Judul: Analysis of Kinetic Transesterification Reaction in Catalytic Biodiesel Production with Static Mixing Reactor
Abstrak: Catalytic process of biodiesel production requires rigorous mixing and a certain amount of catalyst itself in order to obtain the proper result of the process. Hipotetically, a good mixing can reduce the amount of required catalyst for a certain results. In this study, a static mixing reactor with KOH as catalyst was used to produce biodiesel. The objective of the study were (1) to evaluate the affect of decreassing the amount of KOH required as catalyst for the biodiesel production in the static mixing reactor (2) to study the kinetics of the reaction. The result showed that the percentage of catalyst greatly affected the reaction conversion, yield and kinetics of the transesterification reaction at the beginning of the reaction and declined afterward, because its ability nearly reached its maximum capacity. The model of reaction order that most appropriate to describe the condition of transesterification in this study was a pseudo third-order model. The activation energy was 71.83 kJ mol-1, and the influence of static mixers in the reactor was indicated by the value of the collision frequency factor (1.95 x 108 min-1). In other words, the presence of static mixer has a significant influence in accelerating the reaction.
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Judul: Analisis Metode Response Surface pada Produksi Biodiesel secara Katalitik dengan Static Mixing Reactor
Abstrak: Transesterification process of palm olein with static mixing reactor is influenced by temperature, time and percentage of KOH catalyst. This study aims to determine optimum operating condition of a static mixing reactor for biodiesel production in batch system using Response Surface Methodology ( RSM ) box - Behnken. Catalytic biodiesel production process was carried out using a static mixing reactor, where palm olein, methanol, and catalyst were flown to the static mixer with reaction temperature of 30oC, 45oC, 60oC . Catalyst concentration given in this study were 0.3 % , 0.4 %, 0.5 %, while time for sampling was 20, 30, and 40 minutes. Laboratory analysis was conducted to obtained acid number, saponification number and total glycerol numbers, and by calculation that methyl esters content was 97.41 % w / w. This figure has met the SNI standard of methyl ester content which is 96.5%. Optimum operating condition was found at temperature of 300C, operating time is 45 minutes and 0.4 % of KOH catalyst.
Keyword: response surface, methyl esther, biodiesel

Judul: Habitat dan biologi burung walet sarang hitam (Collocalia maximaa) di Gua Way Nenok, Taman Nasional Bukit Barisan Selatan
Abstrak: Sarang burung walet dimanfaatkan sebagai makanan orang sejak pertengahan abad 14, yang pengambilannya banyak dilakukan di gua-gua alam. Sarang burung walet sarang putih (Collocalia fuciphaga) dan walet sarang hitam (Collocalia maxima) merupakan barang bernilai ekonomis yang telah diperdagangkan di dunia internasional, komoditi sarang burung dikenal dengan nama "bird's nest". Di Indonesia penelitian ilmiah mengenai walet sarang hitam belum banyak dilakukan. Penelitian dilaksanakan di Gua Way Nenok yang terletak di Taman Nasional Bukit Barisan Selatan. Waktu penelitian pada bulan Oktober-Nopember 1.997. Penelitian ini bertujuan untuk mengumpulkan informasi dan pengetahuan mengenai kondisi habitat dan biologi walet sarang hitam (Collocalia maxima), khususnya kondisi fisik gua, perilaku, dan morfologi. Hasil dari penelitian diharapkan dapat memberikan masukan dalam pengelolaan gua sebagai penghasil sarang burung walet berdasarkan asas kelestarian hasil sarang dan kelestarian populasi burung walet. Burung walet sarang hitam secara keseluruhan berwarna coklat kehitaman, bulu pada bagian bawah tubuh berwarna coklat. Garis-garis putih terdapat pada lingkaran leher, dada, tungging dan pangkal ekor bagian bawah. Alis mata tebal menyerupai elang, ekor hampir tidak bercelah dan...
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