Judul: Biodiesel Production from Used Cooking Oil Using KOH Catalyst by Ultrasonic Wave Method
Abstrak: Kebijakan penggantian BBM menjadi bahan bakar nabati telah dikeluarkan untuk mengurangi tekanan impor dan ancaman ketahanan energi, salah satunya melalui pembuatan biodiesel dari minyak jelantah. Teknologi pembuatan biodiesel secara konvensional membutuhkan waktu yang lama serta energi yang cukup besar. Metode ultrasonik dapat menjadi alternatif karena dapat mempersingkat waktu serta membutuhkan input energi yang lebih kecil. Penelitian ini bertujuan melihat pengaruh waktu paparan gelombang ultrasonik (5, 10, dan 15 menit) dan konsentrasi katalis KOH (1,0%, 1,5%, dan 2,0% b/b) dan membandingkannya dengan nilai SNI. Mutu yang diuji dan dianalisis pada hasil biodiesel yaitu yield, viskositas kinematik, densitas, dan bilangan asam. Rancangan percobaan pada penelitian menggunakan rancangan acak lengkap dengan dua faktor, dan dianalisis dengan ANOVA (α = 0,05) dan uji lanjut Duncan. Hasil perlakuan terbaik yang diperoleh yaitu perlakuan konsentrasi katalis KOH 2,0% dengan waktu transesterifikasi selama 15 menit. Perlakuan tersebut menghasilkan yield sebesar 78,61%, viskositas kinematik sebesar 4,505 cSt, densitas sebesar 850,2761 kg/m3, dan bilangan asam sebesar 0,468 mg KOH/g. Seluruh mutu pada perlakuan ini telah memenuhi standar SNI 7182:2015., The policy of subtituting fossil fuel into biofuels has been issued to reduce import pressure and the threat of energy security, one of which is by making biodiesel from used cooking oil. Conventional biodiesel production technology requires a long time and considerable energy. The ultrasonic method can be an alternative because it can shorten the time and requires less input energy. This research aims to analyze the effect of exposure time to ultrasonic waves (5, 10, and 15 minutes) and KOH catalyst concentration (1,0%, 1,5%, and 2,0% w/w) and compare them with the SNI. The parameters tested and analyzed on the biodiesel were yield, kinematic viscosity, density, and acid number. The experimental design in this research used a complete randomized design with two factors, and was analyzed by ANOVA (α = 0,05) and Duncan's post hoc test. The best treatment result obtained is the treatment of 2,0% KOH catalyst concentration with a transesterification time of 15 minutes. The treatment resulted a yield 78,61%, kinematic viscosity 4,505 cSt, density 850,2761 kg/m3 and the acid value 0,468 mg KOH/g. All quality in this treatment has met the SNI 7182:2015.
Keyword: biodiesel, transesterification, ultrasonic, used cooking oil

Judul: Comparative Study of the Using the Homogeneous NaOH Catalyst with the Heterogeneous Catalyst Based on CaO to Yield of Biodiesel from Used Cooking Oil
Abstrak: Produksi biodiesel melalui proses transesterifikasi dapat dilakukan melalui proses katalitik maupun non-katalitik. Metode transesterifikasi katalitik dapat dibagi menjadi dua yaitu dengan menggunakan katalis homogen dan katalis heterogen. Penelitian ini bertujuan membandingkan pengaruh penggunaan katalis homogen NaOH dan heterogen berbasis CaO, mengetahui kondisi terbaik masingmasing katalis, serta menganalisis keekonomian dari penggunaan katalis homogen NaOH dan heterogen berbasis CaO terhadap hasil biodiesel dari minyak jelantah. Penelitian ini mengunakan metode studi literatur. Berdasarkan analisis pembobotan didapatkan variasi variabel terbaik dari penggunaan katalis homogen NaOH yaitu pada rasio molar minyak dan metanol 1:2, jumlah katalis 0,5%, reaksi pada suhu 50-60 oC selama 1 jam menghasilkan yield biodiesel sebanyak 99,59 %. Sedangkan pada penggunaan katalis heterogen berbasis CaO adalah dengan jenis katalis CaO komersil+SrO. Perbandingan rasio molar minyak/metanol 1:3, jumlah katalis 4 % dengan menggunakan metode batch dengan bantuan microwave daya 100 watt selama 0,0333 jam, menghasikan yield biodiesel 92,86 %. Harga pokok produksi untuk memproduksi biodiesel 100 liter per hari diperoleh pada penggunaan perlakuan terbaik katalis NaOH sebesar Rp. 5296,57/liter. Sedangkan pada katalis berbasis CaO diperoleh sebesar Rp. 5960,76 /liter., Catalytical or non-catalytical techniques can be used to produce biodiesel during the transesterification process. The method of catalytic transesterification can be split into two types: homogeneous and heterogeneous catalysts. The purpose of this research is first, to compare the effects of homogeneous catalyst of NaOH and heterogeneous catalysts based on CaO to biodiesel yields from used cooking oil; second, to determine the best conditions for each catalyst, and third, to analyze the economics of using both catalysts. This research uses the literature study method. Base on the scoring analysis, the research obtained that the best variation of variables of homogenous NaOH catalyst was at a parameter of 1:2 molar ratio of oil and methanol. The amount of catalyst was 0.53%, and the reaction at a temperature of 50-60 oC for 1 hour produced biodiesel yield of 99.59%. While the using of heterogeneous catalysts base on CaO was the type of commercial CaO + SrO catalyst. The molar ratio of oil to methanol was 1:3, the amount of catalyst was 4% using the batch method with the help of a microwave power of 100 watts during 0.0333 hours produced 92.86% biodiesel yield. The cost of biodiesel production for 100 liters/day which obtained at the best treatment of NaOH catalyst was Rp. 5296.57/liter and the use of CaO-based catalyst was Rp. 5960.76/liter.
Keyword: Biodiesel, CaO, Catalyst, NaOH, Used Cooking Oil.

Judul: Posisi Filogenetik Kura-Kura Carettochelys Insculpta  (Reptillia: Testudinata)
Abstrak: Carettochelys insculpta is an endemic freshwater turtle of southern Papua and northern Australia. Phylogenetic position of this turtle is remain unresolved until now. Most of the research conducted show close relationships of C. insculpta and members of Trionychidae family. However, some of the research show distance between C. insculpta and members of Trionychidae family. This research is conducted to analyze phylogenetic relationship between C. insculpta and other members of Testudinata using 12S rRNA, 16S rRNA, and both gene as markers. DNA samples were obtained from three different organisms of C. insculpta. Two species used as outgroups were Alligator mississippiensis and Iguana iguana. Phylogenetic analysis was carried out using Neighbor-Joining method with Felsenstein 1981 (F81) modeltest. A polytomy tree of Testudinata was produced by using 12S rRNA gene. However, analysis using 16S rRNA and both genes as markers confirmed that C. insculpta was located between the Chelonidae and the Trionychidae family.
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