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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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DEALUMINATION AND CHARACTERIZATION OF ZSM - 5 AS CATALYST FOR GLYCEROL CONVERSION TO GLYCEROL MONOLAURATE Didi Dwi Anggoro; Riko Rikardo Putra; Herawati Oktaviani; Lutfi Af’idatul Kamilah; FatmaTsaniya Chamdani
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 (874.364 KB) | DOI: 10.14710/reaktor.18.2.110-116

Abstract

Glycerol Monolaurate (GML) is a naturally occurring fatty acid widely utilized in food, cosmetics, andhomeopathic supplements. Glycerol is a compound glycerides, a byproduct of biodiesel production from the transesterification process. Glycerol is converted to glycerol derivative product that has more value as Glycerol Monolaurate (GML).GML is a naturally occurring fatty acid widely utilized in food, cosmetics, andhomeopathic supplements.One of the catalyst that had beenused is ZSM-5. Dealumination is used to change the acidity of the zeolite. This study consists of several stages, there are dealumination of zeolite ZSM-5 using H2SO4, drying at 110 ° C for 1 hour, Then calcination at a temperature of 550 ° C for 4 hours. Characterization catalyst to testing the acidity of the catalyst by absorption of ammonia and pyridine. Acidity of Zeolite is expressed in the mmol of ammonia or pyridine per gram of catalyst. Synthesis of monolaurate with dealuminated result are performed by GC-MS analysis, it’s to determine the molecular weight and to show a purity of Glycerol Monolaurate. Testing results obtained in the optimum conditions at dealumination temperature and dealumination time respectively are 40-60 0C and 2-5 hours. The dealumination variables are acid concentration, temperature and time of dealumination affecting ZSM-5 acidity and % yield of GML. The acidity affecting the yield% of Glycerol monolaurate produced Keywords :Glycerol, Glycerol Monolaurate, dealumination, ZSM - 5.
PREPARASI KATALIS SILIKA SULFAT DARI ABU SEKAM PADI DAN UJI KATALITIK PADA REAKSI ESTERIFIKASI GLISEROL DENGAN ANHIDRIDA ASAM ASETAT Moh. Noor Salman; Didik Krisdiyanto; K. Khamidinal; Pedy Arsanti
Reaktor Volume 15 No.4 Oktober 2015
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (515.399 KB) | DOI: 10.14710/reaktor.15.4.231-240

Abstract

PREPARATION OF SILICA SULFATE CATALYST FROM RICE HUSK ASH AND CATALYTIC TEST IN GLYCEROL ESTHERIFICATION REACTION WITH ACETIC ACID ANHIDROUS. Synthesis of Silica Sulfate catalyst from rice husk ash and used as catalyst for esterification reaction of glycerol with acetic acid anhydrous has done. Catalyst characterized using Infra-Red Spectrophotometer, X-Ray Diffraction and measurement of surface acidity while reaction product characterized using Gas Chromatography-Mass Spectrometer. Influence of catalyst acidity, reaction time and re-addition of acetic acid anhydrous studied by glycerol conversion and selectivity value of triacetin yielded. Infra-Red spectrophotometer and X-Ray Diffraction analysis of catalyst showed that synthesized catalyst is an amorphous silica sulfate, while esterification analysis using gas chromatography-mass spectrometer showed a triacetin product. Using of silica sulfate catalyst in esterification reaction of glycerol could convert glycerol up to 77% and SS-20 catalyst could give triacetin selectivity value up to 98%. Influence of catalyst acidity doesn’t showed significant influence of glycerol converting value. However, increasing of reaction time could increase glycerol converting and triacetin selectivity. Re-addition of acetic acid anhydrous could increase its selectivity value up to 100%. Keywords: acetic acid anhydrous; glycerol; triacetin Abstrak Silika sulfat telah dibuat dari abu sekam padi dan digunakan sebagai katalis dalam reaksi esterifikasi gliserol dengan anhidrida asam asetat. Katalis dikarakterisasi dengan spektrofotometer infra merah dan difraksi sinar-X sedangkan produk reaksi dikarakterisasi dengan kromatografi gas spektrometri massa. Pengaruh keasaman katalis, waktu reaksi dan penambahan kembali anhidrida asam asetat dipelajari terhadap konversi gliserol dan nilai selektivitas triacetin yang terbentuk. Hasil analisis spektrofotometer infra merah dan difraksi sinar-X terhadap katalis menunjukkan bahwa katalis yang disintesis berupa silika sulfat yang berbentuk amorf, sedangkan hasil analisa terhadap produk esterifikasi menggunakan kromatografi gas spektrometri massa menunjukkan adanya produk triacetin. Penggunaan katalis silika sulfat pada reaksi esterifikasi gliserol dapat mengkonversi gliserol sebesar 77%, dan untuk katalis SS-20 dapat memberikan nilai selektifitas triacetin sebesar 98%. Pengaruh keasaman katalis tidak memberikan pengaruh signifikan terhadap nilai konversi gliserol. Namun semakin lama waktu reaksi nilai konversi gliserol dan selektivitas triasetin meningkat dan penambahan kembali anhidrida asam asetat dapat meningkatkan nilai selektivitas hingga 100%. Kata kunci: anhidrida asam asetat; gliserol; triacetin 
Perbaikan Konversi Reaksi Melalui Peningkatan Transfer Massa Dan Penggunaan Pelarut Fluorinet suprapto suprapto
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 (5467.632 KB) | DOI: 10.14710/reaktor.6.2.85-91

Abstract

Pada penelitian ini, perbaikan konversi reaksi dipelajari dalam sistem reaksi gas-cair oksidasi dimetil benzene. Peningkatan transfer massa dari kedua reaktan dievaluasi kaitannya dengan perbaikan konversi reaksi. Demikian juga penggunaan pelarut organic Fluorinet dipelajari pengaruhnya terhadap peningkatan konversi reaksi. Penelitian secara eksperimental dilakukan di dalam reaktor berpengaduk mekanis pada tekanan atmosferik dan suhu 25 0C untuk oksidasi dimetil benzene (DMB) menggunakan ozon sebagai oksidator. Kedua reaktan gas (DMB dan ozon) dimasukkan secara terpisah dan kontinyu ke dalam reaktor skala laboratorium  berdiameter 100 mm dan tinggi 250 mm. untuk memperoleh peningkatan perpindahan massa, digunakan dua jenis pengaduk berbeda untuk dibandingkan hasilnya terhadap terhadap harga koefisien perpindahan massa dan konversi reaksi, putaran pengaduk dioperasikan dari 0-2000 rpm. Hasil pengamatan menunjukkan bahwa konversi reaksi dapat dinaikkan melalui peningkatan transfer massa. Jika pada saat digunakan  pengaduk 4 blades berdiameter 4 cm diperoleh konversi maksimum sebesar 49%, maka dengan pengaduk 6 blades diameter 6 cm diperoleh konversi lebih tinggi yaitu sebesar 86%. Dalam hal penggunaan pelarut Fluorinet, konversi reaksi meningkat hingga mencapai sebesar 62% sehingga terjadi peningkatan sebesar 24% bila dibandingkan dalam sistem aqueous.Kata kunci : ozon, transfer massa, reaktor berpengaduk, konversi, fluorinet
SINTESIS MEMBRAN ULTRAFILTRASI NON FOULING UNTUK APLIKASI PEMPROSESAN BAHAN PANGAN Luqman Buchori; Heru Susanto; Budiyono Budiyono
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 (963.398 KB) | DOI: 10.14710/reaktor.13.1.10-15

Abstract

Membran ultrafiltrasi (UF) telah terbukti sebagai proses yang menjanjikan untuk aplikasi di bidang pemprosesan bahan pangan. Namun, peristiwa fouling dapat menurunkan kinerja membran secara signifikan. Meskipun banyak metode pengendalian fouling telah diusulkan, dalam banyak kasus kinerja proses sangat dipengaruhi oleh membran sebagai jantung dari proses. Dalam makalah ini pengendalian fouling dilakukan dengan memodifikasi permukaan membran dengan teknik kopolimerisasi foto-grafting. Acrylic acid (AA), acrylamido methylpropane sulfonic acid (AMPS), poly(ethylene glycol) methacrylate (PEGMA), dan N,N-dimethyl-N-(2-methacryloyloxyethyl-N-(3sulfopropyl)ammonium betaine sebagai senyawa zwitterion (ZI) digunakan sebagai monomer fungsional. Pengaruh waktu iradiasi terhadap efektifitas modifikasi telah diamati. Kinerja membran hasil modifikasi kemudian diuji dengan menggunakan berbagai model larutan foulant yang meliputi larutan protein, larutan polisakarida dan larutan polifenol. Hasil penelitian menunjukkan bahwa sifat non fouling membran sangat jelas dapat ditingkatkan baik dengan PEGMA maupun dengan ZI. Secara umum, modifikasi menggunakan PEGMA menunjukkan kinerja yang lebih baik. Larutan polifenol menunjukkan karakter foulant yang paling kuat diantara model foulant.
Nutritional Characteristics and Potential Applications of Flour Prepared from Indonesian Wild White Yam (Dioscorea esculenta L.) Diah Susetyo Retnowati; Ratnawati Ratnawati; Andri Cahyo Kumoro
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 (228.632 KB) | DOI: 10.14710/reaktor.19.2.43-48

Abstract

Gembili or wild white yam (Dioscorea esculenta L.) is one of underutilized tubers that can be found during dry season in Indonesia and other Southeast Asian countries. Although it has been consumed as staple food by people for centuries during famine, no further studies have been conducted to explore its potentials in food applications. This work aims to study the preparation, characterization and potential analysis of Gembili flour for use as raw material in novel foods development. Creamy white flour was obtained from white yam tuber from milling and sieving of dried tuber chips. The flour has water content about 12.08%, which is acceptable for storage. No lipid was detected. In addition, the protein, ash, and fiber content of the flour were respectively 3.00%, 1.27%, and 9.04%. The carbohydrate and amylose contents of the flour were 86.69% and 29.92% indicating its suitability for energy source. As expected, the cyanide content is very low of about 1.688 ppm suggesting that it is safe for consumption. Refer to those properties, Gembili flour can be a promising raw material for the preparation of bakery, cookies, noodle and confectioneries.Keywords: proximate composition, flour, white yam, food, preparation
Hydrothermal liquefaction limbah distilasi bietanol generasi-2 Sabar Pangihutan Simanungkalit; Deini Mansur; Muhammad Arifuddin Fitriady
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 (114.062 KB) | DOI: 10.14710/reaktor.16.2.49-56

Abstract

Dalam penelitian ini dilakukan proses hydrothermal liquefaction limbah distilasi bioetanol generasi-2 dari tandan kosong kelapa sawit. Penelitian difokuskan untuk mengetahui pengaruh parameter-parameter fisik dan kimia terhadap karakteristik produk liquid yang dihasilkan. Untuk parameter fisik yang diamati adalah suhu (250–310°C) dan waktu proses (0-120 menit), sedangkan untuk parameter kimia akan diamati pengaruh penambahan katalis Na2CO3 dan K2CO3 (0-20%). Berdasarkan hasil analisa elemental dan perhitungan nilai kalor, suhu dan waktu proses optimum adalah 270°C dan 30 menit. Penambahan katalis Na2CO3 dan K2CO3 menyebabkan turunnya nilai kalor dari produk liquid dan memperlihatkan pola yang fluktuatif. Sementara itu, senyawa kimia yang terkandung dalam produk liquid berdasarkan hasil analisa GC-MS adalah 2,3-butandiol; asam asetat; aseton; etanol; gliserin; fenol; 2,6-dimetoksi fenol; 2-metoksi fenol dan propilen glikol. Semakin besar konsentrasi katalis Na2CO3 meningkatkan konsentrasi etanol dalam produk liquid, yakni mencapai sekitar 16 mol % Carbon pada 20% Na2CO3. Sedangkan penggunaan katalis K2CO3 tidak memberikan pengaruh yang signifikan.
Halal Perspective of Microbial Bioprocess Based-Food Products Muhamad Kurniadi; Andri Frediansyah
Reaktor Volume 16 No.3 September 2016
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (317.657 KB) | DOI: 10.14710/reaktor.16.3.147-160

Abstract

Halal food industries are growing rapidly in line with the growing number of World’s Muslim populations. The demand of halal food products by the non-Muslim’s countries have also increase as the increasing of the general public understanding of the strickly processed to achive halal status. Halal food is more than just a food product. It is also protect people from poisons, intoxication and hazardous substances exposure. Microbial bioprocess based-food products is one of alternative to create a variety of good quality and nutritious food products. These products can be fermented food, nutraceutical, whole microbes, probiotic and synbiotic. The presence of several microbes in gastric intestinal tract will also maintain mictobiota of human gut. Microbial agent is also important on producing the aroma, taste and color. It is also important on modifiying of food materials. As Muslim, people should follow the halal dietary laws. Halal food means any process to be a food product that is permissible of lawful by Islamic laws. It is defined in the holy Quran and the Sunnah of Prophet Muhammad. In general, the microbial based-food products are categorized into halal, haram and doubtful. To achieve the lawful status, six of main critical points in the use of microbes in food processing need to be considered. Microbial metabolite such as ethanol is one of crucial factor in order to achieve halal status of food products. In order to achieve the global halal market, several strategies must be applied to microbial bioprocess based-food industries.Keywords: microbe, halal, industry, bioprocess, critical point
KARAKTERISTIK FISIS ALUMINOSILIKAT GEOPOLIMER BERBASIS SILIKA SEKAM PADI UNTUK APLIKASI FAST IONIC CONDUCTOR Agus Riyanto; Simon Sembiring; Junaidi Junaidi
Reaktor Volume 17 No. 2 Juni 2017
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (643.572 KB) | DOI: 10.14710/reaktor.17.2.96-103

Abstract

The study aims to investigate the effect of calcination temperatures on the phase formation and electrical properties of aluminosilicate geopolymer prepared from rice husk silica and sodium aluminate. The samples were calcined at temperature from 150 oC to 550 oC, the development of structures was characterized using x-ray difraction (XRD) and the electrical properties were measured by LCR meter. The result obtained indicated the significant role of calcining temperature on phase transformation of boehmite and quartz into aluminosilicate geopolymer, in which at calcining temperatures from 450 oC to 550 oC, and  the samples were dominated by semicrystal to amorphous phase which indicated that the aluminosilicate geoplymer has been formed. The presence of aluminosilicate geopolymer resulted in increased ionic electrical conductivity and dielectric loss factor as well as decrease dielectric constant. Ionic electrical conductivity of the calcined sample at 450 oC is 4,49.10-5 S/cm at frequancy of 5.106 Hz, and XRD analysis demostrated that the main structure is phase of semicrystal aluminosilicate geopolymer. Based on these character, the sample was considered is very suitable used to the fast ionic conductor materials.Studi ini bertujuan untuk menginvestigasi efek suhu kalsinasi pada formasi fasa dan sifat listrik aluminosilikat geopolimer yang dipreparasi dari silika sekam padi dan sodium aluminat. Sampel dikalsinasi pada suhu 150 oC – 550 oC, perubahan struktur dikarakterisasi menggunakan x-ray difraction (XRD) dan sifat listrik diukur menggunakan LCR meter. Hasil yang diperoleh mengindikasikan pengaruh yang signifikan suhu kalsinasi pada transformasi boehmite dan quartz menjadi aluminosilikat geopolimer, dimana pada suhu kalsinasi 450 oC – 550 oC didominasi oleh fasa semikristal hingga amorf yang mencirikan terbetuknya aluminosilikat geopolimer. Terbentuknya struktur aluminosilikat geopolimer diikuti dengan peningkatan konduktivitas listrik ionik, penurunan konstanta dielektrik, serta peningkatan faktor rugi dielektrik. Nilai konduktivitas listrik ionik sampel kalsinasi 450 oC ialah 4,49.10-5 S/cm pada frekuensi 5.106 Hz, dan analisis XRD menunjukkan struktur utamanya berupa fasa semikristal aluminosilikat geopolimer. Berdasarkan karakteristik tersebut, sampel yang ditinjau merupakan material dengan konduktivitas ionik yang tinggi sehingga sampel tersebut sangat potensial untuk dimanfaatkan sebagai fast ionic conductor.
AKTIVITAS INULINASE OLEH Pichia manshurica DAN FUSAN F4 PADA FERMENTASI BATCH DENGAN UMBI DAHLIA (Dahlia sp) SEBAGAI SUBSTRAT Wijanarka Wijanarka; Endang Sutariningsih Soetarto; Kumala Dewi; Ari Indrianto
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 (222.456 KB) | DOI: 10.14710/reaktor.14.3.187-192

Abstract

ACTIVITY OF INULINASE OF Pichia Manshuria AND FUSAN F4 ON BATCH FERMENTATION UDING DAHLIA TUBER (Dahlia sp) AS A SUBSTRATE. A dahlia tuber is one of the common inulin rich crops. Inulin is formed by units of fructans, which are polymers of D-fructose. Inulinases (EC 3.2.1.7) catalyze the hydrolysis of inulin, producing fructooligosaccharides (FOS), inulooligosaccharides (IOS), pulullan, acetone, butanol and sorbitol, therefore dahlia tubers are used as growth media. The inulin hydrolyzing activity has been reported from various microbial strains Pichia manshurica and Fusan F4 which is the result of fusion protoplast. The objective of this study was to determine the activity of inulinase Pichia manshurica and Fusan F4 on the substrate dahlia tubers. Fusan F4 to increase inulinase activity compared with Pichia manshurica and to investigate the kinetics of specific growth rate (μ) and time double (g) from of Pichia manshurica and Fusan F4. The results showed that the exponential phase occurs at 0-12 hour without a lag phase. P. manshurica has a specific growth rate (μ) of 0.18/hour with time double (g) 3.90 hours and the inulinase enzyme activity of 0.56 IU, while for Fusan F4 consecutive has a value μ of 0.20/hour, g of 3.49 hours and the activity of 0.69 IU. The conclusion of this research is to improve Fusan F4 inulinase activity and the ability has to be better than the Pichia manshurica.Umbi dahlia merupakan salah satu umbi yang mengandung inulin. Inulin merupakan polimer fruktan yang dapat dipecah oleh enzim inulinase (E.C. 3.2.1.7) menjadi fruktosa. Fruktosa merupakan bahan baku dasar untuk pembuatan FOS, IOS, pulullan, aseton dan sorbitol, oleh karena itu umbi dahlia digunakan sebagai media pertumbuhan. Enzim inulinase ini secara indigenous dimiliki oleh Pichia manshurica dan Fusan F4 yang merupakan hasil fusi protoplas.Tujuan  penelitian ini adalah  untuk mengetahui aktivitas inulinase Pichia manshurica dan Fusan F4 pada substrat umbi dahlia, Fusan F4 mampu meningkatkan aktivitas inulinase dibandingkan dengan Pichia manshurica serta untuk mengetahui kinetika kecepatan pertumbuhan specifik (µ) dan waktu generasi (g) Pichia manshurica dan Fusan F4. Hasil penelitian menunjukkan bahwa fase  eksponensial terjadi pada jam ke-0 sampai jam ke-12 tanpa diikuti fase lag, Pichia manshurica mempunyai kecepatan pertumbuhan specific (µ)  sebesar 0,18/jam dengan waktu generasi (g) 3,90 jam dan aktivitas enzim inulinase yang dihasilkan sebesar 0,56 IU, sedangkan untuk fusan F4 secara berturut-turut mempunyai nilai µ sebesar 0,20/jam, g sebesar 3,49 jam dan aktivitas sebesar 0,69 IU. Kesimpulan dari penelitian ini adalah Fusan F4 mampu meningkatkan aktivitas inulinase dan mempunyai kemampuan lebih baik dibanding dengan Pichia manshurica.
Elektroplating Tembaga pada Baja Menggunakan Elektrolit Asam Lemah Purwanto Purwanto; Sri Rukiyawati; Aprilina Purbasari
Reaktor Volume 3 No.1 Desember 1999
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (3132.302 KB) | DOI: 10.14710/reaktor.3.1.22-25

Abstract

Elektroplanting tembaga pada besi baja  telah dilakukan dengan menggunakan larutan elektrolit tak beracun asam asetat sebagai pengganti larutan beracun sianida. Variable proses yang dipelajari yaitu perbandingan konsentrasi asam asetat terhadap tembaga sulfat (X1), suhu elektrolit (X2), kerapatan arus katoda (X3), kerapatan arus anoda (X4),  dan jarak anoda-katoda (X5). Percobaan menunjukkan bahwa pemakaian asam asetat  sebagai elektrolit asam lemah menghasilkan endapan yang cemerlangdengan efisiensi arus cukup tinggi berkisar 95%. Variable yang mempunyai efek positif berturut-turut yaitu perbandingan konsentrasi, kerapatan arus katoda, dan kerapatan arus anoda. Sedangkan efek negatif berasal dari pengaruh jarak anoda-katoda dan suhu elektrolit. Pengaruh variabel proses terhadap logam berat yang melapisi katoda (Yd) dan efisiensi arus (η) didekati dengan persamaan linier, dengan kesalahan pendekatan relatif sebesar 20%. Kondisi terbaik ditunjukkan oleh efisiensi arus sebesar 94,5% dan hasil plating yang sangat cemerlang pada X1 = 50 (gr/l) / 100 (gr/l), X2 = 50 0C, X3 = 300 Ampere/m2, X4 = 200 Ampere/m2, dan X5 = 3 cm.

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