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PEMBUATAN SURFAKTAN POLYOXYETHYLENE DARI MINYAK SAWIT: Purwaningtyas, Ery Fatarina; Pramudono, Bambang
Reaktor Volume 12, Nomor 3, Juni 2009
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (902.972 KB) | DOI: 10.14710/reaktor.12.3.175 – 182

Abstract

Minyak sawit masih bisa ditingkatkan nilai tambahnya melalui pengubahan menjadi surfaktan. Surfaktan berbasis minyak nabati bersifat mudah terurai (biodegradable), dan ramah lingkungan. Salah satu surfaktan yang dapat disintesis dari minyak sawit adalah polyoxyethylene mono-digliserid (POE-MDG) melalui proses gliserolisis yang dilanjutkan dengan proses etoksilasi. Tujuan penelitian ini adalah mengkaji parameter proses pada gliserolisis maupun etoksilasi. Proses glyserolisis menggunakan katalis MgO dan pelarut n-butanol, dilakukan dengan memvariasikan suhu, rasio gliserol: minyak, dan rasio n-butanol: minyak. Dari penelitian ini diperoleh variable yang berpengaruh pada proses glyserolisis adalah rasio glyserol: minyak, konversi tertinggi 0,785. Hasil gliserolisis adalah MDG, selanjutnya dietoksilasi untuk mendapatkan surfaktan (POE-MDG). Proses etoksilasi MDG menggunakan katalis MgO, dengan memvariasi perbandingan MDG : polietilen glikol (PEG). Berdasarkan analisa Forrier Transform Infra Red (FTIR) memberikan puncak baru pada 1743,65 cm-1 yang menunjukkan pembentukan ikatan C-O-O. Analisis dengan kolom kromatografi memberikan hasil  polyoxyethylen (POE) tertinggi 9,20 % pada rasio MDG : PEG = 4, waktu reaksi 120 menit, temperatur 1600C, kecepatan pengadukan 400 rpm, konsentrasi katalis 2%. Hasil uji kestabilan emulsi menunjukkan bahwa surfaktan POE-MDG mempunyai efek emulsifier
EKSTRAKSI OLEORESIN DARI KAYU MANIS BERBANTU ULTRASONIK DENGAN MENGGUNAKAN PELARUT ALKOHOL Jos, Bakti; Pramudono, Bambang; Aprianto, Aprianto
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 (65.961 KB) | DOI: 10.14710/reaktor.13.4.231-236

Abstract

ULTRASOUND ASSISTED EXTRACTION OF CINNAMON OLEORESIN FROM CINNAMON BARK USING ALCOHOLS AS SOLVENTS. Cinnamon oleoresin is a complex mixture of resin and essential oil extracted from cinnamon burmanii by using organic solvent, and is primarily used as a coloring and flavoring in food products. Major component in essential oil is cinnamic aldehyde. Extraction was usually performed by percolation or soxhlet with various solvents. Several studies on the extraction of oleoresin have been completed by using polar organic solvents. Generally Recognized as Safe (GRAS) solvents, which are safe to use in food, were considered as alternative extraction solvents. Hildebrand solubility parameter concept was also used to choose the solvent. In this research, oleoresin from cinnamon was extracted by using ultrasound assisted extraction. Methanol, ethanol and isopropyl alcohol were used as the solvent to determine the extraction time, extraction rate and the kinetic model correspond to the yield of oleoresin. The result showed that the optimal time and extraction intensity are 66 minutes and 20% respectively, oleoresin yield by using solvent extraction of methanol, ethanol, and isopropyl alcohol were 22.86%, 17.87%, and 14.64% respectively. The results were similar compared to conventional extraction. Kinetic study confirmed that the second-order kinetic model is suitable for this research and the extraction rate constant for the second-order kinetic model of these solvents were 0.098, 0.057, and 0.089 respectively.  Abstrak  Oleoresin kayu manis merupakan campuran komplek antara resin dan minyak atsiri sebagai hasil ekstraksi kayu manis dengan menggunakan pelarut organik. Oleoresin banyak digunakan sebagai pewarna dan flavor dalam industri makanan. Komponen utama dalam minyak atsiri kayu manis adalah cinnamic aldehyde. Pada umumnya ekstraksi kayu manis menggunakan cara perkolasi atau soxhlet dengan berbagai pelarut. Beberapa studi ekstraksi oleoresin yang telah dilakukan, menunjukkan bahwa penggunaan pelarut polar lebih baik dibandingkan pelarut non polar. Pemilihan pelarut yang digunakan untuk ekstraksi harus mempertimbangkan pelarut GRAS (Generally Recognized as Safe) dan juga parameter kelarutan Hildebrand. Penelitian ini menggunakan metanol, etanol, dan isopropil alkohol sebagai pelarut untuk mengekstraksi oleoresin dari kayu manis yang menggunakan ultrasonik. Tujuan penelitian ini adalah menentukan pengaruh waktu dan intensitas ekstraksi berbantu ultrasonik dan juga menentukan model laju ekstraksi. Hasil penelitian menunjukkan bahwa waktu optimal dan intensitas optimal masing-masing adalah 66 menit dan 20%, sedangkan kadar oleoresin yang dihasilkan dengan pelarut metanol, etanol, dan isopropil alkohol berturut-turut  sebesar 22,86%, 17,87%, dan 14,64%, dimana hasil ini relatif sama dengan hasil ekstraksi dengan menggunakan metode konvensional. Studi kinetika menunjukkan bahwa model laju ekstraksi orde dua lebih sesuai untuk penelitian ini dan dari hasil penelitian diperoleh nilai konstanta laju ekstraksi, k berturut-turut 0,098; 0,057; dan 0,089
POTENTIAL OF LINO3/AL2O3 CATALYST FOR HETEROGENEOUS TRANSESTERIFICATION OF PALM OIL TO BIODIESEL Istadi, Istadi; Pramudono, Bambang; Suherman, S.; Priyanto, Slamet
Bulletin of Chemical Reaction Engineering & Catalysis 2010: BCREC Volume 5 Issue 1 Year 2010 (Scopus Indexed)
Publisher : Department of Chemical Engineering - Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (168.08 KB) | DOI: 10.9767/bcrec.5.1.7128.51-56

Abstract

Production of biodiesel through transesterification process using heterogenous catalysts in order to avoid the saponification problem was studied. In this process, palm oil reacted with methanol to form a mixture of glycerol and biodiese over a solid basic catalyst. One type of the catalysts used in this research is basic catalyst of LiNO3/Al2O3. The parameters studied in this research are concentration of LiNO3 loading on Al2O3 and effect of different reaction time. The products was analyzed using Gas Chromatography to determine composition and yield of resulted methyl esters as well as conversion of palm oil to biodiesel. The major products in this transesterification reaction were biodiesel and glycerol. It can be concluded that the 20 wt% LiNO3/Al2O3 catalyst is potential for producing biodiesel from palm oil over transesterification reaction. Advantages of the usage of this catalyst is that the soap formation was not observed in this research. ©2010 BCREC UNDIP. All rights reserved(Received: 24th April 2010, Revised: 20th May 2010; Accepted: 21st May 2010)[How to Cite: I. Istadi, B. Pramudono, S. Suherman, and S. Priyanto. (2010). Potential of LiNO3/Al2O3 Catalyst for Heterogeneous Transesterification of Palm Oil to Biodiesel. Bulletin of Chemical Reaction Engineering and Catalysis, 5(1): 51-56. doi:10.9767/bcrec.5.1.7128.51-56][How to Link / DOI: http://dx.doi.org/10.9767/bcrec.5.1.7128.51-56 ]
PRODUKSI BIOGAS DARI ECENG GONDOK (EICCHORNIA CRASSIPES) : KAJIAN KONSISTENSI DAN PH TERHADAP BIOGAS DIHASILKAN Yonathan, Arnold; Prasetya, Avianda Rusba; Pramudono, Bambang
JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Volume 1, Nomor 1, Tahun 2012
Publisher : Jurusan Teknik Kimia, Fakultas Teknik, Universitas Diponegoro,

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Abstract

Water hyacinth (Eicchornia crassipes) is one of the weeds type which has the fastest growth amongothers, but it can be used in the biogas production because it contains large number ofhemiselulosa. Anaerobic digestion is a process where the microorganism is doing a biodegradablematerial split within the oxygen devoid. The biogas making process begins at cutting up the waterhyacinth, to be added with the water and to be blended with cow dung later. When the mixedsolution is already well-suited with the operation variable, pour it into the pre-treatmentbiodigester by adding the H2SO4 into the (substrat). The process will present the result atcomposition variable, which is showing the largest biogas production at 2:2,5 composition in1.162,97mL, and the smallest biogas production at 2:1 composition in 12,85mL. The bestcomposition from the fermentation process has done before is used as the dependent variable witha pH variable change. The result shows at the pH interval 4 -7, the biogas production isincreasing, and will decrease at the pH 8. The largest biogas production is at the variable pH 7 inthe amount of 1.162,97mL. The GC analysis result shows the metana that contains inside thebiogas is 0,03mol/100gr water hyacinth.
INOVASI PRODUKSI MINYAK KAYU MANIS DENGAN MENGGUNAKAN TEKNIK HIDRODISTILASI VAKUM Rusliawan, Andita; Wijayanti, Dina Mukti; Pramudono, Bambang
JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Volume 1, Nomor 1, Tahun 2012
Publisher : Jurusan Teknik Kimia, Fakultas Teknik, Universitas Diponegoro,

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Abstract

Cinnamon oil is processed from cinnamon bark that has a high selling price. Cinnamon oil can be produced through a process either distillation or extraction. In this study, cinnamon bark is washed, dried, milled, and sieved to obtain size 2-3; 0.85-2; <0.85 mm. Then vacuum hydrodistillation is carried out with 800mL of water, 100 grams of cinnamon bark, at 70 ° C and 450mmHg (0.59 atm). Product from vacuum hydrodistillation is then measured and analyzed for levels cinnamic aldehyde. Optimum variables in this study are 0.85-2mm particle size and 4.5 hours which give the greatest yield is 3.02 (g oil produced/100 g cinnamon bark). Product of cinnamon oil with vacuum hydrodistillation have a good quality with  72.60% cinnamic aldehyde and fulfilling the standards of cinnamon oil.
PEMBUATAN FILM KOMPOSIT KITOSAN –TAPIOKA : PENGARUH KOMPOSISI TERHADAP KARAKTERISTIK FILM Rokhati, Nur Rokhati; Pramudono, Bambang; Widiasa, I. Nyoman
METANA Vol 9, No 01 (2013): Juli 2013
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (627.628 KB) | DOI: 10.14710/metana.v9i01.7202

Abstract

Abstract Cassava starch can readily be cast into films. However, the cassava starch film is brittle and weak leading to inadequate mechanical properties. Therefore it is necessary blending with other biopolymers that can overcome these drawbacks. In this study, composite film prepared by blending of cassava starch and chitosan solutions with ratio 2:8, 3:7, 4:8, and 5:5. The results show that the mechanical strength of the film increase with increasing the chitosan content. The significant decline in both permeability and degree of swelling with increasing the content of chitosan in the composite film. The hydrophobic acetyl groups of chitosan caused a notable reduction of wettability as well as water permeability. The degree of swelling experiments showed that the films have the highest degree of swelling in water followed by technical ethanol (±95%) and pure analysis ethanol (>99.9%). SEM photographs of the surface of film with the ratio 5:5 have more homogeneous than the ratio 2:8. The amino group peak in IR spectrum of chitosan molecule shifted from 1581 to 1587 cm?1 with the incorporation of starch. These results suggested that these two film-forming components were compatible and an interaction existed between them. Keywords: Chitosan?starch films; composition, characterization
PENINGKATAN YIELD BIODISEL DARI MINYAK BIJI NYAMPLUNG MELALUI TRANSESTERIFIKASI DUA TAHAP Prihanto, Antonius; Pramudono, Bambang; Santosa, Herry
MOMENTUM Vol 9, No 2 (2013)
Publisher : MOMENTUM

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Abstract

Telah  dilakukan  penelitian  tentang  peningkatan  yield  biodisel  dari  minyak  biji  nyamplung melalui  transesterifikasi  dua tahap.  Transesterifikasi  dua  tahap  digunakan  untuk  menggeser reaksi ke arah kanan, sehingga diharapkan dapat meningkatkan yield biodisel. Penelitian ini dilakukan  untuk  mengkaji  pengaruh  rasio  molar  metanol-minyak,  pengaruh  suhu   dan pengaruh  konsentrasi  katalis  terhadap  yield  biodisel  dari  minyak  nyamplung.  Perlakuan pendahuluan  untuk  pemurnian  bahan  baku  yang  dilakukan  meliputi  proses  degumming, esterifikasi  dan  netralisasi.  Transesterifikasi  dua  tahap  dilakukan  dengan  menggunakan variasi rasio molar metanol-minyak (6:1; 7:1; 8:1; 9:1; 10:1), suhu (30 oC, 40 oC, 50 oC, 60 oC, 70 oC) dan konsentrasi katalis KOH (1 %, 1,25 %, 1,5 %, 1,75 %, 2,0 %). Hasil penelitian menunjukkan bahwa rasio molar metanol-minyak, suhu dan konsentrasi katalis berpengaruh terhadap  yield  biodisel.  Pada  rasio  molar  metanol-minyak  8:1,  suhu  60 oC  dan  konsentrasi katalis KOH 1,25  % memberikan yield biodisel maksimal sebesar 92,98  %.  Sebagian besar parameter biodisel dari kondisi terbaik yang diuji telah memenuhi standar  SNI 04-7182-2006. Transesterifikasi  dua  tahap  dapat  meningkatkan  yield  biodisel  dari  minyak  nyamplung, walaupun tidak begitu besar.Kata kunci : yield biodisel, nyamplung (Callophyllum inophyllum), transesterifikasi dua tahap
EKSTRAKSI KONTINYU DENGAN SIMULASI BATCH TIGA TAHAP ALIRAN LAWAN ARAH: PENGAMBILAN MINYAK BIJI ALPUKAT MENGGUNAKAN PELARUT N-HEXANE DAN ISO PROPIL ALKOHOL Pramudono, Bambang; Ardi Widioko, Septian; Rustyawan, Wawan
Reaktor Volume 12, Nomor 1, Juni 2008
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (159.091 KB) | DOI: 10.14710/reaktor.12.1.37-41

Abstract

Tujuan penelitian ini adalah mengkaji rendemen dan selektivitas dari ekstraksi biji alpukat dengan pelarut n-hexane dan isopropyl alcohol (IPA). Ekstraksi dilakukan dengan sistem kontinyu simulasi batch bertahap tiga aliran lawan arah pada temperatur 82 oC (untuk pelarut n- hexane) dan 69 oC (untuk pelarut IPA), selama 2 jam dengan perbandingan bahan dan pelarut sebesar 20 gr/250 gr. Rendemen yang diperoleh pada penggunaan n-hexane dan IPA sebesar 18,69 % dan 17,87 %. Kedua minyak yang dihasilkan baik dari penggunaan n-hexane maupun IPA memenuhi spesifikasi minyak biji alpukat. Dari besarnya rendemen yang diperoleh menunjukkan bahwa secara kuantitatif  pelarut n-hexane lebih baik daripada IPA, tetapi dari segi kualitatif (kandungan impuritas) pelarut IPA lebih baik daripada n-hexane.
Microwave Irradiation-Assisted Chitosan Hydrolysis Using Cellulase Enzyme Rokhati, Nur; Pramudono, Bambang; Istirokhatun, Titik; Susanto, Heru
Bulletin of Chemical Reaction Engineering & Catalysis 2018: BCREC Volume 13 Issue 3 Year 2018 (SCOPUS and Web of Science Indexed, December 2018)
Publisher : Department of Chemical Engineering - Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (493.463 KB) | DOI: 10.9767/bcrec.13.3.2378.466-474

Abstract

The influence of microwave irradiation on the chitosan hydrolysis catalyzed by cellulase enzyme was studied. The hydrolyzed chitosan was characterized by measuring its viscosity and reducing sugar. Further, it was also characterized by Fourier-Transform Infrared Spectroscopy (FT-IR), X-ray Diffraction (XRD), and Scanning Electron Microscope (SEM). The classical Michaelis-Menten kinetic parameters were measured by analyzing the amount of reducing sugars. The results were compared with the hydrolysis by using conventional shaker incubator. The hydrolysis reaction time needed to obtain similar reducing sugar yield was significantly lower for microwave irradiation than shaker incubator. On the other hand, the reduction rate of the relative viscosity was significantly higher for the hydrolysis of chitosan using shaker incubator. A significant difference in chemical structure was observed between hydrolysis using microwave irradiation and shaker incubator. Overall, the result showed that the hydrolysis behavior of chitosan using microwave irradiation is significantly different with using shaker incubator. Copyright © 2018 BCREC Group. All rights reservedReceived: 19th March 2018; Revised: 19th June 2018; Accepted: 25th June 2018How to Cite: Rokhati, N., Pramudono, B., Istirokhatun, T., Susanto, H. (2018). Microwave Irradiation-Assisted Chitosan Hydrolysis Using Cellulase Enzyme. Bulletin of Chemical Reaction Engineering & Catalysis, 13 (3): 466-474 (doi:10.9767/bcrec.13.3.2378.466-474)Permalink/DOI: https://doi.org/10.9767/bcrec.13.3.2378.466-474 
HIDROLISIS ENZIMATIK KITOSAN DENGAN KOMBINASI ENZIM ENDO-GLUCANASE DAN CELLOBIOHYDROLASE Rokhati, Nur; Pramudono, Bambang; Istirokhatun, Titik; Sulchan, Mohammad; Kresnianingrum, Dyah Ayu; Dewi, Luthfi Kurnia
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 (568.317 KB) | DOI: 10.14710/reaktor.15.4.261-267

Abstract

Abstract CHITOSAN ENZYMATIC HYDROLYSIS USING A COMBINATION OF ENDO-GLUCANASE AND CELLOBIOHYDROLASE. Chitosan is very promising in various fields including medicine, pharmacology, and the food industry. However, the application of this polysaccharide is limited by its high molecular weight resulting in its low solubility in aqueous media. In this respect, the chitosan with shorter chain length, display a reduced viscosity and are soluble in aqueous media at pH values close to neutrality. The aim of this study is the hydrolysis of chitosan to obtain a low molecular weight chitosan using enzymes endo-glucanase and cellobiohydrolase. The hydrolysis of chitosan was carried out under a temperature of 40° C and pH 5. Chitosan degradation was monitored by the analysis of reducing sugars and viscosity, whereas the chemical characterization of chitosan is done by using test FTIR (infrared spectroscopy). The results showed that enzyme treatment resulted in a substantial loss in viscosity of the chitosan solution shows depolymerization. Depolymerization using endo-glucanase took place very quickly during the initial 15 minutes. The rate of viscosity decrease on chitosan degradation using cellobiohydrolase is lower than using endo-glucanase. When the reaction time was 4 h, the lowest  viscosity is showed by cellobiohydrolase, and the highest solubility is showed by combination of endo-glucanase and cellobiohydrolase. Keywords: endo-glucanase; cellobiohydrolase; chitosan; hydrolysis Abstrak Kitosan dapat dimanfaatkan di berbagai bidang seperti kedokteran, farmasi dan industri makanan. Aplikasi kitosan sering dibatasi oleh berat molekul kitosan yang tinggi sehingga viskositasnya tinggi dan kelarutannya rendah. Kitosan dengan rantai polimer pendek, akan mempunyai viskositas rendah, dan mudah larut pada larutan/air dengan pH mendekati netral. Penelitian ini bertujuan untuk menghidrolisis kitosan secara enzimatis menggunakan enzim endo-glucanase dan cellobiohydrolase. Hidrolisis kitosan dilakukan pada suhu 40 °C dan pH 5. Degradasi kitosan dipantau melalui analisa gula reduksi dan viskositas, sedangkan karakterisasi kimia kitosan dilakukan dengan menggunakan uji FTIR (infra red spectroscopy). Hasil penelitian menunjukkan bahwa hidrolisis enzimatis kitosan dapat menyebabkan terjadinya penurunan berat molekul yang ditandai dengan adanya penurunan viscositas larutan kitosan. Pada 15 menit awal hidrolisis terjadi penurunan viskositas yang sangat besar. Laju penurunan viskositas enzim cellobiohydrolase lebih rendah dibanding dengan enzime endo-glucanase. Setelah waktu reaksi 4 jam, viskositas terendah diperoleh pada enzime cellobiohydrolase, sedangkan kelarutan tertinggi diperoleh pada kombinasi enzime endo-glucanase dan cellobiohydrolase. Kata kunci: endo-glucanase; cellobiohydrolase; kitosan; hidrolisis