cover
Article Per Year (5 Year)
All
Home Page
OAI Link
Editorial Team
Contact
Reviewer
Google Scholar
Contact Name
Dessy Ariyanti
Contact Email
dessy.ariyanti@che.undip.ac.id
Phone
+62247460058
Journal Mail Official
j.reaktor@che.undip.ac.id
Editorial Address
Department of Chemical Engineering, Diponegoro University Jl. Prof. Soedarto SH Tembalang Semarang 50275
Location
Kota semarang,
Jawa tengah
INDONESIA
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 12 Documents
 1   2 
Search results for , issue "Volume 14, Nomor 1, April 2012" : 12 Documents clear
KARAKTERISTIK INTERAKSI MEMBRAN-FOULANT DAN FOULANT-FOULANT SEBAGAI DASAR PENGENDALIAN FOULING Heru Susanto; Asteria Apriliani Susanto; I Nyoman Widiasa
Reaktor Volume 14, Nomor 1, April 2012
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (205.241 KB) | DOI: 10.14710/reaktor.14.1.17-24

Abstract

THE CHARACTERISTICS OF MEMBRANE-FOULANT AND FOULANT-FOULANT INTERACTIONS AS THE BASIS FOR CONTROL OF FOULING. Industrial membrane applications for solid liquid and liquid-liquid filtration are limited by fouling and concentration polarization. Because fouling significantly reduces the membrane performance and often changes the membrane selectivity, efforts to overcome the fouling problem are very important from practical applications point of view. This paper presents the basic knowledge required to control fouling and recent development in fouling control including the method developed by the author. Control of fouling can be done by (i) commercial membrane modification (post modification) by photo-graft polymerization, (ii) modification by polymer blending during membrane manufacturing and (iii) integration of a pretreatment into membrane processes. The results showed that all the developed methods can significantly reduce the resulting fouling; however, none of the method could totally remove the occurring fouling. The understanding of the membrane-foulant and foulant-foulant interactions is the key to success in control of fouling.Aplikasi teknologi membran untuk pemisahan padat cair di  berbagai industri dibatasi oleh peristiwa fouling yang menyebabkan penurunan laju produk dan perubahan selektifitas membran. Oleh karena itu, pengendalian fouling merupakan upaya yang mutlak harus dilakukan. Makalah ini mempresentasikan pengetahuan dasar yang diperlukan untuk pengendalian fouling dan perkembangan terkini dalam pengendalian fouling termasuk hasil-hasil yang telah dikembangkan oleh penulis. Pengendalian fouling dilakukan dengan (i) modifikasi membran komersial (post modification) menggunakan metode photo-grafting, (ii) modifikasi dengan pencampuran polimer selama proses pembuatan (polymer blend) dan (iii) integrasi unit perlakuan awal (pre-treatment) dengan proses membran. Hasil penelitian menunjukkan bahwa kesemua metode yang dikembangkan dapat mengurangi terjadinya fouling secara signifikan. Namun, tidak ada satu pun metode yang dapat mengurangi fouling dengan sempurna. Pemahaman terhadap interaksi membran-foulant dan foulant-foulant merupakan kunci sukses dalam pengendalian fouling.
PEMANFAATAN KARBON AKTIF ARANG BATUBARA (KAAB) UNTUK MENURUNKAN KADAR ION LOGAM BERAT Cu2+ DAN Ag+ PADA LIMBAH CAIR INDUSTRI Kusmiyati Kusmiyati; Puspita Adi Lystanto; Kunthi Pratiwi
Reaktor Volume 14, Nomor 1, April 2012
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (249.253 KB) | DOI: 10.14710/reaktor.14.1.51-60

Abstract

UTILIZATION OF CHAR COAL ACTIVATED CARBON (CCAB) FOR HEAVY IONS (Cu2+ AND Ag+) REDUCTION FROM INDUSTRIAL WASTE WATER. Industrial wastewater may contain heavy metals such as Cu and Ag those are harmful to the environment if discharged without pretreatment. One of the methods to reduce heavy metals in wastewater is adsorption, to separate certain components from liquid to the surface of solids. Adsorption is a simple method, but most of the adsorbents are expensive, therefore a cheaper adsorbent is required to reduce the cost of the adsorption process. This work utilized bottom ash as an adsorbent. Bottom ash is a waste of combustion products in the coal industry, which contain potentially harmful materials. Activation of bottom ash was made by soaking in peroxide and continuing by heating at a temperature of 500oC. This study was aimed to determine the influence of process parameters (concentration, pH and processing time) to the percentage of amount heavy metals adsorbed, to study the equation isotherm adsorption using Langmuir and Freundlich models, and to calculate the kinetic constants of adsorption based on pseudo -first- order and pseudo-second-order kinetic model. The experiment was conducted in the batch system, where 10 grams bottom ash was mixed with 400 ml of synthetic waste. AAS was used to determine the heavy metals content in the waste solution. The results showed that bottom ash can be used to reduce heavy metals of Cu2+ and Ag+, the optimum condition when the concentration of 25 ppm under acidic conditions, bottom ash was able to adsorb Cu2+ metals ion by 62.79-80.25% at pH 4, and 65.54-85.98% at neutral pH with the same adsorption time of 300 min. For the ion metals Ag+, at acidic solution the metals ion can be adsorbed by 56.51-82.21%, while at neutral pH conditions 59.92-87.55%. Adsorption of bottom ash follows the model of Freundlich isotherm adsorption at acidic and neutral condition, the correlation coefficient (R2)obtained was 0.994 for Cu2+ metals ion and 0.984 for the Ag+ metals ion at acidic solution, whereas 0.986 for Cu2+ metals ion and 9.69 for the Ag+ metals ion at neutral pH. Kinetic model of second order rate describe the adsorption process well at acidic and neutral conditions. At the optimum conditions, the correlation coefficient (R2) of 0.998 for Cu2+ and 0.999 for the Ag+ at acidic solution, whereas 0.993 for Cu2+ and 9.998 for the Ag+ at neutral pH were obtained.  Limbah cair industri bisa mengandung ion logam berat seperti Cu2+ dan Ag+ yang berbahaya bagi lingkungan jika dibuang tanpa melalui pengolahan dahulu. Metode yang digunakan untuk mengurangi ion logam berat dalam limbah cair sudah banyak dilakukan, salah satu diantaranya adalah adsorpsi, yaitu memisahkan komponen tertentu dari fluida ke permukaan zat padat. Adsorpsi merupakan metode yang mudah, akan tetapi kebanyakan adsorben yang digunakan harganya mahal, sehingga perlu adanya alternatif adsorben yang murah. Penelitian ini memanfaatkan karbon aktif arang batubara (KAAB) sebagai adsorbennya. Arang batubara merupakan limbah hasil pembakaran batubara pada industri, yang berpotensi untuk dikembangkan menjadi adsorben, sehingga dapat mengurangi pencemaran lingkungan. Pengaktifan arang batubara dilakukan dengan merendamnya dalam peroxide kemudian dilakukan pemanasan pada suhu 500°C. Penelitian ini bertujuan untuk mengetahui pengaruh parameter proses (konsentrasi, pH dan waktu proses) terhadap persentase ion logam berat teradsorpsi dalam KAAB, mempelajari persamaan kesetimbangan adsorpsi dengan menggunakan model isoterm adsorpsi Langmuir dan Freundlich, dan menghitung konstanta kinetika adsorpsi dengan pendekatan model kinetika pseudo-first-order dan pseudo-second-order. Pelaksanaan penelitian dengan batch, yaitu mengkontakkan 10 gram KAAB dengan 400 ml limbah sintetis. Pengujian kadar ion logam berat menggunakan AAS (Atomic Absorption Spectrophotometer). Hasil penelitian menunjukkan bahwa KAAB dapat digunakan untuk mengurangi kandungan ion logam berat Cu2+ dan Ag+, pada kondisi optimum saat konsentrasi 25 ppm, KAAB mampu mengadsorpsi ion logam Cu2+ sebesar 64,60-88,89% pada pH asam sedangkan pada pH netral sebesar 67,02-80,25%. Untuk ion logam Ag+ pada pH asam mampu mengadsorpsi ion logam sebesar 69,97-82,21%  sedangkan pada kondisi pH netral sebesar 72,71-87,55%. Adsorpsi KAAB mengikuti model Isoterm adsorpsi Freundlich pada pH asam dan netral, koefisien korelasi (R2) 0,994 untuk ion logam Cu2+ dan 0,984 untuk ion logam Ag+saat pH asam, sedangkan pH netral (R2) 0,986 untuk ion logam Cu2+ dan 9,69 untuk ion logam Ag+. Kinetika model second-order rate sesuai untuk proses adsorpsi pH asam dan netral, pada kondisi optimum harga koefisien korelasi (R2) >  0,998.
PENGARUH STRUKTUR PORI TERHADAP KAPASITANSI ELEKTRODA SUPERKAPASITOR YANG DIBUAT DARI KARBON NANOPORI Teguh Ariyanto; Imam Prasetyo; Rochmadi Rochmadi
Reaktor Volume 14, Nomor 1, April 2012
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (794.377 KB) | DOI: 10.14710/reaktor.14.1.25-32

Abstract

THE EFFECT OF PORE STRUCTURE ON THE ELECTRODE CAPACITANCE OF SUPERCAPACITOR PREPARED BY NANOPOROUS CARBON. Nanoporous carbons, due to high specific surface area, high pore accessibility, and relatively low cost, have been used as material electrode supercapacitors. In this work, the influence of pore structure of nanoporous carbons on the specific capacitance of supercapacitors was examined. Nanoporous carbons with several types of pore structure were prepared by carbonization of phenolic resin produced by polymeric condensation of phenolic compound with formaldehyde. Furthermore, ethylene glycol, as a filler, was added in the phenolic resin polymerization to increase the mesoporosity of nanoporous carbon. The nanoporous carbons produced were characterized for their surface morphology, specific internal surface area (BET method), and pore structure. Samples were used as electrode material in supercapacitor and specific capacitances were characterized by galvanostatic test using 30% KOH aqueous solution as electrolyte. The capacitance test of supercapacitors exhibited that increasing mesoporosity increase specific capacitance value of supercapacitors. The highest specific capacitance of 336 F/g was obtained by using mesoporous carbon produced by carbonization of resorcinol phenol formaldehyde ethylene glycol (C-RPFEG2) as electrode material of supercapacitors.  Karbon nanopori dikarenakan memiliki luas permukaan internal yang tinggi, aksesibilitas pori yang baik, dan relatif murah telah digunakan sebagai material elektroda superkapasitor. Pada penelitian ini, pengaruh struktur pori dari karbon nanopori terhadap kapasitansi spesifik superkapasitor telah dipelajari. Karbon berpori dengan berbagai struktur pori dibuat dengan cara karbonisasi phenolic resin yang dibuat dengan cara polimerisaasi kondensasi senyawa phenolic dengan formaldehyde. Selain itu, etilen glikol sebagai filler ditambahkan pada saat polimerisasi phenolic resin untuk meningkatkan mesoporositas dari karbon nanopori. Karbon yang diperoleh dikarakterisasi berupa morfologi permukaan, luas permukaan spesifik (metode BET), dan struktur pori. Karbon tersebut kemudian digunakan sebagai material elektroda superkapasitor dan kapasitansi spesifik dikarakterisasi dengan tes galvanostatik menggunakan KOH 30% sebagai elektrolit. Uji kapasitansi superkapasitor menunjukkan bahwa meningkatnya mesoporositas karbon nanopori akan meningkatkan nilai kapasitansi spesifik. Kapasitansi spesifik tertinggi sebesar 336 F/g diperoleh jika menggunakan karbon mesopori hasil karbonisasi resorcinol phenol formaldehyde ethylene glycol (C-RPFEG2) sebagai material elektroda superkapasitor.
SINTESIS SENYAWA C18H26O9 DARI HIPTOLIDA HASIL ISOLASI DAUN HYPTIS PECTINATA Meiny Suzery; Ely Kusniawati; Dwi Hudiyanti; Bambang Cahyono
Reaktor Volume 14, Nomor 1, April 2012
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (230.961 KB) | DOI: 10.14710/reaktor.14.1.68-72

Abstract

SYNTHESIS OF C18H26O9 COMPOUNDS FROM HYPTOLIDE ISOLATED FROM HYPTIS PECTINATA LEAVES. Isolation of hyptolide has been done from Hyptis pectinata, and alkene group transformation through oxidation reactions using H3B: OEt2 to the isolated compound was also conducted. Product analyses were carried out using TLC, UV spectrometry, IR, and LC-MS. Pure crystal with melting point of 86-87oC was isolated. The yield was 1.75% (w/w). After analysing and compilating of spectroscopic data it was confirmed as hyptolide compound. Hydroboration of this compound (followed by hydrolysis using H2O2 under alkaline conditions) produce its alcohol derivatives, with 28.9% the percentage of transformation, it was demonstrated by LCMS data. IR spectrum at 3600cm-1, confirming the replacement of hydroxyl bond by alkene. Regioselectivity of addition reaction is proposed through simulation with Chem Office. The reaction product was suspected as 6-hydroxy-7-(6-oxo-3,6-dihydro-2H-pyran-2-yl) heptane-2,3,5-tryil triacetate. Extension of reaction time to 24 hours, has increase hydroboration product to 78.3%. This research has opened other studies of natural materials in accordance to the roadmap set.  Telah dilakukan isolasi hiptolida dari bahan alam Hyptis pectinata, dan transformasinya melalui reaksi oksidasi menggunakan H3B:OEt2 terhadap gugus alkena pada senyawa hasil isolasi. Analisis produk dilakukan menggunakan KLT, spektrometri UV, IR, dan LC-MS. Kristal murni dengan titik leleh 86-87oC berhasil diisolasi dengan rendemen 1,75 % (b/b), dirujuk sebagai senyawa hiptolida setelah melalui analisis dan kompilasi data-data spektroskopi. Hidroborasi terhadap senyawa hiptolida (yang diikuti hidrolisis menggunakan H2O2 dalam suasana basa) menghasilkan senyawa alkohol turunannya, dengan persentase transformasi sebesar 28,9%, dapat ditunjukkan melalui data LCMS. Data spectrum IR menunjukkan adanya puncak pada 3600cm-1, memperkuat dugaan  adanya ikatan hidroksil menggantikan gugus alkena. Regioselektivitas reaksi adisi diusulkan melalui simulasi dengan Chem Office, produk reaksi diduga mempunyai struktur  sebagai 6-hydroxy-7-(6-oxo-3,6-dihydro-2H-pyran-2-yl)heptane-2,3,5-tryil triacetate. Perpanjangan waktu reaksi selama 24 jam, telah dapat menaikkan produk hidroborasi menjadi 78,3%. Data penelitian ini telah membuka jalan bagi penelitian-penelitian bahan alam lain sesuai dengan roadmap penelitian yang telah ditetapkan.
KARAKTERISASI PROSES PENGERINGAN JAGUNG DENGAN METODE MIXED-ADSORPTION DRYING MENGGUNAKAN ZEOLITE PADA UNGGUN TERFLUIDISASI Hargono Hargono; Mohamad Djaeni; Luqman Buchori
Reaktor Volume 14, Nomor 1, April 2012
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (322.265 KB) | DOI: 10.14710/reaktor.14.1.33-38

Abstract

CHARACTERIZATION OF CORN DRYING PROCESS USING MIXED-ADSORPTION DRYING METHOD UTILIZING ZEOLITE PARTICLES IN A FLUIDIZED BED SYSTEM. Corn (Zea mays L.) representing important food requirement besides paddy and wheat. Handling of time after rice harvest become the priority so that corn quality can be awaked better. Drying process by adsorption-fluidized bed become a choice to replace the conventional corn drying systems. This research aim to look for the effect of the inlet air temperature, type of zeolite, and ratio of corn and zeolite to drying rate, content of protein and fat, and to calculate dying rate constant, k. Energy efficiency is calculated based on amount of heat is used to evaporate the water from corn (Qevap) divided by total of heat requirement for the regeneration of zeolite and increase the air temperature (Qintr). This research conducted by mixing zeolite as adsorben with the corn with the certain comparison ratio in the fluidized bed at temperature of 30-50oC. Results of research indicate that the fastest drying rate is marked by biggest water rate degradation that happened at 50oC by zeolite sintetis and ratio of corn and zeolite is 25:75%. Drying rate constant is 0.0303. Protein content degradates from 9.10% to 8.30%, while for the content of fat is constant. Energy efficiency is obtained of 81.23%. Jagung (Zea mays L.) merupakan kebutuhan pangan yang penting selain padi dan gandum sehingga penanganan paska panen menjadi prioritas agar kualitas jagung dapat terjaga dengan baik. Proses pengeringan dengan cara adsorpsi-unggun terfluidisasi menjadi suatu pilihan untuk menggantikan sistim pengering jagung konvensional yang boros energi. Penelitian ini bertujuan untuk mencari pengaruh suhu udara masuk, jenis zeolite, dan rasio berat jagung dan zeolite terhadap kecepatan pengeringan, kandungan protein dan lemak dan menghitung harga konstanta laju pengeringan, k. Untuk keperluan energi dihitung pula efisiensi energi (h) berdasarkan jumlah panas yang digunakan untuk menguapkan air dari jagung (Qevap) dibagi dengan kebutuhan panas total untuk meregenerasi zeolite dan menaikkan suhu udara (Qintr). Penelitian dilakukan dengan mencampurkan zeolite sebagai adsorben dengan jagung dengan rasio perbandingan tertentu dalam suatu unggun yang difluidisasi menggunakan udara pada suhu percobaan 30-50oC. Hasil penelitian menunjukkan bahwa laju pengeringan paling cepat ditandai oleh penurunan kadar air yang paling besar yang terjadi pada suhu 50oC dengan menggunakan zeolite sintetis dan dengan rasio berat jagung dan zeolite adalah 25% : 75%. Nilai konstanta laju pengeringan diperoleh 0,0303. Kadar protein terjadi penurunan dari 9,10% menjadi 8,30%, sedangkan untuk kandungan lemaknya relatif tetap. Hasil perhitungan diperoleh efisiensi energi (h) sebesar 81,23%.
MODEL KINETIKA REAKSI PEMBENTUKAN POLYOL BERBASIS MINYAK SAWIT La Ifa; Sumarno Sumarno; Susianto Susianto; Mahfud Mahfud
Reaktor Volume 14, Nomor 1, April 2012
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (115.839 KB) | DOI: 10.14710/reaktor.14.1.1-8

Abstract

REACTION KINETIC MODEL OF RBD PALM OIL BASED-POLYOL PRODUCTION. Polyol, a raw material of polyurethane, has successfully been produced from a renewable resource namely RBD palm oil. This polyol was made by firstly adding a peroxyacetic acid formed in situ from H2O2 and CH3COOH with H2SO4 as cataliyst into RBD palm oil to form epoxidized RBD palm oil. The epoxidized palm oil then was added to a mixture of methanol (MeOH), isopropanol (IPA), and H2SO4 for 2 hours at 60oC so that palm oil-based polyol was formed. The main equipment used in this research was a 500 mL three necked flask, equipped with a reflux condeser, thermometer, water bath and magnetic stirrer. The product was analysed using a titration method and Infra Red (IR) Spectroscopy. It was obtained that the produced palm oil-based polyol has a value of hydroxyl number of 150-209 mg KOH/g sample and a viscosity of 740.777 cP. These results are in accordance with other polyol products from other sources. The kinetic of palm oil-based kinetic was studied and the best model of the reaction rate equation was where k’ = 3.399 e-2391.,6/RT.  The unit of  k is L2 mol-2 menit-1 . The average error of the equation is 4,549%.  Polyol, bahan baku polyuretan, telah berhasil dibuat dari bahan baku terbarukan yakni polyol berbasis RBD palm olein. Polyol ini mula-mula dibuat dengan menambahkan asam peroksi asetat yang dibentuk secara in situ dari H2O2 dan CH3COOH dengan katalis H2SO4 kedalam RBD palm olein untuk membentuk RBD palm olein terepoksidasi. RBD palm oil terepoksidasi ditambahkan kedalam campuran metanol (MeOH), isopropanol (IPA) dan sejumlah katalis H2SO4 selama 2 jam pada suhu 60 oC sehingga terbentuk polyol berbasis RBD palm oil. Peralatan utama yang digunakan dalam percobaan pembuatan polyol adalah labu leher tiga 500 mL dilengakapi dengan kondesor reflux, termometer, water bath dan magnetic stirrer. Polyol produk dianalisa bilangan hidroksil dengan cara titrasi dan dianalisis dengan Infra Red (IR) Spectroscopy. Polyol berbasis RBD palm oil yang dihasilkan memiliki bilangan hidroksil 150-209 mg KOH/g sampel dan viskositas 740,777 cP. hasil ini sebanding dengan polyol yang dihasilkan dari sumber minyak yang lain. Kinetika reaksi polyol berbasis RBD palm oil telah dipelajari dan hasil terbaik didekati dengan persamaan laju reaksi yang diperoleh pada penelitian adalah dimana k’ = 3,399 e-23913,6/RT dalam satuan L2 mol-2 menit-1. Kesalahan estimasi rata-rata adalah 4,549%. Kata kunci: model kinetika; RBD palm oil; polyol
EKSTRAKSI TANNIN SEBAGAI BAHAN PEWARNA ALAMI DARI TANAMAN PUTRIMALU (MIMOSA PUDICA) MENGGUNAKAN PELARUT ORGANIK Tjukup Marnoto; Gogot Haryono; Dewi Gustinah; Fendy Artha Putra
Reaktor Volume 14, Nomor 1, April 2012
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (208.452 KB) | DOI: 10.14710/reaktor.14.1.39-45

Abstract

EXTRACTION OF TANNINS AS NATURAL DYES FROM PUTRIMALU (MIMOSA PUDICA) PLANT USING VARIOUS ORGANIC SOLVENTS. Public awareness on using natural dyes has encouraged the extraction of tannins from putrimalu. Extraction was performed continuously using a Soxhlet apparatus. The parameter studied was the influence of solvent polarity on the amount of tannin and mass transfer coefficient. Tannin was extracted from ten grams of dried putrimalu plants using polar solvents (ethanol, acetone and methanol) and a non-polar solvent (n-hexane). Extraction is considered complete when the concentration of tannins in the liquid is no longer changing with time. Liquid samples were withdrawn every 20 minutes interval for tannin analyses using Thin Layer Chromatography (TLC). The results showed that the maximum concentration of tannins in the extract (g/mL) when extraction were performed using n-hexane was 0.0031, acetone (0.016), methanol (0.0274) and ethanol (0.044). From extract yield and mass transfer coefficient point of views, it can be concluded that the best solvent is ethanol. The relationship between tannin concentration in the ethanol 96% solvent and the time was expressed in term of mathematical equations             CAL=1.046(1-e-0.0213t) with error was 3.6%. Where CAL is the concentration of tannins in the solvent (g/ml) and t is the extraction time (minutes).  Kesadaran masyarakat untuk kembali menggunakan bahan pewarna alami mendorong dilakukannya ekstraksi tannin dari putrimalu. Ekstraksi dilakukan secara kontinyu menggunakan alat Soxhlet. Parameter yang dipelajari adalah pengaruh polaritas pelarut terhadap ekstrak tannin dan koefisien transfer massa. Tannin diekstrak dari sepuluh gram tanaman putrimalu kering menggunakan pelarut polar (etanol, aseton dan metanol) dan pelarut non-polar n-heksana. Ekstraksi dianggap selesai jika konsentrasi tannin di dalam pelarut sudah tidak berubah. Tannin di dalam contoh cairan yang diambil setiap selang waktu 20 menit  dianalisis menggunakan Thin Layer Chromatography (TLC). Hasil penelitian menunjukkan bahwa konsentrasi tannin maksimum (g/mL) yang terdapat dalam larutan yang mengandung ekstrak jika ekstraksi menggunakan n-heksana adalah 0,0031, aseton (0,016), metanol (0,0274) dan etanol (0,044). Hasil penelitian menunjukkan bahwa ditinjau dari perolehan ekstrak dan koefieisen perpindahan massa, maka pelarut yang terbaik adalah etanol. Hubungan antara konsentrasi tannin di dalam pelarut etanol 96% dan waktu dinyatakan dengan persamaan matematika: CAL=1,046(1-e-0,0213.t) dengan kesalahan 3,6%. Dimana CAL adalah konsentrasi tannin dalam pelarut (g/mL) dan t adalah waktu ekstraksi (menit)
STUDI METODE-METODE EKSTRAKSI PEWARNA MAKANAN ALAMI ANNATTO DARI BIJI KESUMBA (Bixa orellana) Johnner Parningotan Sitompul; Martha Situ Situmorang; Tatang Hernas Soerawidjaja
Reaktor Volume 14, Nomor 1, April 2012
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (309.15 KB) | DOI: 10.14710/reaktor.14.1.73-78

Abstract

Annatto is natural food colorant extracted from Bixa orellana seeds. The main constituent of annatto is bixin, a carotenoid having carboxylic acid groups at both ends of its molecular chain and one of these is methyl-esterified. The carboxylic acid groups of bixin and norbixin cause the molecule to dissolve in aqueous bases. The methyl ester structure causes the molecule dissolving in oil and other organic solvents. The double bond conjugated chain causes bixin dissolved in most organic solvents. These characteristics are mainly bases for extraction solvent selection. The objectives of this research are to evaluate the performance of ethyl acetate and acetone as solvents for annatto extraction with different method of extraction and to obtain a procedure for preparing general purpose annatto extract having the highest possible of bixin yield. Two methods of extraction are carried out using Soxhlet method (at solvent boiling temperature) and ultrasonic bath extraction at room temperature. The selected solvents are ethyl acetate and acetone that have medium polarity index and low boiling point. The bixin quality is examined by measuring pigment content with spectrophotometer at certain wavelength. Two types of seeds from different places in Indonesia will be the investigated as sources of annatto. Experimental results for extraction with Soxhlet method shows that yield of bixin (upon seed) from ultrasonic bath extraction is higher that is 0.584% (w), compared to Soxhlet extraction 0.443% (w). For ultrasonic bath extraction, yield of bixin (upon seed) with ethyl acetate as solvent is 0.602%, much higher compared to that from acetone 0.565%. Extraction with Soxhlet method gives different results. Yield of bixin (upon seed) with acetone as solvent is higher which is 0.460%, compared to ethyl acetate which is 0.427%. Seeds from Bandung (West Java) and Duri (Riau) do not give significant difference of bixin yield from two methods of extraction. Annatto merupakan pewarna alami makanan yang didapatkan melalui ekstraksi dari biji pohon kasumba (Bixa orellana) dengan komponen pewarna utamanya adalah bixin. Keberadaan ikatan rangkap terkonjugasi menyebabkan bixin dan norbixin  larut dalam sebagian besar pelarut organik. Ciri struktur kimia dari bixin ini yang menjadi dasar dalam pemilihan pelarut untuk ekstraksi pewarna annatto. Tujuan makalah ini adalah studi metode-metode ekstraksi terhadap perolehan bixin, metode Soxhlet pada temperatur didih pelarut dan metoda ultrasonic bath pada temperatur kamar, dengan dua tempat sumber biji kasumba, Bandung dan Duri. Pelarut yang digunakan adalah etil asetat dan aseton. Pengujian dilakukan dengan mengukur kadar pigmen yang dihasilkan menggunakan spektrofotometri pada panjang gelombang tertentu. Dari penelitian ini, didapatkan data yield (perolehan bixin) dari berbagai variasi percobaan. Perolehan bixin (terhadap biji) yang didapat dari ekstraksi ultrasonic bath lebih tinggi yaitu rata-rata sebesar 0,584%, dibanding dengan metode soxhlet yang rata-rata sebesar 0,443%. Ekstraksi menggunakan metode ekstraksi ultrasonic bath, dan menggunakan pelarut etil asetat lebih tinggi yaitu rata-rata 0,602% daripada menggunakan aseton yang rata-rata 0,565%. Sedangkan dengan metode soxhlet menunjukkan perolehan bixin berbeda, dengan pelarut aseton 0,460%, sedangkan untuk pelarut etil asetat adalah 0,427%. Biji yang berasal dari 2 tempat berbeda, ketika diekstraksi dengan dua metode tersebut tidak memberikan perbedaaan hasil bixin yang signifikan
THE BEHAVIOR OF SOLUBLE METALS ELUTED FROM Ni/Fe-BASED ALLOY REACTORS AFTER HIGH-TEMPERATURE AND HIGH-PRESSURE WATER PROCESS M. Faisal; Hiroyuki Daimon; Koichi Fujie
Reaktor Volume 14, Nomor 1, April 2012
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (228.988 KB) | DOI: 10.14710/reaktor.14.1.9-16

Abstract

The behavior of heavy metals eluted from the wall of Ni/Fe-based alloy reactors after high-temperature and high-pressure water reaction were studied at temperatures ranging from 250 to 400oC. For this purpose, water and cysteic acid were heated in two reactor materials which are SUS 316 and Inconel 625. Under the tested conditions, the erratic behaviors of soluble metals eluted from the wall of Ni/Fe-based alloy in high temperature water were observed. Results showed that metals could be eluted even at a short contact time. The presence of air also promotes elution at sub-critical conditions. At sub-critical conditions, a significant amount of Cr was extracted from SUS 316, while only traces of Ni, Fe, Mo and Mn were eluted. In contrast, Ni was removed in significant amounts compared to Cr when Inconel 625 was tested. It was observed that eluted metals tend to increased under acidic conditions and most of those metals were over the limit of WHO guideline for drinking water. The results are significant both on the viewpoint of environmental regulation on disposal of wastes containing heavy metals, toxicity of resulting product and catalytic effect on a particular reaction.
MANNAN PRECIPITATION FROM ALOE VERA LEAF PULP JUICE USING METHANOL AND ISOPROPYL ALCOHOL AS ANTI-SOLVENT: EXPERIMENTAL AND EMPIRICAL MODELLING APPROACH Diah Susetyo Retnowati; Andri Cahyo Kumoro
Reaktor Volume 14, Nomor 1, April 2012
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (74.848 KB) | DOI: 10.14710/reaktor.14.1.46-50

Abstract

Precipitation of mannan from Aloe vera leaf pulp juice was investigated using anti-solvent precipitation process under room temperature condition. The aims of this work were to study the effects of types (methanol and isopropyl alcohol) and amount of anti-solvent on the precipitation phenomena and to propose a simple mathematics model for evaluating the precipitation rate of mannan (Rβ). The experiments were carried out using a semi batch system; where continuous drop wise addition of anti-solvent to the Aloe vera leaf pulp juice was kept constant at 50.4 mL/min, while the speed of stirring was maintained at 675 rpm. At every run of the experiments, the time at which the precipitation began was recorded and the experiment was terminated when no further precipitation occurred. The samples were withdrawn from the system at every 25 min after the first precipitation for mannan analysis. The results of this work showed that isopropyl alcohol acted as a more effective anti-solvent to precipitate mannan from Aloe vera leaf pulp juice than methanol. The mathematics model represented the precipitation phenomena fairly well with average relative deviation only 11.73%, and finally suggested that the precipitation rate obeyed the zero order.  PENGENDAPAN MANNAN DARI JUS DAGING DAUN LIDAH BUAYA (ALOE VERA) MENGGUNAKAN METANOL DAN ISOPROPIL ALKOHOL SEBAGAI ANTI SOLVEN: PERCOBAAN DAN PEMODELAN DENGAN PENDEKATAN EMPIRIK. Pengendapan mannan dari jus daun lidah buaya (Aloe vera) dengan teknik pengendapan menggunakan anti-pelarut dikaji pada suhu kamar. Tujuan dari penelitian ini adalah untuk mempelajari pengaruh jenis anti-pelarut (metanol dan isopropil alkohol) dan massa anti-pelarut terhadap fenomena pengendapan mannan, serta mengembangkan model matematik dengan pendekatan empiric untuk mengevaluasi laju pengendapan mannan (Rβ). Percobaan dilakukan dalam sistem yang bekerja secara semi-batch, dengan anti-pelarut diumpankan secara terus menerus dalam bentuk tetesan-tetesan dengan laju 50,4 mL/men dan pengadukan dijaga tetap pada 675 putaran per menit (ppm). Pada setiap percobaan, waktu yang diperlukan sejak pengumpanan anti-pelarut hingga saat endapan pertama kali terbentuk dicatat, dan percobaan dihentikan jika tidak ada lagi endapan yang terbentuk. Cuplikan cairan diambil setiap 25 menit sejak endapan pertama terbentuk dan dianalisis kandungan mannannya. Hasil penelitian menunjukkan bahwa isopropil alkohol merupakan anti-pelarut yang lebih efisien dibandingkan dengan metanol untuk mengendapkan mannan dari jus daun lidah buaya. Dari pemodelan matematik diketahui bahwa laju pengendapan mannan mengikuti order nol. Model matematik yang diusulkan dapat mewakili fenomena pengendapan mannan dengan baik yang ditunjukkan dengan ralat rata-rata sebesar 11,73%.

Page 1 of 2 | Total Record : 12

 1   2 

Filter by Year

2012 2012


Reset
Filter By Issues
All Issue Volume 25 No.1 April 2025 2025: Just Accepted and Article in Press Volume 24 No.3 December 2024 Volume 24 No.2 August 2024 Volume 24 No.1 April 2024 Volume 23 No.3 December 2023 Volume 23 No.2 August 2023 Volume 23 No.1 April 2023 Volume 22 No. 3 December 2022 Volume 22 No.2 August 2022 Volume 22 No. 1 April 2022 Volume 21 No.4 December 2021 Volume 21 No. 3 September 2021 Volume 21 No. 2 June 2021 Volume 21 No. 1 March 2021 Volume 20 No.4 December 2020 Volume 20 No.3 September 2020 Volume 20 No.2 June 2020 Volume 20 No.1 March 2020 Volume 19 No. 4 December 2019 Volume 19 No. 3 September 2019 Volume 19 No. 2 June 2019 Volume 19 No. 1 March 2019 Volume 18 No. 4 December 2018 Volume 18 No. 3 September 2018 Volume 18 No. 2 June 2018 Volume 18 No. 1 March 2018 Volume 17 No. 4 Desember 2017 Volume 17 No. 3 September 2017 Volume 17 No. 2 Juni 2017 Volume 17 No.1 Maret 2017 Volume 16 No.4 Desember 2016 Volume 16 No.3 September 2016 Volume 16 No. 2 Juni 2016 Volume 16 No.1 Maret 2016 Volume 15 No.4 Oktober 2015 Volume 15 No.3 April 2015 Volume 15, No.2, OKTOBER 2014 Volume 15, No.1, APRIL 2014 Volume 14, No. 4, OKTOBER 2013 Volume 14, No. 3, APRIL 2013 Volume 14, Nomor 2, Oktober 2012 Volume 14, Nomor 1, April 2012 Volume 13, Nomor 4, Desember 2011 Volume 13, Nomor 3, Juni 2011 Volume 13, Nomor 2, Desember 2010 Volume 13, Nomor 1, Juni 2010 Volume 12, Nomor 4, Desember 2009 Volume 12, Nomor 3, Juni 2009 Volume 12, Nomor 2, Desember 2008 Volume 12, Nomor 1, Juni 2008 Volume 11, Nomor 2, Desember 2007 Volume 11, Nomor 1, Juni 2007 Volume 10, Nomor 2, Desember 2006 Volume 10 No. 1 Juni 2006 Volume 09 No. 02 Desember 2005 Volume 09 No.1 Juni 2005 Volume 08 No.2 Desember 2004 Volume 08 No.1 Juni 2004 Volume 07 No.2 Desember 2003 Volume 07 No. 1 Juni 2003 Volume 6 No. 2 Desember 2002 Volume 6 No. 1 Juni 2002 Volume 5 No.2 Desember 2001 Volume 5 No. 1 Juni 2001 Volume 3 No.1 Desember 1999 More Issue