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PEMBUATAN BIOETANOL DARI PATI UMBI KIMPUL (Xanthasoma Sagittifolium ) Sukaryo Sukaryo; Bakti Jos; Hargono Hargono
JURNAL ILMIAH MOMENTUM Vol 9, No 2 (2013)
Publisher : Universitas Wahid Hasyim

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.36499/jim.v9i2.921

Abstract

Bioetanol  merupakan  energi  terbaharukan  yang  dapat  mengatasi  krisis  energi  yang disebabkan  berkurangnya  energi  yang  berbasis  fosil.  Produksi  bietanol  umumnya menggunakan  bahan  yang  mengandung  karbohidrat  sebagai  bahan  baku  umumnya  yang digunakan  sumber  makanan  pokok  pengganti  beras    misalnya  ketela.  Salah  satu  alternative bahan  baku  yang  tidak  mempengaruhi  sumber  makanan  pokok  adalah  umbi  kimpul  ( Xanthasoma sagittifolium .). Umbi kimpul kandungan karbohidratnya sekitar  34,2 gr per 100 gr  berat  bahan   Proses  yang  umum  digunakan  adalah  fermentasi.  Diharapkan  perolehan alkohol lebih banyak dengan memvariasikan waktu fermentasi ( 1, 3, 5, 7 dan 9 ) hari ,  jumlah enzim α-amilase ( 1; 1,5; 2; 2,5; dan 3 ) dan glukoamilase yang ditambahkan ( 1; 1,5; 2; 2,5; 3 ).  Proses  ini  terdiri  tiga  tahap  yaitu  likuifikasi,  sakarifikasi  dan  fermentasi.  B ioetanol  yang diperoleh kadarnya  9 % dalam waktu fermentasi  7 hari. Sedangkan dengan   enzim α-amilase dan  glukoamilase  2  ml  diperoleh  alkohol  masing  –  masing  kadarnya  9,5  %  .    Hasil  studi menunjukan  bahwa  umbi  kimpul  tersebut    dapat  digunakan  sebagai  sumber  bahan  untuk memproduksi bioetanol.Kata kunci:  umbi kimpul, fermentasi dan  bioetanol
PENGEMBANGAN PRODUKSI BIOGAS DARI LIMBAH PEMBUATAN BIODIESEL JARAK PAGAR (Jatropha curcas seed cake) Y Yufidani; Bakti Jos; Siswo Sumardiono
JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Volume 2, Nomor 3, Tahun 2013
Publisher : Jurusan Teknik Kimia, Fakultas Teknik, Universitas Diponegoro,

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (208.554 KB)

Abstract

Biogas is a fermentation process using anaerobic bacteria to convert organic compounds into gas with high composition of methane. Use of jatropha curcas as a biodiesel’s resources remains a problems, seed cake of jatropha curcas contains phorbol esters that is toxic. This research focused on getting an optimum yield of biogas production from jatropha curcas seed cake using additive material to reach optimum C/N ratio. Optimum C/N ratio on biogas production was range 20-30, but jatropha curcas seed cake had C/N ratio about 9/1, so it needs to be added carbon source in order to achieve optimum C/N ratio. Carbon sources that added were paddy straw and tapioca wastewater as a solvent. Process of biogas production in this research use 3 variables, that are the number of jatropha seed cake total solid, the addition of paddy straw, and using tapioca wastewater as solvent. The result showed that the optimum composition in biodigester was jatropha seed cake 6% w/v, paddy straw 3% w/v, ruminant bacteria 10% v/v, and water as solvent. The yield of biogas reached 0,163 m3/kg total solid.
OPTIMALISASI EKSTRAKSI DAN UJI STABILITAS PHYCOCYANIN DARI MIKROALGA Spirulina platensis Prayudi Eko Setyawan; Yudha Satria; Bakti Jos
JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Volume 2, Nomor 2, Tahun 2013
Publisher : Jurusan Teknik Kimia, Fakultas Teknik, Universitas Diponegoro,

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (152.913 KB)

Abstract

Spirulina platensis adalah salah satu mikroalga penghasil Phycocyanin yang relatif cepat berproduksi dan mudah dalam sistem pemanenannya. Phycocyanin yang secara struktural mirip dengan β-karoten merupakan pigmen biru alami yang berharga dan banyak dimanfaatkan pada bidang kosmetik, obat-obatan dan farmasi. Tujuan yang ingin dicapai dalam penelitian ini adalah melakukan studi evaluasi produksi Phycocyanin dengan teknik ekstraksi dengan beberapa pelarut polar pada berbagai konsentrasi untuk mendapatkan hasil ekstrak yang maksimum. Metode penelitian yang diterapkan dalam penelitian ini memiliki beberapa tahap yaitu persiapan bahan, ekstraksi, studi kelarutan Phycocyanin, dan uji stabilitas Phycocyanin. Variabel berubah dalam penelitian ini adalah jenis pelarut polar Air, Asam asetat 70%, 75%, 80%, Amonium sulfat 50%, 55%, 60%. Analisa hasil kadar Phycocyanin yang terkstrak menggunakan metode spektrofotometri. Hasil pengamatan menghasilkan ekstrak zat warna biru yang memiliki intensitas warna tertinggi dengan absorbansi maksimalnya 620 nm. Pelarut asam asetat 80% merupakan pelarut yang paling efektif mengekstrak zat warna biru Phycocyanin dibandingkan air dan amonium sulfat. Ekstraksi dipengaruhi oleh pH yaitu kenaikan serapan (absorbansi) dengan meningkatnya pH dan tidak dipengaruhi oleh suhu dan lama penyimpanan zat warna.
MODIFIKASI UBI KAYU DENGAN PROSES FERMENTASI MENGGUNAKAN STARTER Lactobacillus casei UNTUK PRODUK PANGAN Muchlis Riki Darmawan; Patrick Andreas; Bakti Jos; Siswo Sumardiono
JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Volume 2, Nomor 4, Tahun 2013
Publisher : Jurusan Teknik Kimia, Fakultas Teknik, Universitas Diponegoro,

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (197.377 KB)

Abstract

Modification of cassava flour(MOCAF) is fermented cassava flour biomass with the help of microorganisms. Modification of cassava flour has a protein content and properties of the physicochemical better than regular cassava flour (without fermenting). Manufacture of modified cassava flour through several stages, namely the preparation of cassava (peeling, washing and cutting), fermentation, drying and the process of conversion chips dried into flour. Modified cassava flour can be produced by fermentation using a wide variety of microorganisms such as the culture of the Lactobacillus casei group of lactic acid.This research aims to know the influence of the concentration of a starter, a thick piece of cassava chips and the addition of nutrients to increased levels of protein as well as the changing nature of the resulting physicochemical. Fermentation is carried out using lactic acid cultures of Lactobacillus casei starter with a concentration of 1%, 3%, and 5% V and nutrients used is ammonium hydrogen phosphate 5% w. In the fermentation process used pieces of 2 mm thickness of chips, 4 mm and 6 mm.The fermentation process is carried out for 72 hours, with the room temperature. From the results obtained: improvement of the highest protein of 3.68% in 2 mm, 5% V variable,% solubility best of 1.63% at 2 mm, 5% V variable, swelling power best of 17.8% in 2 mm, 1% V variable,% carboxylic 0.4% on the largest variables 2 mm ,5% the best tensile strength in noodle products of 0,138 N/mm2 with ratio of 10% MOCAF and 90% of the flour, and pilus expand power of 261,71% on 5% V variable.
PROSES PRODUKSI BIODIESEL DARI MINYAK BIJI KARET DENGAN PROSES REAKTIF DISTILASI Jonathan Ginting; Praditya Nugraha; Bakti Jos
JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Volume 2, Nomor 2, Tahun 2013
Publisher : Jurusan Teknik Kimia, Fakultas Teknik, Universitas Diponegoro,

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (165.402 KB)

Abstract

Harga minyak bumi yang terus melambung tinggi memaksa terus dilakukannya upaya pencarian dan penelitian sumber energi alternatif baru. Salah satu sumber energi alternatif yang paling menjanjikan adalah biodiesel dari minyak biji karet. Dikarenakan bahan baku yang dapat diperbaharui dan tersedia melimpah. Dalam penelitian ini menggunakan proses reaktif distilasi dimana proses konversi dan pemisahan berlangsung secara serentak atau sinambung. Paremeter operasi yang akan dipelajari rasio katalis dan suhu serta pengaruhnya terhadap karakteristik produk biodiesel yang dihasilkan .Hasil analisis karakteristik bahan diperoleh kadar minyak yang cukup tinggi yakni 50,5%. Konversi minyak menjadi metil ester yang diperoleh paling besar adalah sebesar 25,86% . Variabel perbandingan volume asam lemak bebas dengan methanol lebih berpengaruh dibandingkan dengan variabel temperatur.
UV Irradiation and Ozone Treatment of κ-Carrageenan: Kinetics and Products Characteristics Aji Prasetyaningrum; Widayat Widayat; Bakti Jos; Yudhy Dharmawan; Ratnawati Ratnawati
Bulletin of Chemical Reaction Engineering & Catalysis 2020: BCREC Volume 15 Issue 2 Year 2020 (August 2020)
Publisher : Department of Chemical Engineering - Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.15.2.7047.319-330

Abstract

The low molecular weight (LMW) of sulfated polysaccharides including k-carrageenan, is shows a wide spectrum of biological activities. This research investigates the influence of UV irradiation, ozone (O3), and the combination of O3/UV methods on the depolymerization of k-carrageenan. The depolymerization kinetics of k-carrageenan using the Advanced Oxidation Process (UV/O3) was also studied. Furthermore, the intrinsic viscosity method was used to determine the average molecular weight of the research sample, and a mathematical model was developed to predict the kinetic rate constant, as a function of ozone dosage and UV irradiation intensity. Therefore, the physicochemical and morphological properties of the degraded k-carrageenan were analyzed by FT-IR, SEM, and XRD. The intrinsic viscosity k-carrageenan decreases with increasing UV light intensity and ozone concentration. The combination of UV/O3 treatment appeared to be more effective than the individual approaches, as the highest kinetic rate constant for depolymerization was 1.924×10-4 min-1, using 125 mg/L ozone concentration and 40 mW/cm2 of UV lamp intensity. This research also evaluated the relationship between various experimental conditions, including UV lamp power dissipation and ozone concentration on the reaction kinetics model, and the results suggest that lower effect is contributed by UV irradiation intensity. In addition, FT-IR spectra showed the absence of any significant change in the functional properties of k-carrageenan treated with UV and O3 processes, although the morphological properties of the LMW k-carrageenan were rougher and more porous than the native k-carrageenan. Copyright © 2020 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0). 
Inhibition Effect of Ca2+ Ions on Sucrose Hydrolysis Using Invertase Hargono Hargono; Bakti Jos; Abdullah Abdullah; Teguh Riyanto
Bulletin of Chemical Reaction Engineering & Catalysis 2019: BCREC Volume 14 Issue 3 Year 2019 (December 2019)
Publisher : Department of Chemical Engineering - Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (382.156 KB) | DOI: 10.9767/bcrec.14.3.4437.646-653

Abstract

Fermentable sugar for bioethanol production can be produced from molasses due to its high sucrose content but Ca2+ ions found in the molasses may affect the hydrolysis. Therefore, this paper was focused to study the effect of Ca2+ ions as CaO on sucrose hydrolysis using invertase and to obtain the kinetic parameters. The kinetic parameters (KM and Vmax) were obtained using a Lineweaver-Burk plot. The value of KM and Vmax parameters were 36.181 g/L and 21.322 g/L.h, respectively. The Ca2+ ions act as competitive inhibitor in sucrose hydrolysis using invertase. Therefore, the inhibition mechanism was followed the competitive inhibition mechanism. The value of inhibition constant was 0.833 g/g. These parameters were obtained from the non-substrate inhibition process because this study used the low substrate concentrations which means the fermentable sugar production was low. Hence, there were still more challenges to studying the simultaneous effect of substrate and Ca2+ on sucrose hydrolysis to produce high fermentable sugar. 
Kinetics of Oxidative Depolymerization of κ-carrageenan by Ozone Aji Prasetyaningrum; Ratnawati Ratnawati; Bakti Jos
Bulletin of Chemical Reaction Engineering & Catalysis 2017: BCREC Volume 12 Issue 2 Year 2017 (August 2017)
Publisher : Department of Chemical Engineering - Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (708.652 KB) | DOI: 10.9767/bcrec.12.2.805.235-242

Abstract

Depolymerization kinetics of κ-carrageenan by ozone treatment has been studied at various pHs and times. The purified κ-carrageenan with the initial molecular weight of 271 kDa was dispersed in water to form (1 % w/v) solution. Ozone with 80±2 ppm concentration and constant flow rate of 3 L.min-1 was bubbled into the κ-carrageenan solution. The experiments were conducted at pH of 3, 7, and 10 at     different times (5, 10, 15, and 20 minutes) of ozonation. The viscosity of the solution was measured   using Ubbelohde capillary viscometer, which was then used to find the number-average molecular weight by Mark-Houwink equation. The number-average molecular weight data was treated using zero, first, and the second-order reaction kinetics model, to obtain the kinetics of κ-carrageenan depolymerization. The depolymerization is assumed to occur by random scission. The results show that the kinetics rate constant of κ-carrageenan depolymerization is higher at lower pHs. The second-order model is more suitable for describing the kinetics of depolymerization of κ-carrageenan by ozonation process. The rate constants for the second-order kinetics model are 5.45×10-4 min-1, 1.27×10-4 min-1, and 7.21×10-5 min-1 for pH 3, 7, and 10, respectively. The actual values of reaction order under acid and    alkali conditions are ranging from 1.88 to 1.90. 
Kinetics of the Enzymatic Hydrolysis of Sweet Cassava Starch and Bitter Cassava Flour and Gadung (Dioscorea hispida Dennst) Flour at Low Temperature Hargono Hargono; Bakti Jos; Andri Cahyo Kumoro
Bulletin of Chemical Reaction Engineering & Catalysis 2017: BCREC Volume 12 Issue 2 Year 2017 (August 2017)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (111.333 KB) | DOI: 10.9767/bcrec.12.2.808.256-262

Abstract

Starch is a potential substrate for this purpose, but the extra cost is needed to hydrolyze it into reducing sugar. As an alternative to the expensive and energy demanding conventional hydrolysis process, the low-temperature hydrolysis is being studied. Granular Starch Hydrolysing Enzyme (GSHE) was used in the process to degrade starch into reducing sugar at 30°C and pH 4. The substrates included bitter cassava flour, sweet cassava starch, and gadung flour. Starch concentrations studied were 50, 100, 150, 200, 250, 300, 350, and 400 g/L, respectively, while concentration of enzyme was 1.5 % (w/w). The optimum condition of the process was hydrolysis using 200 g/L of substrate concentration and enzyme  concentration of 1.5% for 12 h. It was found that the reducing sugar was  49.3  g/L and the productivity of reducing sugar (Qrs) was 4.11 (gL-1 h-1).   Lineweaver-Burk plot of Michaelis-Menten equation was used to study the inhibition kinetics. The Michaelis-Menten constants (Km)  for these three substrates were determined as 141.64 g/L, 137,64 g/L and 140.84 g/L for bitter cassava flour, sweet cassava starch, and gadung flour, respectively. The value of  Vm/Km, which denotes the affinity of the enzyme to the substrate, were determined and compared, and the result showed that the affinity (Vm) to the enzyme to this substrate followed  the order of sweet cassava starch˃ bitter cassava flour˃ gadung flour, and all are non-competitive inhibitor, while the  Ki value was 0.022 h -1. 
PENGUATAN USAHA MIKRO DAN KECIL KERUPUK KULIT IKAN CAP MANTAP DI MLATIBARU, SEMARANG DALAM UPAYA PENCAPAIAN SUSTAINABLE DEVELOPMENT GOALS (SDGs) Dessy Ariyanti; Bakti Jos; Andri Cahyo Kumoro; Aji Prasetyaningrum; Diah Susetyo Retnowati
Jurnal Pasopati : Pengabdian Masyarakat dan Inovasi Pengembangan Teknologi Vol 4, No 1 (2022)
Publisher : Fakultas Teknik Universitas Diponegoro

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Abstract

Peran usaha mikro, kecil, dan menengah (UMKM) untuk merealisasikan tujuan pembangunan Berkelanjutan (Sustainable Development Goals SDGs) terutama Tujuan 8 yaitu  mendukung pertumbuhan ekonomi yang inklusif dan berkelanjutan, tenaga kerja penuh dan produktif dan pekerjaan yang layak bagi semua di Indonesia sangat besar. Salah satu UMK yang berada di daerah Mlati Baru, Kota Semarang adalah UMK Kerupuk Kulit Ikan Cap Mantap. UMK ini didirikan oleh Bapak Afnan Abdul Syaid pada tahun 2015. UMK ini memerlukan pendampingan sehingga dapat lebih berdaya dan berkembang. Tantangan yang dialami oleh UMK Kerupuk Kulit Ikan Cap Mantap ini adalah proses produksi yang masih mengandalkan cuaca, terutama di musim hujan, proses pengeringan kulit ikan basah sulit dilakukan dan waktu yang dibutuhkan menjadi sangat lama. Tantangan yang kedua adalah keterbatasan alat untuk packing sehingga kerupuk menjadi mudah rusak dan turun kualitasnya. Tantangan yang selanjutnya adalah pemasaran yang selama ini hanya dilakukan secara konvensional yaitu dijajakan di beberapa toko oleh-oleh dan supermarket. Pencapaian target tersebut diupayakan dengan berbagai metode dan kegiatan yang telah disusun yaitu survey awal, riset pasar, analisa SWOT, penyusunan strategi penguatan dan pendampingan, dimana Kegiatan-kegiatan tersebut ditargetkan untuk menghasilkan: Data UMK Kerupuk Kulit Ikan Cap Mantap, Data terbaru hasil riset pasar usaha yang serupa, Analisa SWOT dari UMK Kerupuk Kulit Ikan Cap Mantap, Strategi Penguatan Kerupuk Kulit Ikan Cap Mantap. Luaran yang ingin dicapai pada kegiatan ini adalah pengetahuan tepat guna yang dapat  diimplementasikan oleh UMK Kerupuk Kulit Ikan Cap Mantap di Mlatibaru, Semarang dalam upaya peningkatan kapasitas produksi dan pemasaran dari produk yang dihasilkan. Kata kunci : UMKM, kerupuk kulit ikan, pemberdayaan