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All Journal Reaktor Journal of Engineering and Technological Sciences JURNAL SELULOSA ASEAN Journal of Chemical Engineering Jurnal Teknologi Bahan dan Barang Teknik Jurnal Teknik Kimia Indonesia Bulletin of Chemical Reaction Engineering & Catalysis

S. Subagjo

Chemical Engineering Department, Institut Teknologi Bandung

Author-ID : 444851

Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Computer Science & IT Control & Systems Engineering Education Electrical & Electronics Engineering Energy Engineering Materials Science & Nanotechnology

Published : 31 Documents Claim Missing Document

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POTENSI KATALIS PADAT ASAM GAMMA ALUMINA TERSULFATASI PADA REAKSI ESTERIFIKASI MINYAK BIJI KARET Maria Ulfah; S Subagjo
Reaktor Volume 16 No.3 September 2016
Publisher : Dept. of Chemical Engineering, Diponegoro University

POTENTIAL OF SULFATET ALUMINA-HETEROGENEOUS ACID CATALYST IN ESTERIFICATION RUBBER SEED OIL. Two tipe of catalysts have been synthesed and evaluated ( free fatty acid conversion) in esterification of rubber seed oil. The first and the second catalyst have content SO3 8,821 % and 40,715 %, respectly. The optimum condition of reaction studied : volume ratio methanol/oil 0,9-1,8 v/v; catalyst concentration 1,67-10 % wt/v; time of reaction 1-7 hours and temperature of reaction 50-70 oC. This study showed, the second catalyst more active than the first catalyst. Maximum conversion from esterification reaction of rubber seed oil of the first and the second catalyst are 75 % and 97 %, respectly. The optimum condition of reaction achieved at volume ratio methanol/oil 1,8 v/v; catalyst concentration 1,67 % wt/v; time of reaction 7 hours and temperature of reaction 70 oC. Keywords: sulfated alumina, free fatty acid, eterification, rubber seed oil.AbstrakDua tipe katalis alumina tersulfatasi telah disintesis dan dievaluasi kinerjanya (berupa konversi Asam Lemak Bebas, ALB) pada reaksi esterifikasi asam lemak bebas minyak biji karet. Katalis tipe 1 dan tipe 2 berturut-turut memiliki kandungan SO3 8,821 % dan 40,715 %. Kondisi optimasi reaksi yang dipelajari: rasio volume metanol/minyak 0,9-1,8 v/v; konsentrasi katalis 1,67-10 % b/v; waktu reaksi 1-7 jam dan temperatur reaksi 50-70 oC. Hasil penelitian menunjukkan katalis tipe 2 lebih aktif dari tipe 1. Konversi ALB maksimum dari reaksi esterifikasi minyak biji karet dengan katalis tipe 1 dan tipe 2 berturut-turut 75 % dan 97 %. Kondisi optimum reaksi tersebut dicapai pada rasio volume metanol/minyak 1,8; konsentrasi katalis/minyak 1,67 % b/v; lama reaksi 7 jam dan temperatur reaksi 70 oC. Kata kunci: alumina tersulfatasi, asam lemak bebas, esterifikasi, minyak biji karet

KINETIKA HIDRODESULFURISASI DIBENZOTHIOPHENE (HDS DBT) MENGGUNAKAN KATALIS NiMo/γ-Al2O3 Subagjo Subagjo; Maria Ulfah
Reaktor Volume 14, No. 4, OKTOBER 2013
Publisher : Dept. of Chemical Engineering, Diponegoro University

Evaluasi kinetika reaksi hidrodesulfurisasi (HDS) dibenzothiophene dan simulasi nafta hydrotreater yang berada di PT. PERTAMINA Refinery Unit II Dumai menggunakan katalis NiMo/Al2O3 hasil pengembangan telah dilakukan. Kinetika reaksi HDS DBT dilakukan dalan sistem reaktor batch dengan variasi temperatur 280-320oC dan tekanan 30 bar. Data kinetika diolah dengan persamaan hukum pangkat (law power) dan persamaan kinetik mekanistik (Langmuir Hinshelwood, LH). Berdasarkan model hukum pangkat, kinetika HDS DBT menggunakan NiMo/Al2O3 hasil pengembangan merupakan orde satu terhadap DBT dengan konstanta Arhenius sebesar 165633 detik-1 dan energi aktivasi 69017 J/mol (16,56 kkal/mol). Model LH yang cocok untuk reaksi HDS DBT menggunakan NiMo/Al2O3 hasil pengembangan adalah model LH yang mengilustrasikan adanya kompetisi antara reaktan DBT dan H2 pada tipe pusat aktif yang sama, dengan DBT teradsorb secara kuat sedangkan H2 teradsorpsi secara lemah. Energi aktifasi dan konstanta Arhenius berdasarkan model LH ini ini berturut-turut adalah 81409 J/mol (19,34 kkal/mol) dan 1658133 s-1. Dengan menggunakan persamaan laju reaksi hukum pangkat, model memberikan hasil konversi sulfur yang sama dengan hasil keluaran reaktor nafta hydrotreater RU II-Dumai, yaitu mencapai 98%.

PENGARUH PERBEDAAN SIFAT PENYANGGA ALUMINA TERHADAP SIFAT KATALIS HYDROTREATING BERBASIS NIKEL-MOLIBDENUM Maria Ulfah; Subagjo Subagjo
Reaktor Volume 14, Nomor 2, Oktober 2012
Publisher : Dept. of Chemical Engineering, Diponegoro University

EFFECT OF ALUMINA SUPPORT PROPERTIES ON THE NICKEL-MOLIBDENUM BASE HYDROTREATING CATALYST. Effect of surface characteristics of three species of synthesized γ-alumina (alumina-1, alumina-2 and alumina-3) on characteristics NiMo catalysts has been studied. Those aluminas are derived from boehmite Catapal B by varying rasio mol nitric acid to boehmite. A sol-gel method is used to synthesize γ-Al2O3 support. The Nitrogen adsorption, X-ray diffraction (XRD), Temperature Programmed Reduction (TPR) of H2, Temperature Programmed Desorption (TPD) of NH3, and mechanical strength are used to characterize the supports and catalysts. The results showed that the surface area alumina affects the formation of crystalline MoO3 in the NiMo catalyst, while γ-Al2O3-3 support which has the highest surface area (about 195 m2/g) compared to the other two types of alumina (>195 m2/g) does not have a crystalline MoO3. The formation of crystalline MoO3 is not influenced by the acidity alumina. Based on the results of XRD, it is indicated that the supported alumina-3 NiMo catalyst (having the highest acid strength) shows that there is no presence of crystalline MoO3. Pore size distribution of support did not change significantly after the deposition of Ni and Mo oxides. Mechanical strength of support also affects the strength NiMo catalyst. Support alumina-3 which has the highest mechanical strength gives the mechanical strength of the highest NiMo catalyst. Pengaruh sifat penyangga γ-alumina hasil pengembangan (alumina-1, alumina-2 dan alumina-3) pada karakter katalis hydrotreating nikel-molibdenum (NiMo) telah dipelajari. Ketiga jenis γ-alumina diturunkan dari boehmite “Catapal B” dengan menvariasikan nisbah mol asam nitrat terhadap boehmite. Pembuatan γ-alumina menggunakan metoda sol-gel. Adsorpsi Nitrogen, X-ray difraksi (XRD), Temperature Programmed Reduction (TPR) H2, Temperature Programmed Desorption (TPD) NH3, dan kekuatan mekanik digunakan untuk mengkarakterisasi penyangga dan katalis. Hasil penelitian menunjukan bahwa luas permukaan alumina mempengaruhi pembentukan kristalin MoO3 dalam katalis NiMo. Pada penyangga alumina-3 yang memiliki luas permukaan yang paling tinggi (sekitar 195 m2/g) di banding dua jenis alumina lainnya (>195 m2/g) tidak memiliki kristalin MoO3. Pembentukan kristalin MoO3 tidak dipengaruhi oleh sifat keasaman alumina. Berdasarkan hasil XRD ditunjukan bahwa pada katalis NiMo berpenyangga alumina-3 (memiliki kekuatan asam yang paling tinggi) tidak terdapat adanya kristalin MoO3. Distribusi ukuran pori peyangga tidak berubah signifikan setelah deposisi oksida Ni dan Mo. Kekuatan mekanik penyangga mempengaruhi pula kekuatan katalis NiMo. Penyangga γ Al2O3-3 yang memiliki kekuatan mekanik yang paling tinggi memberikan kekuatan mekanik katalis NiMo yang tertinggi.

Production of Biogasoline via Pyrolysis of Oleic Acid Basic Soaps Endar Puspawiningtiyas; Tirto Prakoso; Meiti Pratiwi; Subagjo Subagjo; Tatang Hernas Soerawidjaja
Journal of Engineering and Technological Sciences Vol. 54 No. 3 (2022)
Publisher : Directorate for Research and Community Services, Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.eng.technol.sci.2022.54.3.11

In this study, an investigation on the effect of the Ca/Mg/Zn mixing ratio on gasoline-range hydrocarbon production by oleic basic soap pyrolysis was carried out. The ratios of calcium to magnesium used were 15%, 35%, 50%, 65%, and 85% with constant Zn. Oleic basic soap was obtained by saponification with the modified fusion method. Pyrolysis experiments were carried out at 450 °C using a semi-continuous reactor with a feed flow rate of 5 g/15 min. The process produced three fractions, i.e., gas, solid, and liquid (bio-hydrocarbon + water). The gas products were characterized by GC-TCD, and the results showed the presence of carbon dioxide, hydrogen, nitrogen, oxygen, and methane. Based on the GC-FID and FT-IR results, the bio-hydrocarbon comprised mainly homologous hydrocarbon from carbon number C7 to C19 containing n-alkanes, alkenes, various iso-alkanes, and some oxygenated compounds. All calcium ratios in the oleic basic soap produced hydrocarbon in the range of gasoline (C7-C11) as the dominant product. The maximum yield of gasoline (74.86%) was achieved at 15% calcium.

Metode operasi reverse flow reactor dengan umpan fluktuatif dalam pengolahan emisi gas metana di stasiun kompresor M. Effendy; Yogi Wibisono Budhi; Yazid Bindar; S Subagjo
Jurnal Teknik Kimia Indonesia Vol 8, No 3 (2009)
Publisher : ASOSIASI PENDIDIKAN TINGGI TEKNIK KIMIA INDONESIA (APTEKIM)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/jtki.2009.8.3.1

Operation method of reverse flow reactor with fluctuating feed for methane gas emmision processing in compressor station.The leak of CH4 from the compressor stations can not be avoided and it may cause the global warming. The impact of the global warming can be reduced by oxidizing CH4 into CO2. The CH4 capture strategy using the exhaust mounted on the top of the building causes (1) CH4 levels detected in the gas mixture is very small (±1% volume), (2) the feed gas temperature is near the ambient temperature (±30 oC), (3) the CH4 concentration fluctuates over time. The reverse flow reactor (RFR) is a fixed bed reactor, which has the ability to abate the leak of CH4 and has the ability to act as an autothermal reactor. The purpose of this research is to find a proper operation procedure of the fixed bed reactor for the oxidation of lean methane emission via modeling and simulation. The reactor model is based on the continuity equation and the heat balance, while the concentration of the feed gas behavior dynamic and modeled as a step function. The model was solved numerically using the software package FlexPDE version 6. At ST (switching time) 50 seconds, the RFR operates autothermally with heat accumulation in the inert section fluctuating between 12.4 to 14.2 kJ. At ST 100 seconds, the heat trap inside the reactor increases monotonically. The use of ST 100 seconds requires an additional operation procedure to keep the reactor safe.Keywords: Global warming, concentration dynamic, autothermal operation, modeling and simulation, reverse flow reactor. AbstrakKebocoran gas CH4 dari stasiun kompresor tidak dapat dihindarkan dan ini merupakan salah satu sumber penyebab pemanasan global. Dampak pemanasan global ini dapat dikurangi dengan mengoksidasi gas CH4 menjadi gas CO2. Strategi penangkapan gas CH4 menggunakan exhaust yang terpasang pada bagian atas gedung menyebabkan (1) kadar CH4 yang terdeteksi dalam campuran gas cukup kecil (±1% volume), (2) temperatur gas umpan mendekati temperatur ruangan (± 30 oC), (3) konsentrasi gas CH4 akan berperilaku dinamik. Reverse flow reactor (RFR) mempunyai kemampuan untuk mengatasi akibat yang ditimbulkan oleh proses penangkapan gas CH4 di stasiun kompresor dan mempunyai kemampuan secara ototermal. Tujuan penelitian ini adalah mendapatkan metode operasi yang tepat untuk mengatasi gas umpan yang berperilaku dinamik. Model yang dikembangkan mengacu pada persamaan kontinuitas dan konsentrasi gas umpan yang berperilaku dinamik dimodelkan sebagai fungsi step. Model diselesaikan menggunakan software FlexPDE versi 6. Penggunaan switching time (ST) yang tepat dapat mengatasi permasalahan konsentrasi gas umpan yang berperilaku dinamik. Pada ST 50 detik, RFR mampu bekerja secara ototermal dengan nilai akumulasi panas di bagian inert yang berfluktuasi antara 12,4–14,2 kJ. Pada ST 100 detik, panas yang terjebak di dalam reaktor semakin lama semakin meningkat. Penggunaan ST 100 detik memerlukan prosedur operasi tambahan untuk menjaga reaktor agar tidak meleleh dan menjaga reaktor tetap beroperasi secara ototermal. Kata Kunci: Pemanasan global, dinamika konsentrasi, operasi ototermal, pemodelan dan simulasi, reaktor aliran bolak-balik.

Non-Isothermal Pyrolysis Kinetic Studies of Kraft Pulp Mill Sludge and Its Blending with Coal Powder Syamsudin Syamsudin; Tobias Richards; Herri Susanto; Subagjo Subagjo
JURNAL SELULOSA Vol 9, No 01 (2019): JURNAL SELULOSA
Publisher : Center for Pulp and Paper

Non-isothermal pyrolysis of kraft pulp mill sludge and coal has been investigated. Blending sludge with coal resulted time increase to complete the pyrolysis. This phenomenon indicated that volatile matter in coal was more difficult to be degraded. Sludge pyrolysis at 10, 15, and 20°C/min remained residual mass fraction of 64.6% w/w, 62.4% w/w, and 64.4% w/w, respectively. Coal addition into sludge had reduced char yield. Char yield decreasing was due to lower content of coal ash compared to sludge ash. Sludge lost most of its mass at 200C-500°C, reached its peak at 280°C, and became slower at >500°C. Wide range of coal degradation temperature indicated that coal may contain components having a wide range temperature degradation, such as lignin. Based on the curve of mass loss rate of reaction, there were three peaks which indicates three reaction mechanisms of sludge-coal pyrolysis. All peaks followed the mechanism of first order reaction. First peak was likely to occur due to decomposition of hemicellulose and other highly volatile components. Second and third were associate with cellulose and lignin, respectively. The high thermal stability properties lead to a slow degradation of lignin, and its mass loss occurred in the a very wide of temperature range (160-900°C). Studi Kinetika Pirolisis Non-Isotermal Lumpur Industri Pulp Kraft dan Campurannya dengan Serbuk BatubaraPirolisis non-isotermal lumpur industri pulp kraft dan campurannya dengan serbuk batubara telah diselidiki. Pencampuran lumpur dengan batubara menghasilkan peningkatan waktu untuk menyelesaikan pirolisis. Fenomena ini menunjukkan bahwa zat volatil dalam batubara lebih sulit terdegradasi. Pirolisis lumpur pada 10, 15, dan 20°C/menit menghasilkan fraksi massa residu masing-masing 64,6% b/b, 62,4% b/b, dan 64,4% b/b. Penambahan batubara ke dalam lumpur mengurangi hasil arang. Penurunan hasil arang disebabkan oleh kandungan abu batubara yang lebih rendah dibandingkan dengan abu lumpur. Lumpur kehilangan sebagian besar massanya antara 200°C dan 500°C, dan mencapai puncaknya pada 280°C. Kehilangan massa melambat pada suhu >500°C. Rentang suhu yang lebar pada degradasi batubara menunjukkan bahwa batubara mengandung komponen yang memiliki suhu degradasi luas, seperti lignin. Berdasarkan kurva laju kehilangan massa, terdapat tiga puncak reaksi yang menunjukkan tiga mekanisme reaksi pirolisis lumpur-batubara. Semua puncak tersebut mengikuti mekanisme reaksi orde pertama. Puncak pertama kemungkinan terjadi karena dekomposisi hemiselulosa, dan komponen-komponen lain yang sangat mudah menguap. Puncak kedua dan ketiga masing-masing berhubungan dengan selulosa dan lignin. Sifat stabilitas termal yang tinggi menyebabkan degradasi lignin yang lambat, dan kehilangan massa terjadi dalam kisaran suhu yang sangat luas (160-900°C).

Effects Of Cu On The Modified Co-Based Catalyst Activity For Fischer-Tropsch Synthesis Zaky Al Fatony; Ahlul Hafizan Resha; Galang Putra Persada; IGBN Makertihartha; Melia Laniwati Gunawan; Subagjo Subagjo
ASEAN Journal of Chemical Engineering Vol 18, No 1 (2018)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Future fuel scarcity issue has become major concern for many energy security policies. As a very potential process to produce fuel, Fischer-Tropsch synthesis (FTS) with cobalt-based catalyst has been developed to produce wax as feedstock for further catalytic cracking. Therefore, this research was conducted to observe Co/Al2O3 catalyst properties enhancement through support pre-treatment using NH4NO3 and Cu promoter addition toward higher activity and selectivity. Catalysts were prepared by dry impregnation method. XRD, BET and TPR analyses were performed to characterize catalysts properties. Activity tests showed CO conversion, H2 conversion and selectivity of C5+ were in the range of 25.1% to 96.2%, 24.2% to 83.7% and 53.5% to 75.9% respectively. Crystallography measurements exhibited 8.6-9.8 nm cobalt particles size. In this study, FTS was evaluated by using fixed-bed reactor at 20 bar, 250 C, and WHSV of 1500 ml/g.cat/h-1. Support pre-treatment increased the pore size of γ-Al2O3 and slightly enlarged cobalt diameter. While addition of Cu improved the reducibility of the catalyst.

Methanol Dehydration to Dimethyl Ether over Modified γ-Al2O3 with Acid, Base and Zeolite (NaA and NaX) Maria Ulfah; Hendra Suherman; Melia Laniwati; IGBN Makertihartha; Subagjo Subagjo
ASEAN Journal of Chemical Engineering Vol 20, No 2 (2020)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.51354

The effect of acids, bases, zeolite NaA and zeolite NaX impregnation to g-Al2O3 on the catalyst characteristics and activity against methanol dehydration reaction were investigated. The catalyst characteristics include N2 physisorption, X-ray diffraction (XRD), and temperature-programmed desorption of ammonia (NH3-TPD) in addition to catalytic dehydration of methanol performed in a micro fixed-bed reactor at 270°C and 1 atm. The results of XRD characterization showed no changes related to the modification of alumina over acids, bases, and zeolite NaA and zeolite NaX. Therefore, the modification did not have any effect on the crystalline structure of alumina. The textural and surface acidity of g-Al2O3 changed post addition of acids, bases, zeolite NaA and zeolite NaX. NH3-TPD analysis results demonstrated that synthesized g-Al2O3 has three types of acid sites: weak, medium, and strong; however, the weak acid sites were not observed on alumina catalysts modified phosphate, KOH, zeolite NaA, and zeolite NaX. Furthermore, the concentration of strong acid sites increased in the catalyst containing KOH. The catalytic test results showed that the untreated g-Al2O3 catalyst gave prominent activity in dehydration of methanol compared to the treated catalyst following the number and strength of acid sites.

Karakterisasi dan Kinetika Kalsinasi Dolomit Winny Wulandari; Subagjo Subagjo; Adnanta Rio; Pratama Istiadi
Jurnal Teknologi Bahan dan Barang Teknik Vol 8, No 2 (2018)
Publisher : Balai Besar Bahan dan Barang Teknik

Calcination is a key processing step to increase added value of dolomite to many end-products, including as a feedstock for magnesium metal, as a flux for steelmaking, and refractory bricks. This research dealt with calcination of dolomite from Gresik, East Java. Calcination was carried out in a tubular reactor with a diameter of 3 cm, at an atmospheric pressure and using nitrogen as an elusion gas with the rate of 50 mL/min. Reaction temperature was varied at 700, 800 and 900°C and the reactions were carried out for 1, 2, 3, and 4 hours. The conversion of dolomite calcination reaches 98 to 99% as the calcination conducted at 800 and 900°C. The experimental results were presented using various kinetics models. The diffusion Ginstling-Brounshtein model was found as the best for describing the calcination reaction, which implied the reaction was controlled by internal diffusion of reactants. For the Ginstling-Brounshtein model, the apparent activation energy of dolomite calcination was found to be 77.07 kJ/mol.Kalsinasi merupakan salah satu proses untuk meningkatkan nilai tambah dolomit menjadi berbagai jenis produk akhir, seperti bahan baku pembuatan logam magnesium, sebagai fluks untuk pembuatan baja, serta batu bata tahan api. Penelitian ini dimaksudkan untuk menentukan kinetika kalsinasi dolomit Gresik, Jawa Timur. Temperatur reaksi divariasikan 700, 800 dan 900˚C. Kalsinasi dilakukan selama 1, 2, 3, dan 4 jam di dalam sebuah reaktor tubular dengan diameter 3 cm pada tekanan atmosfer. Reaksi kalsinasi dilakukan dalam kondisi gas nitrogen yang dialirkan sebagai gas-elusi dengan laju alir 50 mL/menit. Konversi dolomit mencapai 98 hingga 99% ketika kalsinasi dilakukan pada temperatur 800 dan 900˚C. Model difusi Ginstling-Brounshtein dapat dijadikan model yang paling sesuai untuk menggambarkan reaksi kalsinasi yang dikendalikan oleh perpindahan massa difusi di dalam partikel. Untuk model Ginstling-Brounshtein, energi aktivasi kalsinasi dolomit terhitung sebesar 77,07 kJ/mol.

Deaktivasi Katalis Konverter-Hidrogen Di Pabrik Urea Kaltim-3 Agus Subekti; Achmad Syamsul Arief; Praharso Praharso; Subagjo Subagjo
Bulletin of Chemical Reaction Engineering & Catalysis 2007: BCREC: Volume 2 Issues 2-3 Year 2007 (October 2007)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.2.2-3.7130.52-55

Di pabrik urea, konverter-hidrogen adalah satu reaktor yang berfungsi untuk mengkonversi hidrogen yang terikut dalam karbondioksida dengan cara mengoksidasi dengan udara, sehingga karbondioksida umpan reaktor urea itu hanya mengandung tidak lebih dari 100 ppm hidrogen. Konversi dilangsungkan pada tekanan 145 kg/cm2 dan suhu umpan reaktor 130°C, menggunakan katalis platinum berpenyangga alumina (0,3%Pt/Al2O3). Dalam dua tahun terakhir, terjadi kenaikan kandungan hidrogen dalam karbondioksida umpan konverter-hidrogen Kaltim-3 yang menyebabkan peningkatan temperatur keluaran konverter dari biasanya sekitar 152oC menjadi sekitar 190°C. Hasil analisis kadar Pt, luas permukaan katalis dan dispersi Pt terhadap katalis-baru dan katalis-terpakai menunjukkan bahwa katalis konverter-hidrogen Kaltim-3 telah terdeaktivasi. Oleh karena itu, pada kesempatan perbaikan-tahunan Juli 2006 yang lalu, katalis tersebut telah diganti dengan yang baru. Selain itu telah dilakukan pula perbaikan kondisi operasi di pabrik amoniak Kaltim-3, sehingga kadar H2 dalam aliran CO2 umpan pabrik urea Kaltim-3 menjadi normal kembali (0,4%). Dengan tindakan-tindakan tersebut, sejak Agustus 2006 yang lalu konverter hidrogen Kaltim-3 dapat beroperasi secara normal kembali. © 2007 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0)

Co-Authors Achmad Syamsul Arief Adnanta Rio Agus Subekti Ahlul Hafizan Resha Anita K. Wardani Anita K. Wardani, Anita K. Danu Ariono Danu Ariono David Bahrin Deviana Pramitasari Endang Sri Rahayu Endar Puspawiningtiyas Fitri Rumiani Galang Putra Persada Hendra Suherman Herri Susanto I Gede Wenten I.G.B Ngurah Makertihartha IGBN Makertihartha IGBN Makertihartha IGBN Makertihartha Kadja, Grandprix Thomryes Marth Kevin R. Lismana Kevin R. Lismana Khasin Fuadi Khasin Fuadi M. Effendy M. Effendy M. Effendy M. Effendy M. Effendy Maria Ulfah Meiti Pratiwi Melia L. Gunawan Melia Laniwati Melia Laniwati Gunawan Melia Laniwati Gunawan Melia Laniwati Gunawan Melia Laniwati Gunawan Mohammad Effendy Mohammad Effendy P.T.P. Aryanti P.T.P. Aryanti, P.T.P. Praharso Paharso Praharso Praharso Pratama Istiadi Rino R. Mukti Shelli R. Joscarita Shelli R. Joscarita, Shelli R. Syamsudin Syamsudin Syamsudin Syamsudin T. Walmiki Samadhi Tatang Hernas Soerawidjaja Temy Nurfahmiawati Tirto Prakoso Tjokorde Walmiki Samadhi Tjokorde Walmiki Samadhi Tjokorde Walmiki Samadhi Tobias Richards Ulfah, Maria Vita Wonoputri Vita Wonoputri Widdy Andya Fanny Winny Wulandari, Winny Yazid Bindar Yazid Bindar Yazid Bindar Yazid Bindar Yogi W. Budhi Yogi W. Budhi Yogi Wibisono Budhi Zaky Al Fatony

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