transesterifikasi adalah tahap konversi dari trigliserida menjadi alkyl ester, melalui reaksi dengan alkohol, dan menghasilkan produk samping yaitu gliserol. Dalam penelitian ini, dimana akan menggunakan temperatur proses pada reaktornya sebesar 60°C dan pada tekana 200 Kpa, rasio molar Alkohol-Minyak 9:1 dengan katalis sebanyak 1% dari jumlah minyak yang diumpankan. Perhitungan awal ekonominya diperoleh dengan memperhatikan nilai CCF sebesar 1,30 maka bisnis dalam produksi biodiesel sangat feasible untuk dijalankan mengingat nilai CCF > 0,33."

"[ABSTRAKIndustri bahan bakar bio berkembang dengan cepat sebagai konsekuensi dari naiknya harga minya dan meningkatnya kepedulian terhadapa perubahan iklim global. Produksi biodiesel dari transesterifikasi minyak nabati saat ini merupakan rute yang utama untuk menghasilkan bahan bakar nabati (BBN) untuk mesin diesel. Namun, biodiesel memiliki viskositas tinggi, titik kabaut dan tuang yang tinggi, emisi nitrogen oksida (NOx) yang lebih tinggi, densitas energi rendah dan keausan injektor/mesin tinggi. Beberapa rute telah dicoba untuk mengurangi viskositas, seperti blending minyak nabati dengan bahan bakar diesel, mikroemulsi dengan alkohol, pirolisis dan hidrodeoksigenasi (HDO). Solar terbarukan melalui HDO dapat dihasilkan dari beragam bahan baku minyak nabati seperti minyak sawit dan minyak jarak pagar tanpa mengorbankan kualitas bahan bakar. Reaksi pembentukan solar terbarukan melalui HDO minyak nabati melibatkan katalis untuk menurunkan energi aktivasi reaksi dan meningkatkan selektifitasnya. Jenis katalis yang digunakan didalam studi ini adalah katalis berbasi Pd dan berbasis NiMo yang disanggakan pada ZAL atau C. Metode microwave polyol process (MP) cocok untuk preparasi katalis berbasis Pd sedangkan metode rapid cooling (RC) cocok untuk preparasi katalis berbasis NiMo. HDO asam oleat sebagai senyawa model, minyak sawit dan minyak jarak pagar dilakukan pada suhu 375°C dan 400°C dengan tekanan H2 15 bar didalam reaktor autoclave 250 ml semibatch berpengaduk. Didalam HDO, katalis Pd/ZAL-1 selektif terhadap jalur dekarboksilasi sedangakan katalis NiMo/ZAL selektif terhadap jalur dekarboksilasi dan dekarbonilasi katalitik. Soalr terbarukan yang dihasilkan dari HDO memiliki densitas dan viskositas yang sesuai sesuai dan indeks setana yang lebih tinggi disertai dengan kesetaraan dalam kualitasnya dengan solar komersial turunan minyak bumi namun sedikit lebih rendah daripada solar terbarukan komersial (NExBTL®).;

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ABSTRACTThe biofuels industry is growing rapidly as a result of high petroleum prices and increasing concerns about global climate change. Biodiesel production from trans-esterification of vegetable oils is currently the primary route for production of diesel engine biofuels from vegetable oils. However, biodiesel still has higher viscosity, higher cloud point and pour point, higher nitrogen oxides (NOx) emissions, lower energy density, and higher injector/engine wear. Several routes have been tried for reducing this viscosity, such as diluted vegetable oil with diesel fuel, microemulsification with alcohols, pyrolysis and hydrodeoxygenation (HDO). Renewable diesel through HDO can be produced from many kind of vegetable oil feeed stock such as palm oil (edible oil) and jatropha curcas (non-edible oil)without compromising fuel quality. Forming reaction of renewable diesel through HDO vegetable oil involves catalyst to decrease the activation energy of the reaction and increase its selectivity. The type of catalyst used in this study is Pd and NiMo supported on ZAL or C. Microwave polyol method (MP) is suitable for preparation of Pd-based catalyst while rapid cooling method (RC) is suitable for preparation of NiMo-based catalyst. The HDO of oleic acid as model compound, palm oil and jatropha curcas oil were carried out at temperature of 375°C and 400°C with H2 pressure of 15 bar in a 250 mL semibatch stirred autoclave reactor. In HDO, Pd/ZAL-1 catalyst was selective to decarboxylation route while NiMo/ZAL was selective to decarboxylation and catalytic decarbonilation. Renewable diesel synthesized through HDO have suitable density and viscosity and quite high cetane index with similar in their quality with comercial diesel derived from crude oil but slightly lower than comercial renewable diesel (NExBTL®).;The biofuels industry is growing rapidly as a result of high petroleum prices and increasing concerns about global climate change. Biodiesel production from trans-esterification of vegetable oils is currently the primary route for production of diesel engine biofuels from vegetable oils. However, biodiesel still has higher viscosity, higher cloud point and pour point, higher nitrogen oxides (NOx) emissions, lower energy density, and higher injector/engine wear. Several routes have been tried for reducing this viscosity, such as diluted vegetable oil with diesel fuel, microemulsification with alcohols, pyrolysis and hydrodeoxygenation (HDO). Renewable diesel through HDO can be produced from many kind of vegetable oil feeed stock such as palm oil (edible oil) and jatropha curcas (non-edible oil)without compromising fuel quality. Forming reaction of renewable diesel through HDO vegetable oil involves catalyst to decrease the activation energy of the reaction and increase its selectivity. The type of catalyst used in this study is Pd and NiMo supported on ZAL or C. Microwave polyol method (MP) is suitable for preparation of Pd-based catalyst while rapid cooling method (RC) is suitable for preparation of NiMo-based catalyst. The HDO of oleic acid as model compound, palm oil and jatropha curcas oil were carried out at temperature of 375°C and 400°C with H2 pressure of 15 bar in a 250 mL semibatch stirred autoclave reactor. In HDO, Pd/ZAL-1 catalyst was selective to decarboxylation route while NiMo/ZAL was selective to decarboxylation and catalytic decarbonilation. Renewable diesel synthesized through HDO have suitable density and viscosity and quite high cetane index with similar in their quality with comercial diesel derived from crude oil but slightly lower than comercial renewable diesel (NExBTL®)., The biofuels industry is growing rapidly as a result of high petroleum prices and increasing concerns about global climate change. Biodiesel production from trans-esterification of vegetable oils is currently the primary route for production of diesel engine biofuels from vegetable oils. However, biodiesel still has higher viscosity, higher cloud point and pour point, higher nitrogen oxides (NOx) emissions, lower energy density, and higher injector/engine wear. Several routes have been tried for reducing this viscosity, such as diluted vegetable oil with diesel fuel, microemulsification with alcohols, pyrolysis and hydrodeoxygenation (HDO). Renewable diesel through HDO can be produced from many kind of vegetable oil feeed stock such as palm oil (edible oil) and jatropha curcas (non-edible oil)without compromising fuel quality. Forming reaction of renewable diesel through HDO vegetable oil involves catalyst to decrease the activation energy of the reaction and increase its selectivity. The type of catalyst used in this study is Pd and NiMo supported on ZAL or C. Microwave polyol method (MP) is suitable for preparation of Pd-based catalyst while rapid cooling method (RC) is suitable for preparation of NiMo-based catalyst. The HDO of oleic acid as model compound, palm oil and jatropha curcas oil were carried out at temperature of 375°C and 400°C with H2 pressure of 15 bar in a 250 mL semibatch stirred autoclave reactor. In HDO, Pd/ZAL-1 catalyst was selective to decarboxylation route while NiMo/ZAL was selective to decarboxylation and catalytic decarbonilation. Renewable diesel synthesized through HDO have suitable density and viscosity and quite high cetane index with similar in their quality with comercial diesel derived from crude oil but slightly lower than comercial renewable diesel (NExBTL®).]"

"Hydrodeoxygenation of palm oil and Jatropha curcas oil over NiMo/ZAL (nickel molybdenum/zeolit alam Lampung) catalyst was investigated under temperatures of 375°C and 400°C and H2 pressure of 15 bar in a semibatch stirred autoclave reactor. NiMo/ZAL catalyst was prepared using a rapid cooling method. NiMo/ZAL characterization revealed a crystal size of 70.07 nm, surface area of 12.25 m2/g, and pore size and pore volume of 9.83 Å and 0.0062 cm3/g, respectively. The hydrodeoxygenation removal pathway of palm oil and Jatropha curcas oil over NiMo/ZAL catalyst was primarily achieved through decarboxylation. Under hydrogen pressure of 15 bar and temperature of 375°C, palm oil and Jatropha curcas oil can be converted into paraffin chains (from n-C15 up to n-C18) by a decarboxylation reaction that produces water, methane, and COx gases as byproducts and contains some undesirable reactions. These byproducts can produce alkene bonds that form chains different from those in conventional diesel fuel. The conversion was 80.87%, selectivity was 52.78%, and yield was 45.66%. The hydrodeoxygenation reaction catalyzed by NiMo/ZAL catalyst was found to be suitable for removing oxygen and producing paraffin chains; this increased the heating value and stability of renewable diesel fuel."