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All Journal Jurnal Rekayasa Proses Jurnal Manajemen Teknologi Jurnal Teknik ITS IPTEK The Journal for Technology and Science Jurnal Sains dan Teknologi Journal of Engineering and Technological Sciences International Research Journal of Business Studies (E-Journal) Jurnal Teknik Industri: Jurnal Keilmuan dan Aplikasi Teknik Industri Indonesian Journal of Chemistry Jurnal Rekayasa Proses International Journal of Marine Engineering Innovation and Research Jurnal Teknik Kimia Indonesia Journal of Marine-Earth Science and Technology Makara Journal of Science Makara Journal of Technology Sewagati Jurnal Teknik Kimia dan Lingkungan Jurnal Teknologi Kimia Mineral Bulletin of Chemical Reaction Engineering & Catalysis International Research Journal of Business Studies Jurnal Rekayasa Proses
Sjarief Widjaja
Chemical Engineering Department, Institut Teknologi Sepuluh Nopember, Kampus ITS Sukolilo, Surabaya 6011
Arts Humanities Automotive Engineering Chemical Engineering, Chemistry & Bioengineering Chemistry Civil Engineering, Building, Construction & Architecture Computer Science & IT Control & Systems Engineering Decision Sciences, Operations Research & Management Earth & Planetary Sciences Economics, Econometrics & Finance Education Electrical & Electronics Engineering Energy Engineering Environmental Science Industrial & Manufacturing Engineering Languange, Linguistic, Communication & Media Materials Science & Nanotechnology Mechanical Engineering Physics Public Health Social Sciences Transportation Other

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Synergistic Effect of Two Type Cellulase Immobilized on Chitosan Microparticle as Biocatalyst for Coconut Husk Hydrolysis Afan Hamzah; Lidya Lorenta Sitompul; Irma Nurhanifah Fenda Putri; Soeprijanto Soeprijanto; Arief Widjaja
Indonesian Journal of Chemistry Vol 19, No 2 (2019)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (480.253 KB) | DOI: 10.22146/ijc.39714

Abstract

The effectivity of employing two types of cellulases from Aspergillus niger and Trichoderma resei covalently immobilized on chitosan microparticle was investigated. Reducing sugar from CMC yielded by immobilized cellulase from T. resei alone and A. niger alone was 0.316 g/L and 0.244 g/L, respectively. Simultaneous use of both cellulases shows a significant increase of reducing sugar produced to 1.020 g/L. The effective combination of this two types of cellulases also occurred when coconut husk was used as substrate. A very high enzyme coupling of 92.06% compared to free enzyme was obtained in the immobilization. Addition of GDA not only increased enzyme coupling to 100% but also improved sugar produced. Immobilized cellulase was successfully maintained its activity until 5 cycles
Lipid Production from Microalgae as a Promising Candidate for Biodiesel Production Widjaja, Arief
Makara Journal of Technology Vol. 13, No. 1
Publisher : UI Scholars Hub

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Abstract

Recently, several strains of microalgae have been studied as they contain high lipid content capable to be converted to biodiesel. Fresh water microalgae Chlorella vulgaris studied in this research was one of the proof as it contained high triacyl glyceride which made it a potential candidate for biodiesel production. Factors responsible for good growing of microalgae such as CO2 and nitrogen concentration were investigated. It was found that total lipid content was increased after exposing to media with not enough nitrogen concentration. However, under this nitrogen depletion media, the growth rate was very slow leading to lower lipid productivity. The productivity could be increased by increasing CO2 concentration. The lipid content was found to be affected by drying temperature during lipid extraction of algal biomass. Drying at very low temperature under vacuum gave the best result but drying at 60oC slightly decreased the total lipid content.
Development of Technology Parameter Towards Shipbuilding Productivity Predictor Using Cubic Spline Approach Suwasono, Bagiyo; Widjaja, Sjarief; Zubaydi, Achmad; Yuliadi, Zaed; Budiantara, I Nyoman
Makara Journal of Technology Vol. 14, No. 2
Publisher : UI Scholars Hub

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Abstract

Development of Technology Parameter Towards Shipbuilding Productivity Predictor Using Cubic Spline Approach. Ability of production processes associated with state-of-the-art technology, which allows the shipbuilding, is customized with modern equipment. It will give impact to level of productivity and competitiveness. This study proposes a nonparametric regression cubic spline approach with 1 knot, 2 knots, and 3 knots. The application programs Tibco Spotfire S+ showed that a cubic spline with 2 knots (4.25 and 4.50) gave the best result with the value of GCV = 56.21556, and R2 = 94.03%.Estimation result of cubic spline with 2 knots for the PT. Batamec shipyard = 35.61 MH/CGT, PT. Dok & Perkapalan Surabaya = 27.49 MH/CGT, PT. Karimun Sembawang Shipyard = 27.49 MH/CGT, and PT. PAL Indonesia = 19.89 MH/CGT.
Optimization of Sugarcane Bagasse Ash Utilization for Concrete Bricks Production Using Plackett-Burman and Central Composite Design Maktum Muharja; Rizki Fitria Darmayanti; Arief Widjaja; Yakub Hendrikson Manurung; Ilham Alamsah; Siska Nuri Fadilah
Jurnal Teknik Kimia dan Lingkungan Vol. 6 No. 1 (2022): April 2022
Publisher : Politeknik Negeri Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (896.009 KB) | DOI: 10.33795/jtkl.v6i1.282

Abstract

PT. Industri Gula Glenmore (PT. IGG) setiap tahunnya memproduksi 14.300 ton abu ampas tebu (AAT) sebagai hasil samping pembakaran boiler yang belum dimanfaatkan secara maksimal. Menariknya, AAT memiliki kandungan silika tinggi yaitu 68,5% yang dapat ditingkatkan nilainya sebagai substitusi parsial semen dalam pembuatan bata beton. Oleh karena itu, pada penelitian ini komposisi dan ukuran partikel AAT dioptimalkan dalam pembuatan bata beton. Optimasi dilakukan dengan menggunakan Response Surface Methodology (RSM) untuk memahami perilaku faktor-faktor signifikan yang mempengaruhi kuat tekan bata beton. RSM ditentukan dengan menggunakan software Design-Expert V11. Bata beton dibuat dengan perbandingan semen dan pasir menggunakan perbandingan 1:6 dengan variasi AAT 5% sampai 25% dari berat normal semen. Hasil pengujian di Workshop menunjukkan bahwa penggunaan Fly Ash dan kapur sebagai bahan pengikat untuk menggantikan sebagian semen dengan variasi 23, 26, 28, 30, dan 33% menghasilkan kuat tekan berturut-turut sebesar 56, 52, 49, 40, dan 34 kg/cm2. Dengan demikian, bata beton pada penelitian ini termasuk dalam mutu tingkat 3 berdasarkan SNI 03-0349-1989. Inovasi ini merupakan solusi untuk meningkatkan nilai tambah AAT dan menjadi peluang bisnis baru bagi PT. IGG di masa depan PT. The Glenmore Sugar Industry (PT. IGG) annually produces 14,300 tons of Sugarcane Bagasse Ash (SCBA) as a by-product of boiler combustion that has not been fully utilized. Interestingly, SCBA has a high silica content of 68.5%, which can be valorized as a partial substitution of cement in the manufacture of concrete bricks. Therefore, in this study the composition and particle size of SCBA were optimized in the manufacture of concrete bricks. Optimization was carried out by using Response Surface Methodology (RSM) to understand the behavior of significant factors affecting the compressive strength of concrete bricks. RSM was determined using the Design-Expert V11 software. Concrete bricks were made with a ratio of cement and sand using a ratio of 1:6 with a variation of bagasse ash 5% to 25% of the normal weight of the cement. The test results showed that the use of fly ash and lime as a binder to replace some cement with variations of 23%, 26%, 28%, 30%, and 33% resulted in a compressive strength of 56 kg/cm2, 52 kg/cm2, 49 kg/cm2, 40 kg/cm2, and 34 kg/cm2, respectively. Thus the concrete brick in this study was included in the quality level 3 based on SNI 03-0349-1989. This innovation is a solution to increase SCBA's added value and a new business opportunity for PT. IGG in the future.
Effect of Severity Factor on the Subcritical Water and Enzymatic Hydrolysis of Coconut Husk for Reducing Sugar Production Maktum Muharja; Nur Fadhilah; Rizki Fitria Darmayanti; Hanny Frans Sangian; Tantular Nurtono; Arief Widjaja
Bulletin of Chemical Reaction Engineering & Catalysis 2020: BCREC Volume 15 Issue 3 Year 2020 (December 2020)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.15.3.8870.786-797

Abstract

Preventing the further degradation of monomeric or oligomeric sugar into by-product during biomass conversion is one of the challenges for fermentable sugar production. In this study, the performance of subcritical water (SCW) and enzymatic hydrolysis of coconut husk toward reducing sugar production was investigated using a severity factor (SF) approach. Furthermore, the optimal condition of SCW was optimized using response surface methodology (RSM), where the composition changes of lignocellulose and sugar yield as responses. From the results, at low SF of SCW, sugar yield escalated as increasing SF value. In the enzymatic hydrolysis process, the effect of SCW pressure is a significant factor enhancing sugar yield. A maximum total sugar yield was attained on the mild SF condition of 2.86. From this work, it was known that the SF approach is sufficient parameter to evaluate the SCW and enzymatic hydrolysis of coconut husk. Copyright © 2021 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). 
A Performance Study of Home-Made Co-Immobilized Lipase from Mucor miehei in Polyurethane Foam on The Hydrolysis of Coconut Oil to Fatty Acid Dwina Moentamaria; Maktum Muharja; Tri Widjaja; Arief Widjaja
Bulletin of Chemical Reaction Engineering & Catalysis 2019: BCREC Volume 14 Issue 2 Year 2019 (August 2019)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.14.2.3848.391-403

Abstract

Bio‐based fatty acids (FAs) produced through hydrolysis of natural oils and fats are promising chemical feedstocks for increasing  the economic value of renewable raw materials. In this work, lecithin, gelatin, PEG, and MgCl2 were employed as the co-immobilized material of crude lipase Mucor miehei immobilization on the polyurethane foam (PUF) matrix for hydrolysis of coconut oil to Free Fatty Acid (FFA). The unconventional immobilized technique was used through cross-linking and covalent bond. Single factor analysis and response surface method were utilized to determine the optimum conditions of the hydrolysis reaction. After optimization, co-immobilized lipase was examined for storage stability at a temperature of 4°C and reusability performance. The optimum conditions for coconut oil hydrolysis were obtained on the co-immobilized-PUF ratio, water-oil ratio, and reaction time of 20.17 w/w, 4.45 w/w, and 20 h, respectively. Under these conditions, the acid value as lauric acid enhanced 573% to 3.21 mg KOH/g oil. Storage stability attained through remaining activity on free lipase, PUF-lipase, PUF-co-immobilized-lipase were 9.89%, 42.3%, and 91.88%, respectively. In this study, the application of PUF-co-immobilized lipase in hydrolysis reactions can be reused up to 5 times. Characteristics of the addition of co-immobilized lipase have been analyzed using Fourier Transform Infra Red (FTIR) and Scanning Electron Microscope (SEM), showing the presence of functional groups binding and the changes in the surface matrix structure. 
Enhancing Enzymatic Digestibility of Coconut Husk using Nitrogen-assisted Subcritical Water for Sugar Production Maktum Muharja; Nur Fadhilah; Tantular Nurtono; Arief Widjaja
Bulletin of Chemical Reaction Engineering & Catalysis 2020: BCREC Volume 15 Issue 1 Year 2020 (April 2020)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.15.1.5337.84-95

Abstract

Coconut husk (CCH) as an abundant agricultural waste in Indonesia has the potential to be utilized for sugar production, which is the intermediate product of biofuel. In this study, subcritical water (SCW) assisted by nitrogen (N2) was developed to enhance the enzymatic hydrolysis of CCH. SCW process was optimized by varying the operation condition: the pressure of 60-100 bar, the temperature of 150-190 °C, and the time of 20-60 min. The SCW-treated solid was subsequently hydrolyzed by utilizing a mixture of commercial cellulase and xylanase enzymes. The result shows that the optimum total sugar yield was obtained under the mild condition of SCW treatment, resulting in the sugar of 15.67 % and 10.31 % gained after SCW and enzymatic hydrolysis process, respectively. SEM and FTIR analysis of SCW-treated solid exhibited the deformation of lignin and solubilization of cellulose and hemicellulose, while XRD and TGA revealed an increase of the amount of crystalline part in the solid residue. The use of N2 in SCW treatment combined with enzymatic hydrolysis in this study suggested that the method can be considered economically for biofuel production from CCH waste in commercial scale. 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). 
Mathematical Modelling of Alkaline and Ionic Liquid Pretreated Coconut Husk Enzymatic Hydrolysis Akbarningrum Fatmawati; Ari Anggoro; Kamila Adila Muslim; Arief Widjaja; Tantular Nurtono; Hanny Frans Sangian
Bulletin of Chemical Reaction Engineering & Catalysis 2021: BCREC Volume 16 Issue 2 Year 2021 (June 2021)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.16.2.10306.331-341

Abstract

The problem of crude oil reserve shortage and air quality decline currently have led researches on renewable fuel such as bioethanol and biohydrogen. The attempt to provide such biofuel involves the utilization of enormously available wasted materials, lignocellulose. Coconut husk is one of such materials available in Indonesia. The previous work had reported the quantity of total reducing sugar produced after the enzymatic hydrolysis of pretreated coconut husk. The pretreatment methods used were dilute sodium hydroxide solution (1 and 4% w/v), 1,3-methylmethylimidazolium dimethyl phosphate ionic liquid and the combination of both methods. This work focused on constructing the mathematical model which describes the kinetic of those enzymatic hydrolysis reactions. Mathematical model expressions help describing as well as predicting the process behavior, which is commonly needed in the process design and control. The development of mathematical model in this work was done based on the total reducing sugar concentration resulted in batch hydrolysis reaction. The kinetic parameters including initial available substrate (S0), maximum reaction rate (rmax), and half-maximum rate constant (KM). According to the values of half-maximum rate constant (KM), the enzymatic hydrolysis performance of coconut husk treated using ionic liquid is better than that treated using dilute alkaline solution as the former had shown lower KM value and hence higher enzyme affinity to the substrate. The best hydrolysis result was performed using combination of 1% dilute sodium hydroxide solution and ionic liquid with kinetic model parameter of 0.5524 g/L.h of rmax, 0.0409 g/L of KM, and 4.1919 g/L of S0. Copyright © 2021 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). 
PENINGKATAN UNJUK KERJA HIDROLISIS ENZIMATIK JERAMI PADI MENGGUNAKAN CAMPURAN SELULASE KASAR DARI Trichoderma reesei DAN Aspergillus niger Anwar, Nadiem; Widjaja, Arief; Winardi, Sugeng
Makara Journal of Science Vol. 14, No. 2
Publisher : UI Scholars Hub

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Abstract

Increasing the Performance of Enzymatic Hydrolysis of Rice Straw Using Mixed Crude Cellulases from Trichoderma reesei and Aspergillus niger. The objective of this work is to compare the effectiveness of mixed crude enzyme cellulase from T. reesei and A. niger with commercial enzyme from A. niger, and to investigate effect of enzyme to substrate ratio to performance of enzymatic hydrolysis of rice straw. The commercial enzyme from Fluka Biochemica was used, and crude enzyme were prepared by solid fermentation with simple media. Before hydrolized, the rice straw was grinded and sieved and then heated at 85 o C with 2% sodium hydroxide for six hours. Hydrolysis was conducted in 300 mL beaker flask equipped with mechanical stirrer. Samples were analyzed by dinitrosalicylic acid method and measured by spectrophotometer. Both of commercial and mixed crude enzyme show that, the higher enzyme to substrate ratio was higher the glucose concentration obtained. However, ratio of glucose obtained to enzyme used become smaller. The mixture of crude enzyme from T. reesesi dan A. niger that produced in this work was two fold more effective to hydrolyze rice straw than using cellulase enzyme of A. niger from Fluka Biochemika
Development of a Novel Support Modification for Efficient Lipase Immobilization: Preparation, Characterization, and Application for Bio-flavor Production Moentamaria, Dwina; Irfin, Zakijah; Chumaidi, Achmad; Widjaja, Arief; Widjaja, Tri; Muharja, Maktum; Darmayanti, Rizki Fitria
Bulletin of Chemical Reaction Engineering & Catalysis 2024: BCREC Volume 19 Issue 2 Year 2024 (August 2024)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.20130

Abstract

The low cost and excellent catalytic properties of lipase for industrial processes are highly desirable. A promising new approach involves the support modification of lipase and spacer arm, which enables the enhancement of lipase properties. This study investigates the immobilization of crude lipase from Mucor miehei onto a Polyurethane Foam (PUF) surface using various coating techniques. The PUF matrix was obtained through isocyanate and polyol reactions. Subsequently, the PUF was coated by adsorbing lipase and adding edible support material. The immobilized lipase was then utilized in the hydrolysis of coconut oil to produce fatty acids. Furthermore, the immobilized enzyme was employed in the esterification of fatty acids to produce bio-flavors. The results demonstrate that the attachment reaction using support material, namely lecithin, gelatin, MgCl2, and Polyethylene glycol 6000 (PEG), all of which are simple and edible, was able to enhance the stability and reusability of lipase. This immobilization technique increased triglyceride hydrolysis into FFA by 422%. The successful edible support modification of immobilized lipase from M. miehei on PUF, coupled with significantly enhanced enzyme stability and catalytic activity, offers a promising, environmentally friendly solution for diverse applications in the food industry. Copyright © 2024 by Authors, Published by BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).
Co-Authors Achmad Chumaidi, Achmad Achmad Zubaydi Adi Soeprijanto Aditya Dwi Saputra Adrian Nur Adrian Nur Afan Hamzah, Afan Agra Bachtiar Ahmad Zubaydi Akbarningrum Fatmawati Akbarningrum Fatmawati Akhmad Basuki Widodo Al-Ghifari, Admiral Yagi Anwar, Nadiem Aparamarta, Hakun Wirawasista Aparamarta, Hakun Wirawista Apol, Tabina Raissa Ari Anggoro Arif , Irfan Syarief Artaraharja, Yoseph Daniswara Bagiyo Suwasono Bagiyo Suwasono Bagiyo Suwasono Bagiyo Suwasono, Bagiyo Baiq Firyal Salsabilla Safitri Candra Wijaya, Candra Debra Arlin Puspasari Debra Arlin Puspasari Denistira Fazlur Rahman Desi Liah Martasari Desy Nurwijayanti Dwina Moentamaria Eny Setyowati F Ferry Fadilah, Siska Nuri Firmansyah, Arfian Alwi Fredi Susanto Hanny F. Sangian Hasanudin Hellen Kartika Dewi Hellen Kartika Dewi Hermawan, Yuda Apri Heru Setyawan I Nyoman Budiantara I. Wuled Lenggoro Ilham Alamsah Ilham Alamsyah Integrity, Justian Immanuel Irfan Albana Irfin, Zakijah Irma Nurhanifah Fenda Putri Jayyid Zuhdan Junaidi Kristian Junaidy Kristian Junaidy Kristian Junianti, Fitri Kamila Adila Muslim Karima, Nur Kurniawan Candra Eka Prasetya Mamuji Putra Laila Nur Rahmah Laila Nur Rahmah Lidya Lorenta Sitompul Lieke Riadi M Musmariadi M. Rasyid, Daniel M. Zaed Yuliadi Ma'ruf, Buana Marcus Tukan Maulidarsyah, Muhammad Fauzan Muhammad Nurul Hakim Muharja, Maktum Mukti Mulyawan Nadiem Anwar Novandira, Belva Angeline Nur Fadhilah Nur Fadhilah Nurkhamidah , Siti Nurul Maziyah Nurul Maziyah Panunggal, Eko Patdono Suwignjo Pertiwi, Urania Noor Lintang Rachma, Fanina Aulia Ratna Purwaningsih Ratna Purwaningsih Ratna Purwaningsih Rizki Fitria Darmayanti Rohmah, Ika Putri Nikmatur Samsudin Affandi Sangadji, Ningsi Lick Setiyo Gunawan Silvya Yusnica Agnesty Silvya Yusnica Agnesty Silvya Yusnica Agnesty Silvya Yusnica Agnesty Siska Nuri Fadilah Siska Nuri Fadilah Soedarmodjo, Thea Prastiwi Soegiono, Soegiono Sri Gunani Partiwi Sri Gunani Partiwi Sugeng Winardi Sukma Rahma Sukma Rahma Sukmawati Rahma Tantular Nurtono Thea Prastiwi Soedarmodjo Tri Achmadi Tri Widjaja Winardi, Sugeng Yakub Hendrikson Manurung Yakub Hendrikson Manurung Yuliadi, M. Zaed Zaed Yuliadi Zaed Yuliadi, Zaed Zubaydi, Ahmad Zuhroh, Saiyyidah Tus