Jurnal Rekayasa Proses https://dev.journal.ugm.ac.id/v3/jrekpros <p><img src="/v3/public/site/images/vncnt_shs/s21.png" width="204" height="74"></p> <div id="journalDescription"> <p><strong>Accredited by the Director General of Strengthening the Research, Technology and Higher Education of the Republic of Indonesia No. 158/E/KPT/2021 as SINTA 2 (2020-2025).<br></strong></p> <p>Jurnal Rekayasa Proses (J. Rek. Pros.) is an open-access, peer-reviewed journal published by the Department of Chemical Engineering, Faculty of Engineering, Universitas Gadjah Mada. The journal is dedicated to the dissemination of cutting-edge research and developments in the field of chemical and biochemical process engineering. It provides a platform for exploring and optimizing processes at various scales, ranging from micro to macro, including full plant scale. The journal covers a broad spectrum of topics, including kinetics and catalysis, separation and purification systems, process systems engineering, oil, gas, and coal technologies, particle technology, mineral process engineering, material and biomaterial engineering, bioresource and biomass engineering, biochemistry and bioprocess engineering, biomedical engineering, and issues related to energy, water, environment, and sustainability. J. Rek. Pros. aims to foster the exchange of knowledge and ideas among researchers, practitioners, and academics, contributing to advancements in these critical areas of engineering. For more details, please see the scope and topics covered by the journal: <a href="https://jurnal.ugm.ac.id/v3/jrekpros/focus-and-scope">https://jurnal.ugm.ac.id/v3/jrekpros/focus-and-scope</a></p> <p>J. Rek. Pros. publishes&nbsp;<em>communications, articles, and reviews</em>. The first volume of J. Rek. Pros. has been published in 2007 and continued until today with 2 (two) issues of publication each year. The minimum number of articles for each issue is 5 (five) articles. The official language of the journal is Bahasa Indonesia, but manuscripts in English are also welcomed. Manuscript submission and reviewing process is fully conducted through online journal system (<a href="https://jurnal.ugm.ac.id/v3/jrekpros">https://jurnal.ugm.ac.id/v3/jrekpros</a>) using a double-blind review process.&nbsp;</p> <p>&nbsp;</p> </div> Jurnal Rekayasa Proses en-US Jurnal Rekayasa Proses 1978-287X Optimasi proses metilasi brazilein hasil ekstrak kayu secang (Caesalpinia sappan linn) sebagai bahan pewarna merah alami untuk tekstil https://dev.journal.ugm.ac.id/v3/jrekpros/article/view/11026 <p>Salah satu upaya untuk mengurangi penggunaan pewarna sintesis yang berbahaya bagi manusia dan lingkungan adalah dengan menggunakan pewarna alami. Salah satu bahan pewarna alami yang potensial di Indonesia adalah kayu Secang (<em>Caesalpina sappan L.</em>). Kayu secang mengandung senyawa brazilein yang mampu menghasilkan warna merah. Namun, warna merah yang dihasilkan oleh brazilein sangat tidak stabil terhadap perubahan pH. Tujuan penelitian ini adalah meningkatkan kestabilan warna brazilein terhadap perubahan pH dengan menggunakan metode metilasi. Metilasi dilakukan dengan menggunakan dimetil karbonat (DMC) sebagai agen metilasi yang dikombinasikan dengan kalium iodide (KI) dan kalium karbonat (K<sub>2</sub>CO<sub>3</sub>). Metilasi dilakukan menggunakan metode reflux dengan variasi suhu (50, 60, dan 70&nbsp;<sup>o</sup>C), waktu (3, 4, dan 5 jam), dan rasio pereaktan (1:5, 1:10, dan 1:15 g brazilein/mL DMC). Kestabilan warna dinyatakan sebagai nilai absorbansi yang diukur menggunakan spektrofotometer UV-Vis pada panjang gelombang 535,6 nm. Optimasi kondisi metilasi dilakukan menggunakan&nbsp;<em>Response Surface Methodology</em>&nbsp;(RSM). Hasil yang optimum didapatkan pada suhu 70&nbsp;<sup>o</sup>C, waktu 3,46 jam, dan rasio pereaktan 0,12 g brazilein/mL DMC. Pada kondisi tersebut, penyimpangan nilai absorbansi asam sebesar 28,12% sedangkan penyimpangan nilai absorbansi basa sebesar 0,02%. Kestabilan warna brazilein berhasil ditingkatkan dengan melakukan metilasi pada kondisi optimum.</p> Muhammad Khoirul Muslimin Edia Rahayuningsih Aswati Mindaryani Copyright (c) 2024 The Author(s) https://creativecommons.org/licenses/by-sa/4.0 2024-09-30 2024-09-30 18 2 89 99 10.22146/jrekpros.82068 Optimization of gembili (Dioscorea esculenta L.) starch partial hydrolysis in maltodextrin production with microwave assist using acetic acid catalyst https://dev.journal.ugm.ac.id/v3/jrekpros/article/view/16692 <p>The purpose of this study was to determine the optimal conditions for partial hydrolysis of <em>gembili</em> starch in the maltodextrin production. Novelty of this research is the use of acetic acid as a substitute for commonly used acids and microwaves for process efficiency. The process of maltodextrin production includes raw material pretreatment, gelatinization, liquefaction, drying and analysis. Variations in liquefaction time (30, 40, 50 min), microwave power (300, 400, 500 W) and acetic acid concentration (14, 15, 16 %) were used as independent variables. The equivalent dextrose analysis results were 9.389 ± 0.042 to18.980 ± 0.201%, the density analysis results were 1.059416 to 1.107796 g/ml and viscosity analysis results were 0.430554 to 0.974663 cP. This study produces that 96.705% of the total variability in response can be explained in the regression equation. Critical value of this study estimated dextrose equivalent value of maltodextrin produced of 16.636% and the validation of it is 16.254 ± 0,074%.</p> Muhammad Zaki Riadhus Shalihin Vita Paramita Septi Enjelina Sitio Fitri Dwi Nurlaili Hermawan Dwi Ariyanto Copyright (c) 2024 The Author(s) https://creativecommons.org/licenses/by-sa/4.0 2024-09-30 2024-09-30 18 2 100 108 10.22146/jrekpros.83823 Enzymatic saccharification of liquid sugar from cassava peel starch: Optimization and characteristics https://dev.journal.ugm.ac.id/v3/jrekpros/article/view/13727 <p>The province of Lampung generated 2.6 million tons of cassava and 0.28 million tons of inner cassava peel waste in 2020. This demonstrates that the value of production is closely correlated with the amount of trash generated. 44-59% starch is still present in the waste from the inside of cassava peels, and this starch can be used as an input to make liquid sugar. Using the Response Surface Methodology (RSM) tool, this study attempts to optimize the saccharification process with modifications in duration (2, 4, and 8 h) and temperature (55, 60, and 65°C). Liquification and saccharification are the enzymatic processes used to make liquid sugar from cassava peel. According to study findings, the starch yield from cassava peels was 11.54%, with corresponding levels of water, ash, starch, and crude fiber of 13.53, 0.61, and 88.32%, and 1.025%, respectively. The yield of liquid sugar obtained from saccharification of cassava peel starch is 58.36%. The water and ash contents are 58.07, 16.95, and 0.11%, respectively, with the quality of lowering sugar content. Using the RSM approach, this study was able to optimize the saccharification process of liquid sugar from cassava peel starch at a temperature of 67.07 °C and a time variation of 6.8 hours. The optimized conditions resulted in a higher yield of liquid sugar from cassava peel starch. This study highlights the potential of utilizing cassava peels as a valuable source for liquid sugar production.</p> Indah Maulidia Oktaf Rina Shintawati Vida Elsyana Adityas Agung Ramandani Mawar Siti Purnani Copyright (c) 2024 The Author(s) https://creativecommons.org/licenses/by-sa/4.0 2024-09-30 2024-09-30 18 2 109 117 10.22146/jrekpros.13727 Sintesis selulosa asetat dari limbah daun nanas memanfaatkan DES CHCL-OA untuk meningkatkan ekstraksi selulosa sebagai bahan filter masker kain https://dev.journal.ugm.ac.id/v3/jrekpros/article/view/13255 <p>Selulosa asetat adalah senyawa organik yang terbentuk dari substitusi gugus hidroksil pada selulosa dengan gugus asetil. Senyawa ini memiliki potensi sebagai bahan baku untuk filter masker. Sintesis selulosa asetat dilakukan dengan mereaksikan senyawa selulosa dengan anhidrida asetat. Penelitian ini memodifikasi metode yang telah dilakukan oleh peneliti sebelumnya dengan menggunakan DES ChCl-OA dalam proses isolasi selulosa dari daun nanas. Tahapan penelitian meliputi persiapan daun nanas dan DES ChCl-OA, isolasi selulosa, pengujian kadar selulosa dan lignin, sintesis selulosa asetat, karakterisasi selulosa asetat, dan pembuatan filter. Selulosa daun nanas hasil preparasi menggunakan DES ChCl-OA menunjukkan kemampuan untuk mengisolasi sekitar 57,38% dari total selulosa yang terkandung dalam serat daun nanas. Selanjutnya, isolat selulosa tersebut diasetilasi menggunakan anhidrida asetat dengan variasi percobaan tertentu, dan menghasilkan selulosa asetat terbaik untuk pembuatan filter dengan yield antara 79,6-80,6%, kadar asetil sekitar 40,74-40,96%, dan DS (<em>Degree of Substitution</em>) sebesar 2,56. Variabel anhidrida asetat sebanyak 17,5 mL dan waktu asetilasi selama 1,5 jam memberikan hasil terbaik. Modifikasi pada proses persiapan serat limbah daun nanas menggunakan DES ChCl-OA terbukti efektif dan efisien dalam mengisolasi senyawa selulosa. Hasil penelitian terbukti memberikan hasil lebih baik daripada sebelumnya.</p> Puji Nurhidayah Anggun Puspitarini Siswanto Copyright (c) 2024 The Author(s) https://creativecommons.org/licenses/by-sa/4.0 2024-09-30 2024-09-30 18 2 118 128 10.22146/jrekpros.13255 Simulation and evaluation of fuel distribution line from fuel terminal Tuban into integrated terminal Perak at PT Pertamina MOR V through ASPEN Plus® modeling https://dev.journal.ugm.ac.id/v3/jrekpros/article/view/14106 <p>This research aims to 1) to determine operating conditions that correspond to the amount of fuel needed to be distributed, 2) visualize the profile of pressure changes with pipe distance, and 3) compare actual conditions with simulated conditions. The research method consists of simulation of energy loss in the form of pressure drop for each type of fuel oil (gasoline and gasoil) using ASPEN Plus® software. Research results show that a greater pump pressure of 87 bar is required to distribute gasoil, compared to gasoline which only uses 82 bar to reach ideal atmospheric pressure at 750 m<sup>3</sup>/hour. Reduction in fuel pumping pressure is close to linearity, where pumping pressure will continue to decrease as piping distribution distance increases. % error is obtained by comparing the simulation results with the industrial standard which is evidenced by % error of 7.69 (moderate) in the type of gasoline fuel and % error value of 1.81 (strong) in the type of gasoil fuel. This research has been in accordance with the real conditions in the field, so it can predict the right conditions to maximize the process.</p> Yosef Budiman Dwita Cahaya Pratiwi Umi Rofiqah Ifa Puspasari Yudha Whastu Wibowo Moh. Khotip Hendrix Eko Vebriono Arif Hidayat Copyright (c) 2024 The Author(s) https://creativecommons.org/licenses/by-sa/4.0 2024-09-30 2024-09-30 18 2 129 136 10.22146/jrekpros.14106 Pemanfaatan tandan kosong kelapa sawit dari produksi pabrik kelapa sawit Cikasungka sebagai alternatif pembuatan tinta printer https://dev.journal.ugm.ac.id/v3/jrekpros/article/view/15659 <p>Tandan Kosong Kelapa Sawit (TKKS) merupakan limbah organik yang sangat banyak dijumpai diperkebunan kelapa sawit. TKKS memiliki nilai guna yang cukup tinggi karena terdapat kandungan serat di dalamnya. Namun, pemanfaatan TKKS di Pabrik Kelapa Sawit (PKS) masih sebatas sebagai pupuk. Oleh karena itu, pada riset ini dilakukan pemanfaatan kelapa sawit sebagai bahan baku pigmen organik untuk pembuatan tinta <em>printer</em>. Pigmen organik pada riset ini dibuat melalui beberapa tahapan, antara lain penghalusan bahan dengan parang, pengeringan dengan sinar matahari, proses karbonisasi (pengarangan) pada suhu 450<sup>o</sup>C menggunakan serangkaian alat karbonisasi, penghalusan arang (karbon) TKKS, pengayakan serbuk karbon dengan <em>screen mesh</em> T200 dan tahap pembuatan tinta <em>printer</em> dilakukan melalui pencampuran karbon TKKS dengan aquadest, alkohol, dan gum arab. Tinta yang dihasilkan akan diuji viskositas, uji transmitansi cahaya, uji adhesi, uji densitas, dan uji performa tinta. Hasil riset ini menunjukkan bahwa produk tinta <em>printer</em> terbaik didapatkan pada komposisi massa 2 g karbon dengan 5 mL alkohol, yang dicampur dengan bahan perekat berupa 3,5 g gum arab dalam 22,5 mL aquadest. Hasil uji cetak, transmitansi dan adhesi telah sesuai dengan Standar Nasional Indonesia (SNI) namun untuk uji viskositas perlu diteliti lebih lanjut.&nbsp;</p> Dandi Syahrul Gunawan Ridho Pardosi Timbul Widodo Muhammad Iqbal Nabillah Dwi Africia Aris Sandi Lestari Hetalesi Saputri Copyright (c) 2024 The Author(s) https://creativecommons.org/licenses/by-sa/4.0 2024-09-30 2024-09-30 18 2 137 143 10.22146/jrekpros.15659 Comparative Study of Single and Multiple Pre-treatments of Rice Straw on Cellulose Content for Bioethanol Production https://dev.journal.ugm.ac.id/v3/jrekpros/article/view/13187 <p><em>Utilization of lignocellulosic biomass for ethanol production has increased. One source of lignocellulosic is rice straw which contains cellulose, hemicellulose, and lignin. Before being used as an ingredient for bioethanol production, it needs to be pre-treated with alkali or acid. One of the factors that affect pre-treatment is the concentration of alkali or acid. The purpose of this study was to determine the concentration of NaOH and H<sub>2</sub>SO<sub>4 </sub>in single and multiple pre-treatment which produced the highest cellulose content for bioethanol production. The concentration of NaOH and H<sub>2</sub>SO<sub>4</sub> are 0.75 M; 1 M and 1.5 M. Pre-treatment was carried out at room temperature for 90 minutes. Cellulose, hemicellulose, and lignin content were analyzed using the Chesson Datta method. The variable that produced the highest cellulose was continued to the Simultaneous Saccharification and Fermentation (SSF) at room temperature and analyzed for reducing sugar and bioethanol contents. The results showed that the highest cellulose content of 60.79% was found in single pre-treatment of 0.75 M H<sub>2</sub>SO<sub>4 </sub>of 44.89%, 1.5 M NaOH and multiple pretreatments of 0.75 M H<sub>2</sub>SO<sub>4</sub> – 1.5 M NaOH of 68.14%. The highest bioethanol content was obtained in the multiple pretreatments of 0.75 M H<sub>2</sub>SO<sub>4</sub> – 1.5 M NaOH of 23%.</em></p> Luthfi Kurnia Dewi Ni Made Zevika Miranda Hashinatul Fikrial Rabbani Wa Ode Cakra Nirwana Copyright (c) 2024 The Author(s) https://creativecommons.org/licenses/by-sa/4.0 2024-09-30 2024-09-30 18 2 144 153 10.22146/jrekpros.13187 Physical properties and GC/MS analysis of pyrolysis oil from tire and plastic waste (HDPE/high-density polyethylene and PP/polypropylene) https://dev.journal.ugm.ac.id/v3/jrekpros/article/view/12342 <p><em>Pyrolysis is an innovative technology that can convert various types of waste into high-value products. Pyrolysis Oil (PO) can be used as an alternative fuel. The objective of this research aims to determine the physical properties and the content of chemical compounds in the pyrolysis oil of waste tire and plastic, which are then compare to the characteristics of commercial fuel. Pyrolysis was carried at 350℃ for 4 hours using motorcycle tire and plastic waste (HDPE and PP) as raw materials. The result shows that the physical properties of PO HDPE C are similar to gasoline with a density of 0.807 g/mL, dynamic viscosity of 0.623 cP, and kinematic viscosity of 0.771 cSt. However, its calorific value is still very low. PO PP C has a calorific value almost comparable to commercial fuel of 38.24 MJ/kg. Meanwhile for PO tires, the properties unqualified characteristics of fuel. GC/MS analysis shows that PO Tires C1 has a high content of olefins and aromatic compound. PO HDPE C has a high content of paraffin and olefin compound. Pyrolysis oil of tires and plastic waste have the potential to be used as fuel. Pyrolysis conditions to produce PO with characteristics similar to fuel.</em></p> Al Buchori Nur Fajar Niken Safitri Khoirina Dwi Nugrahaningtyas Copyright (c) 2024 The Author(s) https://creativecommons.org/licenses/by-sa/4.0 2024-09-30 2024-09-30 18 2 154 162 10.22146/jrekpros.12342 Increasing The Strength of Cellular Lightweight Concrete Bricks with The Addition of Bamboo Fiber https://dev.journal.ugm.ac.id/v3/jrekpros/article/view/15320 <p>This research aims to obtain technology for improving the quality of CLC (Celullar Lightweight Concrete) bricks to be equivalent to AAC (Autoclaved Aerated Concrete). This is a response to the rapid development, especially in the property sector, which is followed by the increasing need for bricks as the main material for building walls. CLC bricks are an alternative product other than red bricks that have the potential to pollute the environment because in the production process there is burning. The problem is that the quality of CLC bricks is relatively lower compared to AAC bricks. The method is to add bamboo fiber as a reinforcement and optimize the elements. The design of the experiment was made using the Taguchi Method, but preliminary experiments had previously been carried out to predict the percentage of elements. The research includes manufacturing process technology and quality testing on samples. Bamboo fiber-reinforced CLC bricks are obtained with an optimal composition of 0.5% fiber and a ratio of cement mass to sand mass of 1:1.6. This sample has a compressive strength of 1.1235 MPa and a bending strength of 1.1723 MPa. From this composition, samples were obtained with an average compressive strength of 1.1285 MPa and an average bending strength of 1.3551 MPa. Thus, it can be concluded that the addition of fiber can increase the strength of CLC bricks to be equal to or stronger than AAC bricks on the market.</p> An-Nisa Magnolia Jamiatul Akmal Martinus Martinus Shirley Savetlana Masdar Helmi Copyright (c) 2024 The Author(s) https://creativecommons.org/licenses/by-sa/4.0 2024-09-30 2024-09-30 18 2 163 170 10.22146/jrekpros.15320 Efisiensi penurunan kadar COD dalam air limbah industri laundry menggunakan metode elektrokoagulasi https://dev.journal.ugm.ac.id/v3/jrekpros/article/view/12392 <p>Limbah <em>laundry</em> mengandung parameter pencemar yang tinggi, salah satunya adalah COD (<em>Chemical Oxygen Demand</em>). Kandungan pencemar tersebut berasal dari deterjen yang ditambahkan saat pencucian&nbsp; untuk menghilangkan noda pada pakaian. Pembuangan air limbah <em>laundry</em> secara langsung ke lingkungan dapat menyebabkan&nbsp; pencemaran&nbsp; dan kerusakan lingkungan. Salah satu alternatif yang dapat digunakan untuk&nbsp; mengatasi permasalahan air limbah industri laundry adalah dengan menggunakan metode elektrokoagulasi. Elektrokoagulasi merupakan salah satu metode pengolahan air limbah&nbsp; secara elektrokimia&nbsp; dengan melepaskan koagulan aktif dari elektroda. Proses pengolahan air limbah industri <em>laundry</em> menggunakan variasi waktu kontak 60; 90; dan 120 menit dengan variasi tegangan 10; 20; dan 30 volt. Pengolahan air limbah <em>laundry</em> menggunakan metode elektrokoagulasi terbukti mampu menurunkan kadar pencemar pada air limbah industri <em>laundry</em>. Variasi tegangan 30 volt dan waktu kontak 120 menit mampu menurunkan&nbsp; kadar COD hingga 72 mg/L dari kadar awal 864 mg/L dengan efisiensi penurunan mencapai angka 91,48%. Hasil analisis data menggunakan anova di dapatkan nilai <em>p-value</em> &lt; 0,05 yang artinya variasi tegangan dan waktu kontak berpengaruh signifikan terhadap penurunan COD pada air limbah industri <em>laundry</em> menggunakan metode elektrokoagulasi.</p> Aldo Rianda Purba Nama Ririn Endah Badriani Audiananti Meganandi Kartini Copyright (c) 2024 The Author(s) https://creativecommons.org/licenses/by-sa/4.0 2024-09-30 2024-09-30 18 2 171 178 10.22146/jrekpros.12392