Judul: The Effect of Adding Iron Oxide (Fe2O3) in Zeolite Synthesis of Natural Kaolin
Abstrak: Penambahan reaktan tambahan pada proses sintesis zeolit akan menghasilkan zeolit tertentu, sehingga penambahan variasi konsentrasi oksida besi (Fe2O3) pada sintesis zeolit dari kaolin Bangka Belitung akan berpengaruh terhadap struktur kristal dari zeolit yang diperoleh. Tujuan penelitian ini adalah mengidentifikasi pengaruh penambahan berbagai konsentrasi Fe2O3 terhadap tipe struktur kristal dari zeolit yang terbentuk. Komposisi perbandingan Fe2O3 yang ditambahkan, yaitu 5%, 10%, dan 15%. Proses sintesis dilakukan dengan metode hidrotermal pada suhu 100 °C selama 24 jam dengan konsentrasi NaOH 0.75 N dan 1.5 N. Hasil sintesis dicirikan dengan difraksi sinar-X, mikroskop pemindai elektron, dan dilakukan pengujian kapasitas tukar kation (KTK). Hasil difraktogram menunjukkan, penambahan variasi konsentrasi Fe2O3 tidak berpengaruh terhadap pembentukan tipe struktur kristal, akan tetapi berpengaruh terhadap kristalinitasnya. Dari penggunaan NaOH 1.50 N dan 0.75 N semuanya menunjukkan puncak-puncak standar zeolit A. Nilai KTK mengalami penurunan seiring dengan bertambahnya konsentrasi Fe2O3.
Keyword: Bogor Agricultural University, Institut Pertanian Bogor, IPB, Fe2O3, Kapasitas tukar kation, Metakaolin, Zeolit, Metakaolin, Difaktogram kaolin, Hasil SEM

Judul: Modifikasi zeolit melalui interaksi dengan Fe(OH)3 untuk meningkatkan kapasitas tukar anion
Abstrak: Zeolite structure, that bears negative charge caused by replacement of Si with Al in the process of its formation, makes the zeolite has a function as cation exchanger and some anion exchange. To improve its anion exchange properties, zeolite can be modified by addition of Fe(OH)3. Fe3+ ions will enter empty cavities of the zeolite and bind the anions (ligands) to form complexes. Based on the esperiment, the modified zeolite with Fe(OH)3 can be made from both natural and active zeolites, increasing the anion exchange capacity of the zeolite. The anion exchange capacity of the modified zeolite was higher that of the zeolite before modification,i.e. 5.064 and 17.449 meq/100 g, respectively. Modification of zeolite with Fe(OH)3 inhibited adsorption of methylene blue, due to structural changes in the nature of the zeolite after modification. Zeolite adsorption capacity from methylene blue were the largest on the unmodified active zeolite, which was 0.7199 mg/g.
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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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