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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 530 Documents
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EFFECT OF VARIATION OF MIXTURE LEACHATE WITH FLUID IN CATTLE RUMEN FORMATION OF BIOGAS Edhi Sarwono; Rika Endata; Budi Nining Widarti
Reaktor Volume 18 No. 3 September 2018
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (735.589 KB) | DOI: 10.14710/reaktor.18.03.171-175

Abstract

Abstract Composting in addition to producing fertilizers also produce leachate containing organic material, the leachate can pollute the environment if not managed properly. This study uses leachate as the main substance of biogas, mixed with cattle rumen fluid as the biostarter. This study aims to determine the optimal composition of biogas and to determine the effect of variations in the raw material mixture to the volume of biogas, volatile solid, temperature, pH, and flame. The study was conducted over 43 days using three types of batch digester with a capacity of 27 L. Comparison of a mixture consisting of leachate composting organic waste with cattle rumen fluid in each digester with variations in material composition of the mixture of 70%: 30%, 50%: 50%, 100%: 0%. During the study was observed it the volume of biogas daily, daily pH, temperature daily, weekly flame test and volatile solid test every 10 days. The volume of biogas using the principle of cylinder volume and volatile solid test using USEPA 1684 method. The results show the variation of 70%:30%, which resulted in a final volume of 2.78 L of gas, as well as a decrease in the volatile solid 23.29%, 12.82% increase in the pH. In a variation of 50%:50% produces a final volume of gas that is 0.537 L, as well as a decrease in volatile solid 42.35%, 12.82% increase in the pH. Variations 100%:0% produces a final volume of gas that is 1,247 L, a decrease in volatile solid 21.83%, 5.19% increase in the pH. All three digesters are at mesophilic temperatures and produce blue flame. Based on the results of this study concluded that the composition of the mixture that are in the most optimal is composition of 70%:30%. Keywords : biogas, rumen fluid beef, lindi organic waste composting
PENGARUH CO-PRECIPITATION BESI KLORIDA TERHADAP KINERJA LUMPUR AKTIF PADA PROSES PENGOLAHAN AIR LIMBAH DOMESTIK SINTETIK Dian Fatikha Aristiami; I Nyoman Widiasa
Reaktor Volume 15 No.3 April 2015
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (595.491 KB) | DOI: 10.14710/reaktor.15.3.182-189

Abstract

The increase of population leads to an increase of the quantity of domestic wastewater. Activated sludge system is the most cost-efective to treat the domestic wastewater treatment. This study is aimed to evaluate the co-precipitation coagulant effect of FeCl3 on the growth of activated sludge, settling characteristics of the activated sludge, and effluent quality. sludge sedimentation characteristics (settling) as well as on the effluent quality. The activated sludge systems were operated in batch mode and synthetic domestic wastewaters with C:N:P ratio of 100:5:1 were used as feed wastewater. The growth of activated sludge was based on concentration of Mixed Liquor Suspended Solid (MLSS), settling characteristics of activated sludge was based on value of Sludge Volume Index (SVI), and effluent quality was based on turbidity, colour, N-ammonia concentration, and Chemical Oxygen Demand content. Results indicate that inhibition effect of FeCl3 to activated sludge activity was not significant at dosage ≤ 30 mg/L. Good settling characterisic (SVI 70-150 mg/L) was achieved at dosage of 20-30 mg/L. Finally, the best effluent quality, i.e. turbidity (9.4), colour (96), amonia removal (83.6%), and COD removal (72.97%), at dosage of 30 mg/L. Keywords: activated sludge; co-precipitation; domestic wastewater; wastewater treatment Abstrak Peningkatan jumlah penduduk mengakibatkan kenaikan jumlah air limbah domestik. Sistem lumpur aktif merupakan proses yang paling efektif untuk mengolah air limbah domestik. Penelitian ini bertujuan untuk mengevaluasi pengaruh co-precipitation koagulan FeCl3 terhadap pertumbuhan lumpur aktif, karakteristik pengendapan lumpur aktif, dan kualitas efluen. Sistem lumpur aktif dioperasikan secara curah dan umpan air limbah yang digunakan adalah air limbah domestik sintesis dengan rasio C:N:P = 100:5:1. Pertumbuhan lumpur aktif  berdasarkan konsentrasi Mixed Liquor Suspended Solid (MLSS), karakteristik pengendapan lumpur berdasarkan  nilai Sludge Volume Index (SVI), dan kualitas efluen berdasarkan tingkat kekeruhan, warna, kadar N-amonia dan kadar Chemical Oxygen Demand (COD). Hasil penelitian menunjukkan bahwa inhibisi FeCl3 terhadap aktivitas lumpur aktif tidak signifikan pada dosis ≤ 30 mg/L. Karakteristik pengendapan yang baik (SVI 70-150 mg/L) tercapai pada dosis 20-30 mg/L. Kualitas efluen terbaik, yaitu  kekeruhan (9,4),  warna (96), penyisihan amonia (83,6%) dan penyisihan COD (72,97%), pada dosis 30 mg/L. Kata kunci: lumpur aktif; co-precipitation; air limbah domestik; pengolahan air limbah  
Effect Of Polymer Molecular Weight On The Luminescence Properties Of Nanocomposite Zinc Oxide/Polyethylene Glycol M. Abdullah
Reaktor Volume 07 No. 1 Juni 2003
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (4055.96 KB) | DOI: 10.14710/reaktor.7.1.47-51

Abstract

Luminescence Properties Of Nanocomposite (Zinc Oxide/Polyethylene Glycol: Lithium ions) have been synthesized using different molecular weight of polymer. Changing the molecular weight produced no effect of the crystallinity of ZnO nanoparticles if  similar molarity of ethylene glycol unit were used. However, the use of high molecular weight of polymers tended to reduce the size of nanoparticles, which  implied to the enhancement in the luminescence spectra due to increasing  in the particle number concentration. TEM picture of sample prepared using PEG of molecular weight 0f 500,000 exhibitef a particle size of 5 nm, which was close to the value predicted y Waaent-Schere formula or size dependent band gap.Keywords : nanocomposite, luminescent polymer electrolytes, zinc oxide, polyethylene glycol
PROSPEKTIF LEMPUNG ALAM CENGAR SEBAGAI ADSORBEN POLUTAN ANORGANIK DI DALAM AIR: KAJIAN KINETIKA ADSORPSI KATION Co(II) Muhdarina Muhdarina; Abdul Wahab Mohammad; Andanastuti Muchtar
Reaktor Volume 13, Nomor 2, Desember 2010
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (364.858 KB) | DOI: 10.14710/reaktor.13.2.81-88

Abstract

Kemampuan lempung alam Cengar untuk melepaskan kation Co(II) dari air limbah model telah diuji dengan proses adsorpsi. Lempung alam Cengar diimpregnasi dengan larutan garam ammonium 1 molar untuk meningkatkan kemampuan adsorpsinya. Kapasitas adsorpsi kation Co(II) oleh lempung Cengar yang diimpregnasi meningkat di bawah pengaruh waktu kontak dan menurun dengan temperatur. Beberapa model kinetika yaitu order-pertama pseudo, order-kedua pseudo, model Elovich dan difusi intra-partikel telah digunakan untuk mengevaluasi kinetika dan mekanisme interaksi Co(II) pada lempung Cengar. Mekanisme adsorpsi Co(II)-lempung Cengar mengikuti kinetika order-kedua pseudo pada waktu perolehan adsorbat maksimum 120 menit. Dengan model Elovich didapatkan adsorben lempung Cengar memiliki permukaan yang heterogen. Energi aktivasi proses adsorpsi juga dievaluasi di bawah pengaruh temperatur dan didapatkan energi aktivasi yang negatif.
Kinetics and equilibriums adsorption of Cu (II) ion by chitosan and cross-linked chitosan-bentonite Hargono Hargono; Angga Mei Sarah; Feninda Nevrita; Bakti Jos
Reaktor Volume 19 No. 3 September 2019
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (320.152 KB) | DOI: 10.14710/reaktor.19.3.117-124

Abstract

The sorption of Cu (II) particle from aqueous solution onto chitosan and cross-connected chitosan-bentonite (CTS-BTN) as adsorbent were conducted in batch conditions. The impact of different test parameters: starting pH, sorption time was assessed. Equilibrium studies have been completed to decide the limit of chitosan and CTS-BTN for Cu (II) particle. The Langmuir and Freundlich isotherm models were used in the examination of the trial information as linearized conditions. It was discovered that the isotherm information were all around portrayed by the Langmuir isotherm. Chitosan and CTS-BTN showed an adsorption capacity of 125 mg/g and 142.86 mg/g, respectively. The constant of adsorption rate was investigation utilizing a pseudo first order and a pseudo second order model. The pseudo second order model brought about the best fit with test information (R2= 0,991 for CTS and R2= 0,995 for CTS-BTN), additionally giving a constant rate k2, ads= 8.85 x 10-5 g/mg min for CTS and 3.72 x 10-4 g/mg min for CTS-BTN. Recommending that this model could be used in design and applications.Keywords:  adsorption; Cu(II) ion; chitosan; cross-linked; isotherm; kinetics
PERANAN PENGADUKAN TERHADAP KARAKTERISTIK KOMPLEKSASI UREA SEBAGAI SARANA PEMISAHAN ASAM LEMAK OMEGA DARI MINYAK NABATI Dwi Ardiana Setyawardhani; Hary Sulistyo; Wahyudi Budi Sediawan; Mohammad Fahrurrozi
Reaktor Volume 16 No. 2 Juni 2016
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (315.068 KB) | DOI: 10.14710/reaktor.16.2.81-86

Abstract

Modern society concerns more on health, in which natural foods are highly preferred. Poly-Unsaturated Fatty Acids (PUFAs) such as omega 6 and omega 9 are believed to be very important on degeneratif prevention. The PUFAs intake as concentrate is preferred than the one of the whole oil, in order to avoid saturated fatty acids consumption to the human body. Omega 6 and omega 9 fatty acids are mainly content in the vegetable oil. One of the methods of concentrating PUFAs from the oil is urea complexation. For commercial scale, this is very interesting and promising process in Indonesia, which is rich in vegetable oil resources. This method consists of 3 steps : 1) saponification and acidification of the vegetable oil, 2) urea-complexation process and 3) recovery of the PUFAs. The urea-complexation is a separation process based on the molecular size of the aliphatic organic compounds. The objective of the research was to study the effects of mixing time on the crystallization step. This study showed that mixing-time could improve SFA and reduce PUFA in urea inclusion compound, which lead to SFA reduction and PUFA improvement in the concentrate. Mixing also affected the tendency of the fatty acids molecules to form inclusion with urea crystal, and enhanced the substitutions of the guest molecules, especially for polar fatty acids such as MUFA and PUFAs. Keywords : fatty acids, mixing-time, PUFA, urea complexation, vegetable oil. ABSTRAKPentingnya hidup sehat menjadikan konsumsi bahan alami menjadi bagian dari gaya hidup modern. Salah satu nutrisi penting adalah asam lemak tak jenuh ganda (Poly Unsaturated Fatty Acid - PUFA), seperti omega 6 dan omega 9 yang berfungsi untuk mencegah berbagai penyakit degeneratif. Asam lemak omega 6 & 9 banyak terkandung di dalam minyak nabati. Konsumsi dalam bentuk konsentrat asam lemak dinilai lebih efektif karena asam lemak jenuh hanya sedikit yang terikut dalam konsumsi. Salah satu metode pengkonsentrasian PUFA adalah kompleksasi urea. Teknologi pengkonsentrasian PUFA sangat berpotensi untuk dikembangkan di dalam negeri mengingat Indonesia kaya akan sumber minyak nabati. Kompleksasi urea terdiri atas 3 tahapan yaitu 1) tahap penyiapan asam lemak bebas dari minyak nabati, 2) tahap kristalisasi (fraksinasi kompleksasi urea), dan 3) tahap pemungutan asam lemak tak jenuh. Proses ini didasarkan pada pemisahan asam lemak jenuh dan tak jenuh pada minyak nabati berdasarkan perbedaan ukuran diameter molekulnya. Tujuan penelitian ini adalah mempelajari pengaruh waktu pengadukan terhadap komposisi asam lemak melalui proses kompleksasi urea pada minyak nabati. Berdasarkan hasil penelitian ini, adanya pengadukan dapat meningkatkan kadar SFA dan menurunkan PUFA di fraksi kristal, yang berdampak pada penurunan kadar SFA di NUCF dan meningkatkan kadar PUFA di NUCF. Adanya pengadukan juga mempengaruhi tendensi asam lemak untuk masuk ke dalam kristal urea dan mempermudah pergantian guest molecules, khususnya bagi asam lemak polar seperti MUFA dan PUFA.   Kata kunci : PUFA, asam lemak, kompleksasi urea, minyak nabati 
Pemanfaatan Air Asam Tambang Dalam Teknik Elektrokinetik Untuk Menurunkan Kadar Logam Berat Bahan Timbunan Bekas Tambang D. T. Suryaningratyas; F. Firosya; Darmawan darmawan
Reaktor Volume 09 No. 02 Desember 2005
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (5305.271 KB) | DOI: 10.14710/reaktor.9.2.100-106

Abstract

Teknik elektrokinetik merupakan salah satu teknik remediasi tanah atau bahan lain yang terkontaminasi logam berat. Teknik ini dikembangkan terutama untuk mengatasi lokasi-lokasi yang terkontaminasi logam berat dalam level yang cukup tinggi. Prinsip dasar teknik ini adalah dengan memberikan arus searah pada bahan yang terkontaminasi dengan menggunakan elektroda (katoda dan anoda) pada tegangan rendah. Penggunaan air asam tambang (AAT) sebagai larutan elektrolit pada percobaan laboratorium  untuk mengurangi kandungan logam berat pada bahan timbunan bekas tambang telah dilakukan. Penambahan asam cenderung meningkatkan efektivitas teknik ini. Hasil penelitian menunjukkan bahwa teknik elektrokinetik dapat digunakan untuk menurunkan kandungan logam berat (Fe, Cu, Pb, dan Mn) lebih dari 6% sampai 90% dari kandungan semula. Penggunaan air asam tambang sebagai elektrolit tidak menunjukkan hasil yang berbeda nyata dengan penggunaan air sebagai elektrolit. Akan tetapi untuk aplikasi di lapang, pemanfaatan asam tambang yang telah tersedia  di daerah pertambangan akan lebih efisien digunakan dibandingkan dengan menggunakan air bersih.Kata kunci : air asam tambang, kontaminasi, logam berat, remediasi, teknik elektrokinetik
STUDI PENGGUNAAN KATALIS ABU SABUT KELAPA, ABU TANDAN SAWIT DAN K2CO3 UNTUK KONVERSI MINYAK JARAK MENJADI BIODIESEL Husni Husin; Mahidin Mahidin; Marwan Marwan
Reaktor Volume 13, Nomor 4, Desember 2011
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (280.026 KB) | DOI: 10.14710/reaktor.13.4.254-261

Abstract

A STUDY ON THE UTILIZATION OF OIL PALM FIBRE AND FRUIT BUNCH ASH AND K2CO3 FOR CATALYTIC CONVERSION OF JATHROPA OIL TO BIODIESEL. Study on the use of coconut fiber ash, palm bunch ash and K2CO3 as the catalysts for conversion of jatropha oil into biodiesel using methanol solvent has been done. The biodiesel is produced by converting unpurified jatropha oil over catalyst through transesterification reaction. The catalysts are burned at temperature of 500, 600, 800 and 900oC for 10 hours. Transesterification reaction is conducted in three-neck flask at constant temperature of 60oC for 3 hours. The results showed that the unburned and burned coconut fiber ashes at 800oC catalysts give the highest biodiesel yield (87.05 and 87.97%) with low soap content (0.23-0.26%). The characteristic of biodiesel produced over those catalysts met the Indonesian and international quality standards, therefore those catalysts can be used as substitute for K2CO3 commercial catalyst.Abstrak   Studi penggunaan katalis abu sabut kelapa, abu tandan sawit dan K2CO3 untuk konversi minyak jarak menjadi biodiesel dengan pelarut metanol telah dilakukan. Biodiesel dibuat melalui konversi minyak jarak yang belum dimurnikan, menggunakan katalis, melalui reaksi transesterifikasi. Katalis-katalis tersebut dipijarkan pada temperatur 500, 600, 800 dan 900oC selama 10 jam. Reaksi dilangsungkan dalam labu leher tiga pada temperatur konstan 60oC selama 3 jam. Hasil penelitian menunjukkan penggunaan katalis abu sabut kelapa tanpa pemijaran dan dengan pemijaran pada 800oC memberikan perolehan biodiesel tertinggi (87,05 dan 87,97%) dengan kadar sabun rendah (0,23-0,26%). Karakteristik biodiesel yang dihasilkan dari penggunaan katalis-katalis tersebut ini telah sesuai dengan syarat mutu yang ditetapkan oleh Standar Indonesia dan Internasional, sehingga katalis-katalis tersebut layak digunakan sebagai pengganti katalis K2CO3 komersial
HYDROTHERMAL CARBONIZATION OF BIOMASS WASTE BY USING A STIRRED REACTOR: AN INITIAL EXPERIMENTAL RESULTS Herlian Eriska; Kania Dewi; Ari Darmawan Pasek; Enri Damanhuri
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 (293.51 KB) | DOI: 10.14710/reaktor.16.4.212-217

Abstract

Hydrothermal carbonization (HTC) is a thermochemical process used to convert wet biomass waste become a coal-like material with higher carbon content called hydrochar. In this study, design and performance test of hydrothermal carbonization prototype reactor is done. Stirred reactor was made of stainless steel 304 with volume of 1 Liter and electric heater as a heating mantle. The HTC reactor was utilized to perform the carbonization of three materials (paper, left-rice, and woodchip) as substrates, in order to study the influence of the temperature conditions on the hydrochar produced. The substrates represent major component in municpal solid waste (MSW). The study showed that chemical and physical properties of several feedstock and hydrochar varied as a function of reaction temperature. HTC is operated in batch at temperatures of 160°, 190° and 220oC, 60 min of reaction time, and 1 MPa initial pressure of nitrogen gas. Three of product were collected from the process with primary material balance. Results showed the products change as the temperature increased. The results suggested that hydrothermal treatment of biomass waste to solid fuel gave high heating value (HHV) with value of 5231.3, 4569.5, and 5422.7 kcal/kg for paper, left-rice, and woodchip respectively after product dried naturally.
Corrosion Characteristics of Carbon Steel upon Exposure to Biodiesel Synthesized from Used Frying Oil Adhi Setiawan; Nora Amelia Novitrie; Agung Nugroho; W Widiyastuti
Reaktor Volume 17 No. 4 Desember 2017
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1037.72 KB) | DOI: 10.14710/reaktor.17.4.177-184

Abstract

The use of biodiesel leads to corrosion of automotive material, which can potentially shorten engine lifetime. The study aims to investigate the effect of temperature and contact time on the corrosion characteristics of carbon steel upon exposure to biodiesel synthesized from used frying oil. The corrosion rate of carbon steel was analyzed based on weight loss measurement according to the standard of ASTM G31 as affected by temperature and contact time. The immersion temperatures used in this study were 30oC, 40oC, and 70o, respectively. The contact times studied were 30 days, 40 days, and 50 days respectively. The results show that the increase of temperature and contact time of biodiesel on carbon steel surface speeds up the corrosion rate. Maximum corrosion rate (0.083 mmy) was observed on the carbon steel contacted to biodiesel at 70oC for 50 days. The SEM results showed an irregular shape of the corroded carbon steel surface. XRD / FTIR analysis of carbon steel samples show the presence of peaks, detected as Fe2O3, FeO(OH) and Fe2O2CO3, as the corrosion products. Keywords: biodiesel; carbon steel; corrosion; FAME; used frying oil

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