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Reaktor
Published by Universitas Diponegoro
ISSN : 08520798     EISSN : 24075973     DOI : https://doi.org/10.14710/reaktor.xx.x.xx-xx
Core Subject : Science, Engineering,
Chemical Engineering, Chemistry & Bioengineering Control & Systems Engineering Energy Materials Science & Nanotechnology
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
Arjuna Subject : Teknik (semua kategori) - Teknik (Lain-Lain)
Articles 7 Documents
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Search results for , issue "Volume 13, Nomor 3, Juni 2011" : 7 Documents clear
AKTIVASI ZEOLIT ALAM SEBAGAI ADSORBEN PADA ALAT PENGERING BERSUHU RENDAH Laeli Kurniasari; Mohammad Djaeni; Aprilina Purbasari
Reaktor Volume 13, Nomor 3, Juni 2011
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (588.321 KB) | DOI: 10.14710/reaktor.13.3.178-184

Abstract

ACTIVATION OF NATURAL ZEOLITE AS AN ADSORBENT FOR LOW TEMPERATURE DRYING SYSTEM. Drying is one process which is used in many industries, especially in food product. The process usually still has low energy efficiency and can make food deterioration because of the usage of high temperature. One alternative in drying technology is the use of zeolite as a water vapor adsorbent. This kind of drying method make it possible to operate in lower temperature, hence it will be suitable for heat sensitive product. Natural zeolit can be one promising adsorbent since it is spreadly abundant in Indonesia. Natural zeolite must be activated first before used, in order to get zeolite with high adsorption capacity. Activation process in natural zeolite will change the Si/Al ratio, polarity, and affinity of zeolite toward water vapor and also increase the porosity. Activation of natural zeolite can be done with two methods, chemical activation use NaOH and physical activation use heat. In the activation using NaOH, natural zeolite is immersed with NaOH solution 0.5-2N in 2 hour with temperature range 60-900C. The process is continued with the drying of zeolite in oven with 1100C for 4 hours. While in heat treatment, zeolit is heated into 200-5000C in furnace for 2-5 hours. SEM analysis is used to compare the change in zeolite morphology before and after each treatment, while to know the adsorption capacity of zeolite, the analyses were done in many temperature and relative humidity. Result gives the best condition in NaOH activation is NaOH 1N and temperature 700C, with water vapor loading is 0.171 gr/gr adsorbent. In heat treatment, the best condition is 3000C and 3 hours with loading 0.137 gr water vapor/gr adsorbent.  Pengeringan merupakan salah satu proses yang banyak digunakan pada produk pangan. Proses ini umumnya menyebabkan kerusakan pada bahan pangan, disamping masih rendahnya efisiensi energi. Salah satu alternatif pada proses pengeringan yaitu penggunaan zeolit sebagai adsorben uap air. Proses pengeringan dengan menggunakan zeolit sebagai adsorben ini memungkinkan operasi pengeringan dilakukan pada suhu rendah sehingga sesuai untuk bahan yang tidak tahan panas. Zeolit alam merupakan salah satu alternatif bahan adsorben. Akan tetapi zeolit ini harus diaktivasi terlebih dahulu untuk mendapatkan zeolit dengan kemampuan adsorpsi yang tinggi. Proses aktivasi pada zeolit akan merubah rasio Si/Al zeolit, polaritas serta afinitas zeolit terhadap air dan meningkatkan pori-pori zeolit Adsorpsi zeolit alam dilakukan dengan dua cara yaitu dengan NaOH dan dengan panas. Pada aktivasi dengan NaOH, zeolit dicampur dengan NaOH 0,5-2N selama 2 jam pada suhu 60-900C. Sementara pada aktivasi fisis, zeolit dipanaskan pada 200-5000C selama 2-5 jam. Untuk mengetahui perubahan struktur pori zeolit maka dilakukan analisa SEM dan untuk mengetahui kemampuan adsorpsi zeolit maka dilakukan analisa daya adsorpsi zeolit terhadap uap air pada berbagai suhu dan berbagai kelembaban relatif. Hasil menujukkan bahwa pada aktivasi dengan NaOH diperoleh kondisi aktivasi terbaik adalah NaOH 1N pada pemanasan 700C dengan daya adsorpsi 0,171 gr uap air/gr adsorben. Sementara untuk aktivasi dengan panas, kondisi aktivasi terbaik adalah pemanasan 3000C selama 3 jam dengan daya adsorpsi 0,137 gr uap air/gr adsorben.
KINETIKA MIKRO DEKOMPOSISI METANA MENJADI KARBON NANOTUBE PADA PERMUKAAN KATALIS Ni-Cu-Al Praswasti Pembangun Dyah Kencana Wulan; Widodo Wahyu Purwanto; Yuswan Muharam
Reaktor Volume 13, Nomor 3, Juni 2011
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (310.558 KB) | DOI: 10.14710/reaktor.13.3.148-154

Abstract

MICRO KINETICS OF DECOMPOSITION OF METHANE TO CARBON NANOTUBES OVER NI-CU-AL CATALYST. The main focus of this research was to obtain micro kinetics decomposition of methane producing carbon nanotube on the surface of the Ni-Cu-Al catalyst. Experimental kinetics data collected at a temperature range of 650-750oC and pressure of one atmosphere. The preliminary test was conducted to obtain the kinetics are not influenced by external and internal diffusion limitations as well as inter-phase transfer. Kinetics data were tested by micro kinetic model derived from the catalyst surface reaction mechanism. The most appropriate kinetic model becomes the rate-limiting step of methane decomposition reaction. Results of preliminary experiment showed that the kinetics of the external diffusion effect is negligible at flow rates above 150 mL/min. Internal diffusion can be ignored with a catalyst under 0.25 mm in diameter with a weight of 0.04 grams of catalyst and contact time 2.5x10-4. Rate equation analysis shows that the rate-limiting step is the adsorption which indicates that intermediate consumption (CH4I + I Û CH3I + HI) is faster than the formation of intermediate (adsorption of methane, CH4 + I Û CH4I). The activation energy obtained for 34.628 kJ/mol and pre-exponential factor of 6.583x106.  Fokus utama penelitian ini adalah memperoleh kinetika mikro dekomposisi metana yang menghasilkan Carbon Nanotube pada permukaan  katalis Ni-Cu-Al. Data kinetika eksperimen diambil pada rentang temperatur 650-750oC dan tekanan 1 atmosfer. Percobaan pendahuluan dilakukan untuk memperoleh daerah kinetika yang tidak dipengaruhi oleh limitasi difusi eksternal dan internal serta perpindahan antar fasa.  Data kinetika  diuji dengan model kinetika mikro yang diturunkan dari mekanisme reaksi permukaan katalis. Model kinetika yang paling sesuai menjadi tahap pembatas laju reaksi dekomposisi metana. Hasil percobaan pendahuluan kinetika menunjukkan bahwa pengaruh difusi eksternal dapat diabaikan pada laju alir di atas 150 mL/menit. Difusi internal dapat diabaikan dengan menggunakan katalis berdiameter di bawah 0,25 mm dengan berat katalis 0,04 gram pada waktu kontak 2,5x10-4. Analisis persamaan laju menunjukkan bahwa tahap pembatas laju adalah tahap adsorpsi yang menunjukkan bahwa konsumsi intermediate (CH4I + I Û CH3I + HI) lebih cepat dari pembentukan intermediate (adsorpsi metana,CH4 + I Û CH4I). Energi aktivasi yang diperoleh sebesar 34,628 kJ/mol dan faktor pre-eksponensial 6,583x106.
KARAKTERISTIK FISIKOKIMIA PATI SAGU HASIL PENGERINGAN SECARA FLUIDISASI MENGGUNAKAN ALAT PENGERING CROSS FLOW FLUIDIZED BED BERTENAGA SURYA DAN BIOMASSA Abadi Jading; Eduard Tethool; Paulus Payung; Sarman Gultom
Reaktor Volume 13, Nomor 3, Juni 2011
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (913.368 KB) | DOI: 10.14710/reaktor.13.3.155-164

Abstract

PHYSICOCHEMICAL CHARACTERISTICS OF SAGO STARCH OBTAINED FROM FLUIDIZED BED DRYING USING SOLAR AND BIOMASS POWERED CROSS FLOW FLUIDIZED BED DRYER. The research aim is to study the comparative quality of sago starch drying results using cross flow fluidized bed dryer powered by solar and biomass in conventional drying, particularly the chemical composition and physicochemical characteristics. This research was conducted through a drying phase of wet sago starch using a cross flow fluidized bed dryer, and drying in conventional as well as dried sago starch quality testing results are drying. The results of this study indicate that dry sago starch which has been drained by means of cross flow fluidized bed dryer has a chemical composition that does not vary much with starch which is dried by conventional drying, so that the dried sago starch produced by the dryer is very good. On the other hand the use of dryers is the more correct because the physicochemical properties of sago starch using a low drying temperature and drying time is short. Tujuan penelitian ini adalah mempelajari perbandingan kualitas pati sagu hasil pengeringan menggunakan alat pengering cross flow fluidized bed bertenaga surya dan biomassa dengan pengeringan secara konvensional, khususnya komposisi kimia dan karakteristik fisikokimia. Penelitian ini dilakukan melalui beberapa tahapan yaitu pengeringan pati sagu basah menggunakan alat pengering cross flow fluidized bed, pengeringan secara konvensional serta pengujian kualitas pati sagu kering hasil pengeringan. Hasil dari penelitian ini menunjukkan bahwa pati sagu kering yang telah dikeringkan dengan alat pengering cross flow fluidized bed memiliki komposisi kimia yang tidak berbeda jauh dengan pati yang dikeringkan dengan cara pengeringan secara konvensional, sehingga pati sagu kering yang dihasilkan oleh alat pengering tersebut sangat baik. Di sisi lain penggunaan alat pengering ini semakin memperbaiki sifat fisikokimia pati sagu sebab menggunakan suhu pengeringan yang rendah dan waktu pengeringan yang singkat.   Kata Kunci: pengering unggun terfluidakan; fisikokimia; pati sagu
PRODUKSI ANTIBIOTIKA OLEH Bacillus subtilis M10 DALAM MEDIA UREA-SORBITOL Supartono Supartono; Nanik Wijayati; Lina Herlina; Enny Ratnaningsih
Reaktor Volume 13, Nomor 3, Juni 2011
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (348.974 KB) | DOI: 10.14710/reaktor.13.3.185-193

Abstract

PRODUCTION OF ANTIBIOTICS BY Bacillus subtilis M10 IN UREA-SORBITOL MEDIUM. Infection diseases still become the main health problems that suffered by people in Indonesia. Besides, there were many pathogen bacteria found to be resistant to the some antibiotics. Therefore, the efforts to get a new antibiotic require to be done continuously. A new local strain of Bacillus subtilis BAC4 has been known producing an antibiotic that inhibit Serratia marcescens ATCC 27117 growth. To make efficient the local strain, mutation on Bacillus subtilis BAC4 was done by using acridine orange and a mutant cell of Bacillus subtilis M10 that overproduction for producing antibiotic was obtained. Nevertheless, the production kinetics of antibiotic by this mutant has not been reported. The objective of this research was to study the production kinetics of antibiotic by Bacillus subtilis M10 mutant. The production of antibiotic was conducted using batch fermentation and antibiotic assay was performed with agar absorption method using Serratia marcescens ATCC 27117 as bacteria assay. Research result provided that Bacillus subtilis M10 mutant with overproduction of antibiotic produced an antibiotic since 8th hour’s fermentation and optimum of it production was at 14th hours after inoculation.  Penyakit infeksi masih menjadi masalah yang utama diderita oleh masyarakat Indonesia. Di samping itu, banyak bakteri patogen yang ditemukan resisten terhadap beberapa antibiotika. Oleh karena itu, upaya-upaya untuk mendapatkan antibiotika baru perlu dilakukan secara terus-menerus. Suatu galur lokal baru Bacillus subtilis BAC4 teridentifikasi memproduksi senyawa antibiotika yang menghambat pertumbuhan Serratia marcescens ATCC27117. Untuk memberdayakan galur tersebut, terhadap Bacillus subtilis BAC4 dilakukan mutasi dengan larutan akridin oranye dan diperoleh mutan Bacillus subtilis M10 yang memproduksi antibiotika berlebihan. Namun, kinetika produksi antibiotika oleh Bacillus subtilis M10 belum pernah dilaporkan. Penelitian ini bertujuan untuk mempelajari kinetika produksi antibiotika oleh mutan Bacillus subtilis M10. Bacillus subtilis M10 difermentasikan ke dalam media urea-sorbitol dan diamati kemampuan produksi antibiotikanya menggunakan Serratia marcescens ATCC 2711 sebagai bakteri uji. Hasil penelitian menunjukkan bahwa mutan Bacillus subtilis M10 memproduksi antibiotika sejak jam ke 8, dan produksi optimumnya terjadi pada jam ke 14 setelah inokulasi.
PENGARUH PROSES PENGERINGAN RIMPANG TEMULAWAK (Curcuma xanthorriza ROXB) TERHADAP KANDUNGAN DAN KOMPOSISI KURKUMINOID Bambang Cahyono; Muhammad Diah Khoirul Huda; Leenawaty Limantara
Reaktor Volume 13, Nomor 3, Juni 2011
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (325.395 KB) | DOI: 10.14710/reaktor.13.3.165-171

Abstract

EFFECT OF DRYING PROCESSES ON CURCUMINOID CONTENT AND COMPOSITION OF TEMULAWAK (Curcuma xanthorriza ROXB) RHIZOMES. Curcuminoid a yellow coloring agent of turmeric is known to have many benefits in food and medicinal industries. This compound can be isolated by simple extraction from fresh rhizome or symplicia. The research of comparing qualitative and quantitative of curcuminoid in different drying process has not yet been published. Drying methods used in this research were done in an oven at 60°C and under 30-watt electrical lamp at ±30°C. Each method was carried out in time variation of 1, 3, and 5 days. Extraction of curcuminoid was done using ethanol 95% followed by fat reduction process using petroleum ether. Curcuminoid analysis was done by TLC, UV-Visible spectrophotometer and HPLC. The result showed that the water content of all samples was approximately 4.06%-7.76%. TLC analysis identified the presence of two dominant components in the curcuminoid with the Rf values of 0.37 and 0.15. The UV-Visible spectra indicated that simplicia would give more result in curcuminoid than fresh rhizome. There were 4 substances detected in HPLC analysis, they were curcumin 61-67%, demetoxycurcumin 22-26%, bisdemetoxycurcumin 1-3%, and curcuminoid derivative 10-11%. In addition, drying on oven resulted brighter and crispier simplicia than drying under lamp.  Kurkuminoid yang merupakan zat utama yang berwarna kuning dalam temulawak telah diketahui memiliki banyak manfaat di bidang kesehatan dan makanan. Bahan ini dapat diisolasi dari bahan segar atau simplisia kering melalui ekstraksi. Riset yang mencoba membandingkan kualitas dan kuantitas kurkuminoid akibat perlakuan panas pada saat pembuatan simplisia hingga sekarang belum pernah dilakukan. Penelitian dimulai dengan pengeringan temulawak segar setelah dirajang pada oven suhu 60°C dan pada pengeringan lampu listrik 30 watt pada suhu ± 30°C. Masing-masing metode dilakukan variasi lama pengeringan 1, 3, 5 hari. Ekstraksi kurkuminoid dilakukan menggunakan etanol 95% dan defatisasi menggunakan petroleum eter, sedangkan analisis kualtatif dan kuantitatif kurkuminoid direalisasikan dengan KLT, spektrofotometer UV-Tampak dan KCKT. Hasil penelitian menunjukkan bahwa kandungan air semua sampel sekitar 4,06%-7,76%. Analisis KLT mengidentifikasi adanya dua komponen dominan dalam kurkuminoid dengan nilai Rf 0,37 dan 0,15. Hasil analisis Spektrofotometri UV-tampak memberikan keenderungan bahwa kurkuminoid dari sampel kering lebih mudah terekstraksi daripada sampel basah. Kromatogram HPLC dapat mendeteksi adanya 4 senyawa yaitu kurkumin 61-67%, demetoksikurkumin 22-26%, bisdemetoksikurkumin 1-3%, dan turunan kurkuminoid 10-11%, urutan prosentase masing-masing komponen tetap sama selama proses pengeringan. Hasil penelitian ini juga telah dapat menunjukkan bahwa perbedaan kondisi operasi pengeringan sangat mempenaruhi penampakan simplisia yang dihasilkan, pengeringan oven memiliki warna lebih cerah dan  lebih meremah daripada pengeringan lampu.
MODEL ADSORPSI LANGMUIR GAS DINITROGEN MONOKSIDA DALAM SISTEM BIOFILTER DENGAN MEDIUM PUPUK KOMPOS Tania Surya Utami; Josia Simanjuntak; Heri Hermansyah; Mohamad Nasikin
Reaktor Volume 13, Nomor 3, Juni 2011
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (911.146 KB) | DOI: 10.14710/reaktor.13.3.172-177

Abstract

 LANGMUIR ADSORPTION MODEL FOR DINITROGEN MONOXIDE IN BIOFILTER SYSTEM USING COMPOST FERTILIZER MEDIUM. Nitrous oxide (N2O) is mostly emitted from various industrial processes and agricultural activities. This gas causes serious environmental problems and is considered as a dangerous pollutant. In the past, traditional control technologies, such as Selective Catalytic Reduction (SCR) and Selective Non-Catalytic Reduction (SNCR), were applied to control N2O emissions in some industries. However, these two processes required high temperatures and the use of catalysts. Economic and technical constraints in SCR and SNCR methods motivated researchers to develop new, cost-effective processes to remove N2O. Biofiltration is an emerging technology that offers a number of advantages over traditional methods of air pollution control. The purpose of this research is to modelise the biofiltration experimental results into the Langmuir adsorption model. This research is conducted in laboratory scale biofilter column, with parameters studied are effect of biofilter length and N2O gas flowrate. The result of the model is simulated into sensitivity analysis. The average Langmuir constant obtained in the model of the research is 16.006 liter/mol. Dinitrogen Monoksida (N2O) merupakan emisi dari proses industri dan kegiatan pertanian. Gas tersebut merupakan gas polutan berbahaya dan menyebabkan masalah lingkungan yang serius. Sebelumnya, teknologi kontrol tradisional seperti Selective Catalytic Reduction (SCR) dan Selective Non-Catalytic Reduction (SNCR) digunakan untuk mengontrol emisi N2O pada kegiatan-kegiatan industri. Akan tetapi, kedua proses ini membutuhkan suhu yang tinggi dan penggunaan katalis. Adanya masalah dari segi ekonomi dan teknis memotivasi peneliti untuk mengembangkan teknologi baru yang lebih murah dan efisien untuk menghilangkan N2O dari gas buangan. Pengolahan N2O secara biologis dalam proses biofiltrasi adalah salah satu alternatif ramah lingkungan yang dapat digunakan dalam pengelolaan emisi industri. Penelitian ini bertujuan untuk menggambarkan hasil biofiltrasi gas N2O dengan medium pupuk kompos dalam bentuk model adsorpsi Langmuir. Penelitian dilakukan dalam kolom biofilter skala laboratorium, dan parameter-parameter yang diteliti adalah pengaruh dari ketinggian biofilter dan laju alir gas N2O. Hasil dari pemodelan kemudian disimulasikan dalam analisis sensitivitas. Nilai konstanta Langmuir rata-rata yang didapatkan dari pemodelan penelitian ini adalah 16,006 liter/mol.
PLASTIC WASTE CONVERSION TO LIQUID FUELS OVER MODIFIED-RESIDUAL CATALYTIC CRACKING CATALYSTS: MODELING AND OPTIMIZATION USING HYBRID ARTIFICIAL NEURAL NETWORK – GENETIC ALGORITHM Istadi Istadi; Luqman Buchori; Suherman Suherman
Reaktor Volume 13, Nomor 3, Juni 2011
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (409.398 KB) | DOI: 10.14710/reaktor.13.3.131-139

Abstract

The plastic waste utilization can be addressed toward different valuable products. A promising technology for the utilization is by converting it to fuels. Simultaneous modeling and optimization representing effect of reactor temperature, catalyst calcinations temperature, and plastic/catalyst weight ratio toward performance of liquid fuel production was studied over modified catalyst waste. The optimization was performed to find optimal operating conditions (reactor temperature, catalyst calcination temperature, and plastic/catalyst weight ratio) that maximize the liquid fuel product. A Hybrid Artificial Neural Network-Genetic Algorithm (ANN-GA) method was used for the modeling and optimization, respectively. The variable interaction between the reactor temperature, catalyst calcination temperature, as well as plastic/catalyst ratio is presented in surface plots. From the GC-MS characterization, the liquid fuels product was mainly composed of C4 to C13 hydrocarbons.KONVERSI LIMBAH PLASTIK MENJADI BAHAN BAKAR CAIR DENGAN METODE PERENGKAHAN KATALITIK MENGGUNAKAN KATALIS BEKAS YANG TERMODIFIKASI: PEMODELAN DAN OPTIMASI MENGGUNAKAN GABUNGAN METODE ARTIFICIAL NEURAL NETWORK DAN GENETIC ALGORITHM. Pemanfaatan limbah plastik dapat dilakukan untuk menghasilkan produk yang lebih bernilai tinggi. Salah satu teknologi yang menjanjikan adalah dengan mengkonversikannya menjadi bahan bakar. Permodelan, simulasi dan optimisasi simultan yang menggambarkan efek dari suhu reaktor, suhu kalsinasi katalis, dan rasio berat plastik/katalis terhadap kinerja produksi bahan bakar cair telah dipelajari menggunakan katalis bekas termodifikasi Optimisasi ini ditujukan untuk mencari kondisi operasi optimum (suhu reaktor, suhu kalsinasi katalis, dan rasio berat plastik/katalis) yang memaksimalkan produk bahan bakar cair. Metode Hybrid Artificial Neural Network-Genetic Algorithm (ANN-GA) telah digunakan untuk permodelan dan optimisasi simultan tersebut. Inetraksi antar variabel suhu reaktor, suhu kalsinasi katalis, dan rasio berat plastik/katalis digambarkan dalam bentuk plot surface. Berdasarkan karakterisasi GC-MS, produk bahan bakar yang diperoleh terdiri dari komponen-komponen hidrokarbon C4-C13.

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