Judul: Pemanfaatan Kulit Buah Kola Sebagai Katalis Heterogen Untuk Produksi Biodiesel Dari Minyak Goreng Curah
Abstrak: Energi merupakan kebutuhan yang tidak dapat dipisahkan dari kehidupan manusia. Sumber energi yang sering digunakan seperti minyak bumi, batu bara, dan gas memiliki cadangan yang terus berkurang berbanding terbalik dengan penggunaanya. Salah satu sumber energi terbarukan adalah biodiesel. Dalam prosesnya diperlukan katalis untuk mempercepat reaksi pembentukan biodiesel. Jenis katalis yang dapat digunakan adalah katalis heterogen. Katalis ini dapat berasal dari limbah pertanian seperti kulit buah kola. Katalis yang berasal dari kulit buah kola dibuat melalui proses kalsinasi pada berbagai suhu yaitu 550 °C, 625 °C, dan 700 °C selama 4 jam. Konsentrasi katalis yang digunakan pada pembuatan biodiesel yaitu 2%, 3%, dan 4%. Proses pembuatan biodiesel menggunakan suhu reaksi sebesar 60 °C dengan waktu reaksi transesterifikasi selama 2 jam. Hasil dari analisis katalis seperti Scanning Electron Microscope (SEM), X-Ray Diffraction (XRD), Atomic Absorption Spectroscopy (AAS), dan penggunaan ulang katalis. Biodiesel yang telah diproduksi juga dianalisis seperti rendemen, densitas, angka asam, bilangan penyabunan, gliserol total, dan kadar metil ester. Hasil terbaik diperoleh pada suhu kalsinasi terbaik yaitu 550 °C dengan konsentrasi katalis sebesar 3%. Rancangan percobaan yang digunakan pada penelitian ini yaitu rancangan acak lengkap faktorial dua faktor dan dianalisis dengan ANOVA (α = 0,05) serta uji lanjut Duncan. Penelitian ini dapat disimpulkan bahwa suhu kalsinasi dan konsentrasi biodiesel mempengaruhi hasil biodiesel., Energy is a necessity that cannot be separated from human life. Energy sources, such as petroleum, coal, and gas, have reserves that continuously decrease inversely with their usage. One of the renewable energy sources is biodiesel. In its production process, a catalyst is needed to speed up the biodiesel formation reaction. The type of catalyst that can be used is a heterogeneous catalyst. This catalyst can be derived from agricultural waste, such as kola nut pod husk. Catalysts derived from kola nut pod husk are produced through calcination processes at various temperatures, namely 550 °C, 625 °C, and 700 °C for 4 hours. The catalyst concentration in biodiesel production is 2%, 3%, and 4%. The biodiesel production process uses a reaction temperature of 60 °C with a transesterification reaction time of 2 hours. The results of catalyst analysis include Scanning Electron Microscope (SEM), X-Ray Diffraction (XRD), Atomic Absorption Spectroscopy (AAS), and catalyst reusability. The biodiesel is also analyzed for yield, density, acid number, saponification number, total glycerol, and methyl ester content. The best results are obtained at the optimum calcination temperature of 550 °C with a catalyst concentration of 3%. The experimental design used in this research is a two-factor full factorial design, and it is analyzed using ANOVA (α = 0.05) and the Duncan post hoc test. This study can be concluded that calcination temperature and biodiesel concentration affect biodiesel yield.
Keyword: biodiesel, calcination, kola pod husk, concentration, heterogeneous catalyst

Judul: The Utilization of Kemiri Sunan Fruit Peel as Catalyst in the Conversion Process of Crude Oil into Biodiesel
Abstrak: Pemanfaatan buah kemiri sunan sebagai bahan baku pembuatan biodiesel akan menghasilkan limbah berupa kulit buah. Bila tidak dikelola dengan baik, maka dapat mencemari lingkungan. Kandungan senyawa kalium yang terdapat pada kulit buah kemiri sunan berpotensi untuk dimanfaatkan sebagai katalis heterogen dalam proses transesterefikasi pembuatan biodiesel. Penelitian ini bertujuan mengetahui pengaruh waktu transesterifikasi dan konsentrasi katalis kulit kemiri sunan dalam pembuatan biodiesel. Katalis yang terdapat pada kulit buah kemiri sunan diaktivasi terlebih dahulu melalui proses kalsinasi dengan suhu 800 oC 4 jam. Proses pembuatan biodiesel dilakukan menggunakan hotplate dengan suhu 60 oC dengan perbandingan mol metanol 1:6 dengan waktu reaksi transesterifikasi selama 1 dan 2 jam dengan kecepatan pengadukan 500 rpm. Konsentrasi katalis yang digunakan yaitu 1,5%, 1,75%, 2% dan 2,25%. Rancangan percobaan yang digunakan pada penelitian ini yaitu rancangan acak lengkap faktorial dua faktor dan dianalisis dengan ANOVA (α=0,05). Parameter penentu kondisi terbaik adalah rendemen, viskositas, densitas, dan angka asam biodiesel. Hasil rendemen terbaik yang didapatkan sebesar 78,22% dalam waktu transesterifikasi 60 menit dengan konsentrasi katalis 1,5%. Dari hasil penelitian ini didapatkan hasil biodiesel yang sesuai SK Dirjen EBTKE No. 189/2019 dengan nilai rendemen sebesar 70,89% – 78,22%, nilai densitas sebesar 0,869 – 0,875 g/m3, nilai viskositas sebesar 3,07 – 3,22 cSt. Angka asam dengan nilai 0,44 – 0,78 tidak sesuai dengan standar dengan nilai maksimal 0,4., The utilization of Kemiri Sunan candlenut fruit as a feedstock for biodiesel production generates waste in the form of fruit peels. If not managed properly, this waste can pollute the environment. The presence of potassium compounds in sunan candlenut fruit peels has the potential to be utilized as a heterogeneous catalyst in the transesterification process of biodiesel production. This research aims to investigate the influence of transesterification time and the concentration of sunan candlenut fruit peel catalyst in biodiesel production. The catalyst in sunan candlenut fruit peels is first activated through a calcination process at a temperature of 800 °C for 4 hours. The biodiesel production process is carried out using a hotplate at a temperature of 60 °C with a methanol-to-oil mole ratio of 1:6, and transesterification reaction times of 1 and 2 hours, with a stirring speed of 500 rpm. The concentrations of catalyst used are 1.5%, 1.75%, 2%, and 2.25%. The experimental design used in this study is a two-factor completely randomized factorial design, and the data are analyzed using ANOVA (α=0.05). The key parameters for determining the optimal conditions are yield, viscosity, density, and acid value of the biodiesel. The best yield obtained is 78.22% at a transesterification time of 60 minutes with a 1.5% catalyst concentration. The results of this study yield biodiesel that complies with the Directorate General of New and Renewable Energy and Energy Conservation (DG EBTKE) Regulation No. 189/2019, with a yield ranging from 70.89% to 78.22%, density values ranging from 0.869 to 0.875 g/m3, and viscosity values ranging from 3.07 to 3.22 cSt. However, the acid value, with a range of 0.44 to 0.78, does not meet the standard, which has a maximum value of 0.4.
Keyword: biodiesel, kalsinasi, katalis heterogen, konsentrasi, calcination, concentration, heterogeneous catalyst

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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