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Dessy Ariyanti
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Reaktor
Published by Universitas Diponegoro
Reaktor invites contributions of original and novel fundamental research. Reaktor publishes scientific study/ research papers, industrial problem solving related to Chemical Engineering field as well as review papers. The journal presents paper dealing with the topic related to Chemical Engineering including: Transport Phenomena and Chemical Engineering Operating Unit Chemical Reaction Technique, Chemical Kinetics, and Catalysis Designing, Modeling, and Process Optimization Energy and Conversion Technology Thermodynamics Process System Engineering and products Particulate and emulsion technologies Membrane Technology Material Development Food Technology and Bioprocess Waste Treatment Technology
Articles 530 Documents
PEMILIHAN ADSORBEN UNTUK PENJERAPAN KARBON MONOKSIDA MENGGUNAKAN MODEL ADSORPSI ISOTERMIS LANGMUIR Yuliusman Yuliusman; Widodo Wahyu Purwanto; Yulianto Sulistyo Nugroho
Reaktor Volume 14, No. 3, APRIL 2013
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (393.773 KB) | DOI: 10.14710/reaktor.14.3.225-233

Abstract

ADSORBENT SELECTION FOR CO ADSORPTION USING LANGMUIR ISOTHERMIC ADSORPTION MODEL. The objective of this research is to choose the adsorbent that can be applied to decrease toxicity level and to purify fire smoke. In case of fire, toxicity level is high due to carbon monoxide. Adsorbent is chosen based on its ability to adsorb carbon monoxide using volumetric method in constant temperature. Materials to be tested are natural zeolite, active carbon, TiO2, CuO, MgO. Due to existence of organic and mineral polluters, natural zeolite needs to be activated prior to adsorption test using fluoride acid (HF), chloride acid (HCl), ammonium chloride (NH4Cl) and followed by calcination process. Result shows that activation of natural zeolite can increase Si/Al ratio and surface area. According to Langmuir adsorption model obtained, adsorption capacity of active carbon and natural zeolite are the highest. At 1 atmospheric pressure, adsorption capacity are 0.0682 mmol/g for active carbon, 0.0464 for activated natural zeolite with particle size of 400 nm, and 0.0265 mmol/g for activated natural zeolite with particle size of (37-50) μm. Penelitian ini bertujuan untuk memilih adsorben yang dapat diaplikasikan untuk menurunkan tingkat racun dan menjernihkan asap kebakaran. Pada kasus kebakaran tingkat racun asap disebabkan tingginya kandungan karbon monoksida. Proses pemilihan adsorben dilihat pada kemampuan adsorben mengadsorpsi karbon monoksida, yang dilakukan dengan metode volumetrik pada temperatur konstan. Material yang diuji adalah zeolit alam, karbon aktif, TiO2, CuO, MgO. Zeolit alam banyak terdapat pengotor baik organik maupun mineral, oleh karena itu sebelum dilakukan uji adsorpsi, zeolit alam terlebih dahulu diaktifasi menggunakan larutan asam florida (HF), asam khlorida (HCl) dan larutan amonium khlorida (NH4Cl), dilanjutkan dengan proses kalsinasi. Hasil penelitian menunjukkan bahwa aktifasi zeolit alam dapat meningkatkan rasio Si/Al dan luas permukaan. Semua adsorben yang diuji mempunyai kemampuan mengadsorpsi karbon monoksida. Berdasarkan model adsorpsi Langmuir yang diperoleh, karbon aktif dan zeolit alam mempunyai kapasitas adsorpsi yang paling besar. Dengan menggunakan kondisi tekanan 1 atmosfir, kapasitas adsorpsi adalah 0,0682 mmol/g untuk karbon aktif, 0,0464 mmol/g untuk zeolit alam teraktifasi dengan ukuran partikel 400 nm dan 0,0265 mmol/g untuk zeolit alam teraktifasi dengan ukuran partikel (37-50) μm.
2-d mathematical and numerical modeling of fluid flow inside and outside packing in catalytic packed bed reactor L. Buchori; Y. Bindar; D. Sasongko; IGBN Makertihartha
Reaktor Volume 5 No. 1 Juni 2001
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (4840.618 KB) | DOI: 10.14710/reaktor.5.1.1-7

Abstract

Generally, the momentum equation of fluid flow in porous media was solved by neglecting the terms of diffusion and convection such as Ergun, Darcy, Brinkman and Forchheimer models. Their model primarily applied for laminar flow. It is true that these model are limited to condition whether the models can be applied. Analytical solution for the model type above is available only for simple one-dimensional cases. For two or three-dimentional problem, numerical solution is the only solution. This work advances the flow model in porous media and provide two-dimentional flow field solution in porous media, which includes the diffusion and convection terms. The momentum lost due to flow and porous material interaction is modeled using the available  Brinkman-Forchheimer equation. The numerical method to be used is finite volume method. This method is suitable for the characteristic of fluid  flow in porous media which is averaged by a volume base. The effect of the solid and fluid interaction in porous  media is the basic principle of the flow model in morous media. The Brinkman-Forchheimer consider the momentum lost term to be determined by a quadratic function of the velocity component. The momentum and the continuity equation are solved for two-dimentional cylindrical coordinat . the result were validated with the experimental data. The velocity of the porous media was treated to be radially oscillated. The result of velocity profile inside packing show a good agreement in their trend with the Stephenson and Steward experimental data. The local superficial  velocity attains its global maximum and minimum at distances near 0.201 and 0.57 particle diameter, dp. velocity profile below packing was simulated. The result were validated with Schwartz and Smith experimental data. The result also show an excellent agreement with those experimental data.Keywords : finite volume method, porous media, flow distribution, velocity profile
PROSES GLISEROLISIS MINYAK KELAPA SAWIT MENJADI MONO DAN DIACYL GLISEROL DENGAN PELARUT N-BUTANOL DAN KATALIS MgO Didi Dwi Anggoro; Faleh Setia Budi
Reaktor Volume 12, Nomor 1, Juni 2008
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (629.888 KB) | DOI: 10.14710/reaktor.12.1.22-28

Abstract

Indonesia merupakan salah satu negara penghasil minyak sawit terbesar di dunia. Lebih dari setengah produksinya digunakan untuk kebutuhan dalam negeri dan sisanya diekspor. Produk turunan minyak sawit seperti Mono-Di Acyl Gliserol (MAG-DAG) mempunyai nilai ekonomi yang  tingg dan selama ini Indonesia masih mengimpornya. MAG- DAG dibuat dari senyawa gliserida yang banyak terdapat dalam bahan minyak atau lemak, seperti minyak kelapa sawit, dengan gliserol. Tujuan dari penelitian ini adalah Studi eksperimen produksi MAG-DAG dari minyak kelapa sawit pada suhu rendah (2000C) dengan reaktor batch skala laboratorium, dan mengetahui pengaruh variabel-variabel proses. Variabel berubah yang digunakan adalah suhu (70 oC, 90 oC, dan 110 oC), rasio gliserol/CPO (3, 4, dan 5), dan jumlah katalis (2% w, 3% w, dan 4% w). Sedangkan variabel tetapnya adalah berat total campuran reaksi 300 gram, kecepatan pengadukan 400 rpm, waktu 4 jam dan jumlah pelarut 20 ml/10 gram CPO. Dari hasil pengolahan data menggunakan program STATISTICA 6 diperoleh kondisi operasi optimum dicapai pada suhu sekitar 70-1000C, rasio gliserol/CPO sekitar 3,5-4,5 serta katalis pada kisaran 2,5-4% dengan konversi yang diperoleh sekitar 93-98%. Dengan adanya penambahan pelarut n-Butanol, reaksi dapat dijalankan pada suhu yang lebih rendah (di bawah 2000C) tanpa menurunkan konversi yang diperoleh.
Effect of Extraction Time on Unreacted Oil Removal in Biodiesel Purification Using Deep Eutectic Solvent Helda Niawanti; Siti Zullaikah
Reaktor Volume 18 No. 2 June 2018
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (446.55 KB) | DOI: 10.14710/reaktor.18.2.122-127

Abstract

Rice bran oil (RBO) based biodiesel contains unreacted oil such as monoglyceride (MG), diglyceride (DG) and triglyceride (TG) to be purified. The liquid-liquid extraction (LLE) method was used for purification using Deep Eutectic Solvent (DES). The objective of this work was to study the effect of extraction time on unreacted oil removal. RBO containing 16.49% oil with free fatty acids (FFA) content of 44.75%. Acid catalyzed methanolysis was used for biodiesel production under operating conditions: T = 60°C, t = 8 hours, molar ratio of oil/methanol  was 1/10, H2SO4 1% w/w of RBO. Crude biodiesel containing 89.05% fatty acid methyl ester (FAME), 0.05% FFA, TG 4.03%, DG 4.01%  and MG 0.30%. DES was made from choline chloride and ethylene glycol with 1/2 molar ratio, while molar ratio of biodiesel/DES was 1/2. The extraction time was varied from 15 to 240 minutes at 30°C. The highest TG, DG and MG removal were obtained at 240 minutes, they were 3.01%, 0.22% and 0.03%, respectively. FAME and FFA content were 96.55% and 0.03%. Keywords: biodiesel; DES; extraction; unreacted oil; purification
ANALISA ENERGI DAN EKSERGI PADA PENGERINGAN TEPUNG TAPIOKA MENGGUNAKAN PENGERING KONTINYU UNGGUN FLUIDISASI GETAR Suherman Suherman; Rona Trisnaningtyas
Reaktor Volume 16 No.1 Maret 2016
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (760.418 KB) | DOI: 10.14710/reaktor.16.1.24-31

Abstract

Energy and exergy analysis of cassava starch drying in continuous vibrated fluidized bed dryer were carried out to assess the performance of the system in terms of energy utilization ratio, energy efficiency, exergy inflow and outflow, exergy loss, and exergetic efficiency. The results showed cassava starch has starch content 87%, degree of whiteness 95%, negative fiber content, sperichal granula with average diameter12.32 μm, orthorhombic crystal structure and crystal size 47.467 nm . Energy utilization and energy utilization ratio increased from 0.08 to 0.20 J/s and 0.35 to 0.4 as the drying temperature  increased from 50 to 70 oC. Energy efficiency increased from 13.80 % to 23.31 %, while exergy inflow, outflow, and losses increased from 4.701 to 14.678, 2.277 to 6.344, and 2.424 to 8.334 J/s respectively in the above temperature range. Exergetic efficiency decreased with increase in drying air temperature, while exergetic improvement potential increased with increased drying air temperature. Keywords: Cassava starch, continuous drying, energy and exergy analysis, vibrated fluidized bed Abstrak Analisis energi dan eksergi pengeringan pati tapioka menggunakan pengering kontinu unggun fluidisasi getar, telah dilakukan untuk menilai kinerja sistem dalam bentuk utilisasi energi, efisiensi energi, eksergi masuk dan keluar, eksergi hilang dan efisiensi eksergi. Hasil analisis pati memiliki kandungan starch 87%, tingkat keputihan 95%, kandungan serat negatif, bentuk partikel granular spherical dengan diameter 12,32 μm, struktur kristal orthorhombic dan ukuran kristal sebesar 47,467 nm. Peningkatan suhu pengering dari 50 menjadi 70 0C akan meningkatkan utilisasi energi dan rasio utilisasi energi dari 0,08 menjadi 0,20 J/s dan 0,35 menjadi 0,4. Efisiensi energi meningkat dari 13,80% hingga 23,31%, sedangkan eksergi masuk dan keluar, eksergi hilang meningkat dari 4,701 menjadi 14,678, 2,277 menjadi 6,344, dan 2,424 menjadi 8,334 J/s. Efisiensi eksergi menurun dengan naiknya suhu sedangkan potensi pengembangan eksergi meningkat dengan naiknya suhu. Kata kunci:. Analisis energi dan eksergi, pati tapioka, pengeringan kontinu, unggun fluidisasi getar
Peningkatan Mutu Heavy Gas Oil (HGO) Secara Ekstraksi Cair-Cair Dengan Solven Dimethylsulfoxide (DMSO) B. Jos
Reaktor Volume 6 No. 2 Desember 2002
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (3029.619 KB) | DOI: 10.14710/reaktor.6.2.92-95

Abstract

Heavy gas oil (HGO) merupakan salah satu bahan dasar untuk bahan bakar mesin diesel/solar yang semakin meningkat kebutuhannya dari tahun ke tahun. Untuk meningkatkan mutu solar salah satu upaya yang dapat dilakukan adalah melalui pengurangan kadar senyawa aromatis dari HGO yang dapat mempengaruhi kualitas penyalaannya. Dalam penelitian ini pengambilan kandungan senyawa C aromatis dalam HGO dilakukan melalui operasi ekstraksi cair-cair dengan menggunakan Dimethylsulfoxide (DMSO) sebagai solven. Selanjutnya HGO yang diinginkan dianalisa sifat-sifat fisisnya. Hasil penelitian menunjukkan semakin besar waktu kontak, temperatur ekstraksi dan perbandingan solven-feed maka akan semakin banyak senyawa aromatis yang dapat terambil, akibatnya harga indeks diesel juga akan semakin meningkat. Kondisi optimum diperoleh jika harga indeks diesel tidak mengalami peningkatan lagi yaitu dengan waktu ekstraksi selama 10 menit pada temperature  40 0C dan perbandingan solven-feed = 1,2.Kata kunci : ekstraksi cair-cair, HGO, senyawa aromatis, solven
SINTESIS TURUNAN POLIEUGENOL SEBAGAI CARRIER BAGI RECOVERY LOGAM BERAT DENGAN TEKNIK MEMBRAN CAIR M. Cholid Djunaidi; Retno A. Lusiana; Pratama J. Wibawa; Dwi Siswanta; Jumina Jumina
Reaktor Volume 13, Nomor 1, Juni 2010
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (373.388 KB) | DOI: 10.14710/reaktor.13.1.16-23

Abstract

Telah dilakukan sintesis senyawa asam poliuegenoksi asetat dan polieugenoksi asetil piridil karbinolat (suatu turunan polieugenoksi asetat dengan gugus aktif N) dari eugenol. Hasil sintesis digunakan sebagai ekstraktan logam berat dengan metode transport membran cair. Analisis struktur polimer yang terbentuk dilakukan dengan spektrometer infra merah, 1H NMR, KLT, dan uji kelarutan. Penentuan berat molekul relatif polimer menggunakan metode viscometer Ubbelohde. Transport logam dilakukan dengan Membran Cair Ruah (BLM) menggunakan sel gelas tipe U terhadap campuran logam Cu (II), Fe (III), Ni (II), Cd (II), Zn (II), dan Cr (III) kesemuanya dalam bentuk garam klorida. Transport dilakukan pada fasa umpan dan penerima HCl, konsentrasi logam masing-masing 50 ppm. Penentuan konsentrasi ion logam di fasa penerima sebelum dan sesudah transport dilakukan dengan spectrofotometer serapan atom, sedangkan perubahan pH yang menyertai diukur dengan pH meter. Hasil sintesis polieugenoksi asetat dan polieugenoksi asetil piridil karbinolat berupa serbuk amorf berwarna merah bata sampai coklat tua, dengan berat molekul 5.980.854 gram/mol dan 5.602.282 gram/mol. Hasil transport terhadap campuran logam menunjukkan polieugenoksi asetat dan polieugenoksi asetil piridil karbinolat dengan gugus N hasil sintesis mampu mentransferkan  campuran logam ke fasa penerima dengan urutan logam hard  (Cr (III) dan Fe (III)) > logam borderline (Ni (II), Zn (II) dan Cu (II)), logam soft Cd (II).
Outdoor Closed System of Algal Mass Culture : In Sight of Comparison on Vertical and Horizontal Photobioreactor for Cultivating the Spirulina sp. Hilda Farida; Puspita Sari Harahap; Rifana Sobari; Rudyanto Gunawan; Delicia Yunita Rahman; Dwi Susilaningsih
Reaktor Volume 19 No. 2 June 2019
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (505.913 KB) | DOI: 10.14710/reaktor.19.2.54-61

Abstract

Spirulina are multiceluller and filamentous blue-green algae that has gained considerable popularity in the health food industry and increasingly as a protein and vitamin supplement to aquaculture diets. The challenge for economically and fulfill the requirement for food and medical purposes has create many ways for mass-growth production, that possibly cultivated in the open-system (such as a raceway pond) or closed-system photobioreactors (such as tubular, bubble-column, airlift, flat-panel, and vertical). the cultivation of teh Spirulina on the vertical and horizontal photobioreactor has been studied. The photobioreactor, namely BJVP and BJHP, has a design to be less energy consumption using the air bubbling or circular paddle. The observation was conducted in a whole year with parameters of rainfall, temperature, light intensity, pH, and salinity. Result  showed that cultivation of Spirulina on the vertical photobioreactor growth faster than teh horizontal photobioreactor systems and the yield of biomass was about 0.94 gDW/L. Average of temperature ranges of BJHP were 31.0C-35.5C, salinities were 35 per mil level, pH were 8.55-10.86, and light intensity were 427-2001 umol photon s-1m-2. Whereas the BJVP has averages temperature range of 31.4C-33.9C, salinity 33-35 per mil level, pH 8.46-10.75, and light intensity 532-2062 umol photon s-1m-2. The proximate analyses of biomass from BJVP cultivation shows has tendency higher protein content compared to BJHP. The optimization of both reactors has continuing evaluated in order to get the optimum parameters required for economically Spirulina cultivation systems.Keywords: Spirulina, BJVP, BJHP, outdoor mass cultivating system, photobioreactor.
BIODELIGNIFIKASI ENCENG GONDOK UNTUKMENINGKATKAN DIGESTIBILITAS PADA PROSESHIDROLISIS ENZIMATIK Eka Sari; S Syamsiah; Hary Sulistyo; Muslikhin Hidayat
Reaktor Volume 17 No.1 Maret 2017
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (288.351 KB) | DOI: 10.14710/reaktor.17.1.54-60

Abstract

Abstract  Water hyacinth is one of lignocellulose that has potential to bioethanol feedstocks. This is due to the high content of cellulose and hemicellulose its rapid growth and the plant is abundant in nature. Bioconversion of water hyacinth begins with biodelignification process. This biodelignification aims to remove lignin and reduce crystallinity  of cellulose and hemicellulose to increase its digestibility in enzymatic hydrolysis processes. The purpose of this study was to evaluate the effect of biodelignification of water hyacinth using  fungi  and the effect on the digestibility of water hyacinth in the enzymatic hydrolysis process. In this study, Biodelignification using Solid State Fermentation (SSF) method using Phanerochaete Chrysosporium (PC). Hyacinth is inserted in a bioreactor and incubated for 28 days. The analysis of composition of water hyacinth is conducted every 4 days. After the biodelignification process followed by hydrolysis process using cellulase enzyme. Glucose generated from this hydrolysis process will be analyzed using the Somogyi Nelson method. The results show that biodelignification process can improve the digestibility of water hyacinths characterized by increased glucose yield. Without biodelignification process, glucose yield only reached 3.98%. After biodelignification prior to the hydrolysis process, the highest glucose yield was achieved at 67.66% for 16 days incubation. Keywords: biodeglinification;glucose;hydrolysis;lignin; cellulast Abstrak Enceng gondok adalah salah satu lignoselulosa yang berpotensi untuk dijadikan bahan baku bioetanol. Hal ini disebabkan oleh kandungan selulosa dan hemiselulosa yang tinggi dan pertumbuhannya yang cepat sehingga ketersediaannya di alam sangat melimpah. Biokonversi enceng gondok dimulai dengan proses biodelignifikasi. Biodelignifikasi ini bertujuan menghilangkan lignin dan mengurangi kristalinitas selulosa dan hemiselulosa untuk meningkatkan digestibilitasnya pada proses hidrolisis enzimatik. Tujuan dari penelitian ini adalah mengevaluasi pengaruh biodelignifikasi enceng gondok dengan jamur terhadap digestibilitas enceng gondok pada proses hidrolisis enzimatik. Biodelignifikasi pada penelitian ini menggunakan metode Solid State Fermentation (SSF) menggunakan jamur Phanerochaete Chrysosporium (PC). Enceng gondok dimasukan dalam sebuah bioreaktor dan diinkubasi selama 28 hari. Analisis perubahan komposisi enceng gondok dilakukan setiap 4 hari. Setelah proses biodelignifikasi dilanjutkan dengan proses hidrolisis menggunakan enzim selulase. Glukosa yang dihasilkan dari proses hidrolisis ini akan dianalisis menggunakan metode Somogyi Nelson. Hasil penelitian menunjukkan bahwa proses biodelignifikasi dapat meningkatkan digestibilitas enceng gondok yang ditandai dengan meningkatnya yield glukosa. Tanpa proses biodelignifikasi, yield glukosa hanya mencapai 3,98%. Setelah dilakukan biodelignifikasi sebelum proses hidrolisis maka yield glukosa tertinggi dicapai sebesar 67,66% selama 16 hari inkubasi. Kata kunci:biodeglinifikasi;glukosa;hidrolisis;lignin; selulase
OPTIMASI PRODUKSI PULP FORMACELL DARI TANDAN KOSONG KELAPA SAWIT (TKKS) DENGAN METODE PERMUKAAN RESPON Sri Hidayati; Ahmad Sapta Zuidar; Ahmad Fahreza
Reaktor Volume 16 No.4 Desember 2016
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (491.128 KB) | DOI: 10.14710/reaktor.16.4.161-171

Abstract

ABSTRACT Empty oil-palm bunches (EOPB) contains more enough cellulose so that it can be made as an alternative pulp production.  One of the process of pulp production which friendly environment is by using acetate acid and formic acid called by formacell process.  The aims of the research is to got optimation models of formic acid concentration, HCl concentration and cooking duration for the EFB pulp production.  The optimum result of the EOPB pulp production were 75% of cellulose, 8% of hemiselulosa, 10% of  lignin, and 80% of yield with the optimum concentration 20% of formic acid, 0,5% of HCl, and 2 hour of cooking duration.   Keyword : pulp formacell, EFB, RSM.   ABSTRAK Tandan kosong kelapa sawit (TKKS) mengandung kadar selulosa yang cukup tinggi sehingga dapat dijadikan sebagai bahan baku alternatif produksi pulp.  Salah satu proses produksi pulp ramah lingkungan yaitu dengan menggunakan campuran pelarut asam asetat dan asam formiat sebagai bahan pemasak yang disebut proses formacell.  Tujuan dari penelitian ini untuk mendapatkan model optimasi dari konsentrasi asam formiat, konsentrasi HCl dan lama pemasakan untuk produksi pulp TKKS.  Konsentrasi pemasakan optimum terjadi pada konsentrasi asam formiat 20%, konsentrasi HCl 0,5%, dan lama pemasakan selama 2 jam dengan hasil optimum untuk produksi pulp TKKS yaitu 75 % selulosa, 8 % hemiselulosa, 10% lignin, dan 80% rendemen.   Kata kunci: pulp formacell, TKKS, RSM.    

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