Judul: Surfaktan Berbasis Minyak Sawit untuk Aplikasi Enhanced Oil Recovery (EOR) pada Lapangan Minyak Intermediet
Abstrak: Penurunan produksi minyak bumi terus terjadi dari tahun ke tahun. Penemuan cadangan minyak baru bukan merupakan hal mudah. Disisi lain, Indonesia mempunyai banyak lapangan minyak tua dengan sisa minyak yang masih relatif tinggi. Untuk itu, peningkatan produksi minyak tahap lanjut (EOR) perlu dilakukan. Injeksi kimia, khususnya surfaktan sebagai bagian dari aplikasi EOR sudah terbukti mampu meningkatkan perolehan minyak dari lapangan minyak tua. Namun demikian, ketersediaan surfaktan untuk aplikasi EOR masih sangat terbatas. Diperlukan banyak penelitian untuk menghasilkan formula surfaktan yang sesuai untuk lapangan-lapangan minyak tua di Indonesia yang jumlahnya sangat banyak. Beberapa surfaktan berbasis minyak sawit disintesa, yaitu surfaktan Metil Ester Sulfonat (MES), Butil Ester Sulfonat (BES) dan Polietilen Dioleat Sulfonat (PDS). Ada tiga varian surfaktan PDS yaitu PDSH1, PDSH2 dan PDSH3. Proses sintesa surfaktan terdiri dari beberapa tahapan, yaitu reaksi sulfonasi, pemutihan, netralisasi dan evaporasi. Perbedaan 3 jenis surfaktan PDS adalah pada lamanya waktu proses sulfonasi dilakukan, yaitu 120 menit, 90 menit dan 60 menit. Parameter uji screening seperti kompatibilitas, tegangan antarmuka (IFT), filtrasi, dan thermal stability dilakukan sebelum diaplikasikan pada lapangan minyak intermediet. Formulasi juga dilakukan untuk mengoptimalkan kinerja surfaktan. Dari kelima varian surfaktan dan serangkaian hasil formulasi didapatkan formula terbaik 1% surfaktan PDSH3 yang memenuhi kriteria pada uji screening. Karakterisasi FTIR dan analisa gravimetri thermal dilakukan untuk menentukan gugus fungsi sulfonat dan mengukur degradasi perubahan massa surfaktan terhadap panas. Uji injeksi kimia skala laboratorium dilakukan dengan batuan standar dan menghasilkan peningkatan perolehan minyak sekitar 20%. Formula surfaktan yang dihasilkan dari penelitian ini diharapkan dapat diaplikasikan sehingga mampu meningkatkan perolehan minyak dari lapangan minyak tua. Untuk lebih mengoptimalkan kinerja surfaktan, formulasi lebih lanjut perlu dilakukan. Selain itu, perlu dilakukan variasi desain injeksi surfaktan.
Keyword: surfaktan, tegangan antarmuka, formulasi, perolehan minyak, uji screening

Judul: Kajian kinerja Surfaktan Mes (Metil Ester Sulfonat) dari Jarak Pagar (Jatropha Curcas L.) untuk enhanced waterflooding
Abstrak: Year by year, the production of petroleum decreases but its demand increases. The world will get the energy crisis if that condition happens continously. The main cause of low production of petroleum in Indonesia is the majority Indonesia’s oil wells being mature field/brown field and the discovery of new oil field in small scale. Indonesia focuses on maximize oil recovery in brown field because its oil production decreases naturally up 15% in total production. In recent years, the field of enhanced oil recovery has grown became more popular due to a combination of stagnant oil production and low recoveries by conventional methods. Many fields use unconventional method like enhanced oil recovery (EOR) which is tertiary oil recovery phase. One way of EOR is chemical flooding which uses surfactant for injection. Surfactant is injected to water and it is known as enhanced waterflooding. Generally, surfactant of petroleum sulfonates is used for oil recovery. This surfactant has many weaknesses such as resistance to water hardness, susceptible detergency to high salinity and being imported with expensive price. Due to these weaknesses, therefore it trigger to get surfactant substitute like MES (methyl ester sulfonates) that is synthesized by biooil. One of biooil is Jatropha oil. The study was aimed to know experimental of surfactant formula for enhanced waterflooding in fluida sample of oil field and synthetic core sandstone. The result showed that injection of surfactant 0,2 PV gave the influence differently to oil recovery. The best condition was surfactant 0,2 PV with the soaking time of 12 hours. This formula gave the highest of incremental total oil recovery 61,07%. The number were resulted from 47,73% waterflooding and 13,34% surfactant injection. Surfactant formula gave the good performance of compatibility, thermal stability, phase behavior and filtration test.
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Judul: Categorization in Macaca fascicularis.
Abstrak: Categorization is an ability to group individuals or events into different classes mediated by conceptualized mental images. There are several levels of categorization and within a taxonomy the levels are nested. At the most concrete level of categorization, all or most members of the category shared common physical attributes that differ from other categories. The higher the level of category, the fewer common attributes between members of the group. In addition to humans, the ability to categorize has also been proposed in animals. One example of categorization in animal is species discrimination. Using matching-tosample task, present experiment tested ability of the long-tailed macaque (Macaca fascicularis) in discriminating dichotomous-stimuli of different animals. The species has been shown to be able to see photos as representations of real object so I used facial photos of humans and animals for the stimuli. First, I tested their ability to classify humans and macaques into separate group. Second, I tested their ability to discriminate their conspecific from other macaques. And the last, I tested whether the subjects were able to discriminate non-human animals from humans. In all of these experiments I found that the subjects showed high performance in categorizing objects, even when I discarded details of visual informations, such as color and local shapes. The ability to identify objects with reduced representation of physical properties means the subjects were able to generalize attributes of members of the group. This would indicate that the subjects created a higher level abstraction. On the other hand, in discriminating intrageneric macaque species I found that they were able to extract uniqueness of each species. More over, I also found that the subjects were able to put photos of non-human animals that shared very few similarities in physical percepts into one group. I suggested that the subjects could create a more abstract concept based on non-percepts relations as a basis to put the objects into one category. Thus, I concluded that M. fascicularis were able to perform multiple levels of categorizations.
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