Judul: The Effect of Variation in Temperature and Duration on Deoxygenation and Cracking Reaction of RPO in Bioavtur
Abstrak: Vegetable oils can be converted into bioavtur because they have triglycerides that can be converted through deoxygenation and cracking into bioavtur hydrocarbon. Refined Palm Oil (RPO) is also vegetable triglyceride that may be converted into bioavtur by similar mechanism. This study aims to convert RPO into hydrocarbons equal to avtur through deoxygenation and cracking with various temperature and reaction duration. In the preliminary research, RPO was made from degumming process of CPO, heated with solid catalyst NiMo in a reactor at temperature of 300, 400 and 450 oC, with addition of hydrogen at pressure of 50 bar and stirring for 5 h with sampling every hour to obtain the suitable temperature conditions. At principal research, the same reaction was conducted at selected temperature conditions with sampling every 30 minutes after initial heating for 1 h. Observation was conducted for parameters density, phase change at low temperatures (-15 and -55 oC), GC-MS and FTIR analysis. Preliminary research showed that only at temperature of 450 oC, the product had liquid phase up to -55 oC and the density equal to jet fuel. At this temperature condition (450 oC ), the results showed that the best deoxygenation and cracking reaction was at pressure of 50 bar, in 3 h duration. The physical properties of the products were having the best deoxygenation reaction, having similar properties with aviation fuel, and density of 0.8105 g/cm3, still on liquid phase at low temperature up to -55 oC with the composition of mostly C7 - C12 hydrocarbons.
Keyword: bioavtur, refined palm oil, deoxygenation, cracking

Judul: Sintesis Biohidrokarbon dari Minyak Goreng Sawit Menggunakan Reaktor Pirolisis dengan Variasi Suhu
Abstrak: Sintesis biofuel dari minyak nabati menggunakan reaktor pirolisis dipelajari sebagai alternatif proses biohidrokarbon yang memiliki sifat mirip dengan bahan bakar fosil. Penelitian ini menggunakan minyak goreng sawit sebagai bahan baku yang direaksikan pada suhu yang dinaikkan secara bertahap mulai dari 225, 250, 275, dan 300°C serta menggunakan zeolit sebagai katalis. Senyawa volatil yang terkondensasi dikumpulkan berdasarkan fraksi dan dianalisa warna, densitas, viskositas kinematik, kadar air, titik tuang, nilai kalor, dan komposisi senyawa volatil berdasarkan analisa GCMS. Minyak goreng sawit sebagai bahan baku memiliki kadar air 0.095% (b/b), viskositas kinematik 41.25 mm2/s, titik tuang 20°C, dan nilai kalor 39.93 MJ/Kg. Fraksi biohidrokarbon pada berbagai temperatur memiliki warna merah sampai kuning cerah, fase cair dan hanya fraksi 300°C yang memiliki fraksi padat. Densitas biohidrokarbon berkisar antara 0.8452 – 0.8527 g/cm3(40°C), viskositas kinematik 3.0726 – 3.8137 mm2/s, kadar air 0.0801 - 0.1878% (b/b), dan titik tuang 4 - 22°C. Densitas, viskositas kinematik, dan titik tuang dari fraksi suhu 225 - 275°C memenuhi standar nasional biodiesel dan solar. Senyawa volatil terdiri atas asam dekanoat, asam undekanoat, asam dodekanoat, heptadekena, heptadekana, asam tetradekanoat, dan asam heksadekanoat. Komponen senyawa volatil yang dominan masih berupa asam heksadekanoat (42.8 – 71.6%). Secara umum, karakteristik dan profil senyawa volatil fraksi 225, 250, dan 275°C memiliki kesamaan dan berbeda dengan fraksi 300oC., The synthesis of biofuels from vegetable oil using a pyrolysis reactor was studied as an alternative to the bio hydrocarbon process which has properties similar to fossil fuels. This research used palm cooking oil as raw material that reacted at a temperature gradually increased from 225, 250, 275, and 300°C, and used zeolite as a catalyst. The condensed volatile compounds were collected based on the fraction and analyzed for color, density, kinematic viscosity, moisture content, pour point, caloric value, and composition of volatile compounds based on GCMS analysis. Palm cooking oil as a raw material has a moisture content of 0.095% (w/w), kinematic viscosity of 41.25 mm2/s, a pour point of 20°C, and a calorific value of 39.93 MJ/Kg. The bio hydrocarbon fractions at various temperatures have a red to bright yellow color, and a liquid phase, and only the 300°C fraction has a solid fraction. The density of bio hydrocarbons ranges from 0.8452 - 0.8527 g/cm3 (40°C), kinematic viscosity 3.0726 - 3.8137 mm2/s, water content 0.0801 - 0.1878% (w/w) and point pour 4 - 22°C. The density, kinematic viscosity, and pour point of the temperature fraction 225 – 275°C meet the national standards for biodiesel and diesel. The composition of volatile compounds mainly consisted of n-decanoic acid, undecanoic acid, dodecanoic acid, 8-heptadecene, heptadecane, tetradecanoic acid, and n-hexadecanoic acid. The main content of volatile compounds was still in the form of fatty acids where n-hexadecanoic acid was the dominant compound (42.8 - 71.6%). In general, the characteristics and profiles of volatile compounds in the fractions 225, 250, and 275°C were similar and different from the 300oC fraction.
Keyword: bio hydrocarbon, fatty acid, palm cooking oil, pyrolysis

Judul: Karakteristik Anatomi Skelet Kepala Buaya senyulong (Tomistoma schlegelii).
Abstrak: Buaya sepit atau senyulong (Tomistoma schlegelii) merupakan jenis buaya asli Indonesia yang berhabitat di sungai-sungai Sumatera, Kalimantan, dan juga pedalaman Sulawesi. Salah satu ciri khas buaya senyulong adalah bentuk moncong yang runcing dan sempit, namun hingga saat ini informasi mengenai struktur skelet kepala buaya senyulong sangat terbatas. Penelitian ini bertujuan untuk mempelajari karakteristik anatomi skelet kepala buaya senyulong yang dikatikan dengan fungsi dan perilakunya. Penelitian dilakukan secara eksploratif dengan melakukan pengamatan, pencatatan, dan pengambilan gambar dari skelet kepala buaya senyulong. Skelet kepala berukuran panjang 70 cm, lebar 29 cm, dan tingggi 17 cm dengan permukaan kasar pada os nasale, os frontale, os maxilla, os mandibula, os lacrimale, os jugale. Jumlah gigi pada buaya ini sebanyak 78 buah, terdiri dari 4 buah gigi premaxila, 16 buah gigi maxila, dan 19 buah gigi mandibula. Pada regio orbitalis ditemukan dua pasang fenestrae temporales yang berkembang baik. Fenestra supratemporale merupakan lubang oval yang membentang di sepanjang os parietale. Fenestra infratemporale berbentuk segitiga dan dibatasi oleh os squamosum, os postorbitale, os jugulare, dan os quadratum. Os mandibula hewan ini mempunyai symphysis mandibularis yang panjang yaitu garis yang melintang di corpus mandibulae. Secara fungsional ukuran symphysis mandibularis berkaitan dengan adaptasi hewan terhadap diet makan.
Keyword: kepala, moncong, Tomistoma schlegelii