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"Sektor energi menjadi penyumbang 75% emisi gas rumah kaca yang dilaporkan oleh International Energy Agency tahun 2021. Oleh karena itu, transisi penggunaan energi fosil ke energi alternatif, salah satunya energi hidrogen (H2), harus diimplementasikan lebih luas lagi terutama terhadap kedua sektor tersebut untuk mengurangi emisi gas rumah kaca. Penelitian ini bertujuan untuk mengembangkan katalis berbasis tembaga (Cu) yang tinggi aktivitas katalitiknya pada reaksi methanol steam reforming (MSR) untuk memproduksi H2. Pemilihan support yang baik penting untuk performa katalis Cu. Dalam penelitian ini, Ce diperkenalkan sebagai dopan Zr pada sistem support CaZrO3. CeO2 dikenal sebagai support sekaligus promoter yang baik karena karakteristik oxygen storage capacity (OSC) yang tinggi sehingga dapat meningkatkan aktivitas katalitik Cu/CaCe(x)Zr(1-x)O3. Cu/CaCe(x)Zr(1-x)O3 disintesis dengan metode sol-gel dan dry impregnation dan diuji aktivitasnya pada reaksi MSR pada 250, 300, dan 350 °C. Komposisi Ce-Zr dan variabel temperatur dievaluasi pada penelitian ini. Cu/CaCe(x)Zr(1-x)O3 dikarakterisasi dengan XRF, XRD, Spektroskopi Raman, SAA, O2-TPO, dan TEM. Hasilnya, variasi rasio Ce-Zr telah sesuai dengan yang diharapkan, Cu telah berhasil diimpregnasi ke permukaan support, kelima katalis adalah material mesopori, dan Cu/CaCeO3 diketahui memiliki densitas oxygen vacancy (Ovac) tertinggi, yang menandakan OSC yang juga tinggi. Sesuai dengan perolehan densitas Ovac tertinggi, Cu/CaCeO3 unggul dalam uji reaksi MSR di ketiga temperatur uji, dengan konversi metanol, yield H2, dan produksi H2 pada temperatur tertinggi berturut-turut sebesar 98,37%, 86,59%, dan 0,0539 mol/min/gcat.

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The energy sector accounted for 75% of greenhouse gas emissions reported by the International Energy Agency in 2021. Therefore, the transition from fossil fuels to alternative energy sources, one of which is hydrogen (H₂) energy, must be widely implemented especially in those two sectors to reduce greenhouse gas emissions. This research aims to develop a copper (Cu)-based catalyst with high catalytic activity in the methanol steam reforming (MSR) reaction for H2 production. The selection of a suitable support is crucial for the performance of the Cu-based catalysts. In this study, Ce is introduced as a dopant in Zr within the CaZrO3 support system. CeO₂ is well-known to be an excellent support and promoter due to its high oxygen storage capacity (OSC) characteristic, which can enhance the catalytic activity of Cu/CaCe(x)Zr(1-x)O3. Cu/CaCe(x)Zr(1-x)O3 was synthesized using sol-gel and dry impregnation methods and tested for activity in the MSR reaction at temperatures of 250, 300, and 350 °C. The Ce-Zr composition and temperature variables are evaluated in this study. Cu/CaCe(x)Zr(1-x)O3 was characterized using XRF, XRD, Raman spectroscopy, SAA, O2-TPO, dan TEM. The results indicate that the desired and obtained ratios of the catalyst are in agreement with one another, Cu is successfully impregnated onto the surface of CaCe(x)Zr(1-x)O3, all five catalysts are mesoporous materials, and Cu/CaCeO3 exhibits the highest density of oxygen vacancies (Ovac), indicating a high OSC. Consistent with the highest Ovac density obtained, Cu/CaCeO3 excels in MSR reaction tests at all three test temperatures, with methanol conversion, H₂ yield, and H₂ production at the highest temperature being 98,37%, 86,59%, dan 0,0539 mol/min/gcat."

"Metanol dianggap sebagai pembawa hidrogen yang menjanjikan karena kemampuannya untuk melepaskan hidrogen. Katalis berbasis tembaga umumnya digunakan memiliki stabilitas termal rendah di atas ambang batas keamanan. Platinum dapat memfasilitasi dispersi nanopartikel tembaga, mencegah aglomerasi, dan memastikan distribusi seragam pada permukaan katalis, meningkatkan aksesibilitas dan reaktivitas situs aktif tembaga. Penelitian ini mengeksplorasi penggunaan katalis bimetal tembaga-platinum sebagai peningkatan stabilitas katalis penyangga Ca(Ce0.5Zr0.5)O3 pada reaksi methanol steam reforming. Penggunaan support perovskite Ca(Ce0.5Zr0.5)O3 memberikan potensi peningkatan laju reaksi pada water-gas shift reaction dalam reaksi methanol steam reforming. Karakterisasi katalis dilakukan dengan menggunakan XRD, XRF, SAA, Spektroskopi Raman, dan TEM. Aktivitas katalitik pada reaksi methanol steam reforming diuji dengan adanya variasi komposisi dan temperatur. Katalis Cu0.75Pt0.25/Ca(Ce0.5Zr0.5)O3 memiliki aktivitas katalitik tertinggi dengan menghasilkan konsentrasi hidrogen sebesar 24,15% dan produksi hidrogen sebesar 0,0069 mol/min/g. Didapatkan temperatur yang optimal dengan aktivitas katalitik yang baik, yaitu temperatur 350ºC.

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Methanol is considered a promising hydrogen carrier due to its ability to release hydrogen. Commonly used copper-based catalysts have low thermal stability above the safety threshold. Platinum can facilitate the dispersion of copper nanoparticles, prevent agglomeration, and ensure uniform distribution on the catalyst surface, improving the accessibility and reactivity of copper active sites. This study explores the use of platinumcopper bimetal catalysts as an improvement in the stability of the Ca(Ce0.5Zr0.5)O3 support catalyst in the methanol steam reforming reaction. The use of perovskite support Ca(Ce0.5Zr0.5)O3 provides the potential for increasing the reaction rate in the water-gas shift reaction in the methanol steam reforming reaction. Catalyst characterization was carried out using XRD, XRF, SAA, Raman spectroscopy, and TEM. Catalytic activity in the methanol steam reforming reaction was tested in the presence of composition and temperature variations. Cu0.75Pt0.25/Ca(Ce0.5Zr0.5)O3 catalyst has the highest catalytic activity by producing hydrogen concentration of 24.15% and hydrogen production of 0.0069 mol/min/g. The optimal temperature with a good catalytic activity is 350ºC."

"The effect of hydrogen and hydrides on the integrity of zirconium alloy components : delayed hydride cracking provides a detailed explanation focusing on the properties of hydrogen and hydrides in these alloys. Whilst the emphasis lies on zirconium alloys, the combination of both the empirical and mechanistic approaches creates a solid understanding that can also be applied to other hydride forming metals. This up-to-date reference focuses on documented research surrounding DHC, including current methodologies for design and assessment of the results of periodic in-service inspections of pressure tubes in nuclear reactors. Emphasis is placed on showing how our understanding of DHC is supported by progress in general understanding of such broad fields as the study of hysteresis associated with first order phase transformations, phase relationships in coherent crystalline metallic solids, the physics of point and line defects, diffusion of substitutional and interstitial atoms in crystalline solids, and continuum fracture and solid mechanics. Furthermore, an account of current methodologies is given illustrating how such understanding of hydrogen, hydrides and DHC in zirconium alloys underpins these methodologies for assessments of real life cases in the Canadian nuclear industry."

"ABSTRACTPenanganan gas karbon dioksida CO2 buangan pembangkit listrik tenaga batubara dapat dilakukan dengan menggunakan teknologi Carbon Capture and Sequestration CCS melalui penangkapan CO2. CO2 yang telah ditangkap dari pembangkit dapat dikonversi menjadi produk kimia. Penelitian bertujuan mendapatkan kinerja teknis dan kelayakan ekonomi dari proses terintegrasi Carbon Capture dengan sintesis olefin menggunakan CO2 hasil penangkapan dan hidrogen terbarukan. Dilakukan simulasi terhadap 2 skema proses terintegrasi, yaitu produksi olefin dari CO2 hasil CCS dengan menggunakan hidrogen terbarukan dari elektrolisis air dan gasifikasi biomassa. Simulasi dilakukan dengan UniSim Design dan Aspen. Dari hasil simulasi tersebut dianalisis kinerja teknisnya dan secara ekonomi menggunakan metode levelized cost. Hasil penelitian ini diperoleh bahwa proses terintegrasi CCS dengan produksi olefin menggunakan hidrogen terbarukan dari elektrolisis air memiliki intensitas energi termal dan CO2 abatement yang paling baik 123.21 GJ/ton olefin dan 79.3 sedangkan proses terinetgrasi CCS dengan produksi olefin menggunakan hidrogen terbarukan dari gasifikasi biomassa memiliki intensitas energi listrik dan biaya produksi yang paling baik 32.29 MWh/ton olefin dan 3,064.43 /ton olefin.

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ABSTRACTHandling of exhaust gases from coal based power plant can be done using Carbon Capture and Sequestration CCS technology by installing additional equipment for the capture of CO2. CO2 that has been captured from the plant can be converted into a product. The goal of this research is to obtain the technical performance and economical feasibility of an integrated process of CCS with olefin synthesis using renewable hydrogen. In this research, simulations are done to 2 integrated process scheme, which is olefin production using captured CO2 through renewable hydrogen from water electrolysis and biomass gasification using UniSim Design and Aspen Plus simulators. These schemes rsquo technical performance will be analyzed which is its energy intensity, CO2 abatement, and whole energy usage. These schemes will also be analyzed economically using levelized cost analysis method. It is found that olefin production using captured CO2 through renewable hydrogen from water electrolysis has the best thermal energy intensity and CO2 abatement 123.21 GJ ton olefin 79.3 whereas olefin production using captured CO2 through renewable hydrogen from biomass gasification has the best electrical energy intensity and has the lowest levelized cost value 32.29 MWh ton olefin 3,064.43 ton olefin."

"Eritropoietin (EPO) adalah hormon glikoprotein yang terdiri dari 165 asam amino dan memiliki berat molekul sebesar 30.400 Daltons. Sebagian besar kebutuhan EPO didapatkan dari hasil sintesis pada selmamalia Chinese hamster ovary (CHO). Pichia pastoris adalah sejenis khamir yang populer digunakan untuk menggantikan sistem ekspresi pada sel mamalia. P. pastoris dapat menggunakan metanol sebagai satu-satunya sumber energi karbon. Pada studi ini, protein rekombinan EPO (rhEPO) disintesis dengan cara mengekspresikan gen hEPO pada khamir metilotropik P. pastoris strain X33. Studi ini dilakukan untuk mengetahui konsentrasi metanol dan waktuinkubasi yang optimal untuk mensintesis rhEPO. Pada studi ini konsentrasi metanol yang digunakan adalah 0%, 0.5%, 1%, 2.5%, 5%, 10%, dan 20%. Sedangkan waktu inkubasi yang digunakan adalah 0 jam, 24 jam, 48 jam, 72 jam, 96 jam, 120 jam, and 144 jam. Hasil penelitian ini menunjukkan bahwa ekspresi protein yang tertinggi terjadi padakonsentrasi metanol sebesar 2.5% dan waktu inkubasi selama 48 jam.

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AbstractErythropoietin (EPO) is a glycoprotein hormone consists of 165 amino acids and has molecular mass of 30,400 Daltons. The large quantities of these hormone required to satisfy clinical demand are currently met by recombinant expression in mammalian cell, namely chinese hamster ovary (CHO). Pichia pastoris has become popular yeast based proteinproduction systems to substitute mammalian expression systems.P. pastoris is capable to use methanol as sole carbon and energy source. In this study, recombinant human EPO (rhEPO) protein obtained by expressing the hEPO gene in methylotropic yeastP. pastoris, strain X33. The present work was carried out to study the optimal methanol concentration for induction and the incubation time to obtain rhEPO protein. To perform this study, the transformedP. pastoris was induced with various concentrations of methanol (0%, 0.5%, 1%, 2.5%, 5%, 10%, and 20%) and incubation times (0 hours, 24 hours, 48 hours, 72 hours, 96 hours, 120 hours, and 144 hours). The results demonstrate that the highest protein expression level occurred at concentration of 2.5% methanol induction, while the optimal incubation time was at 48 hrs. "

"Penelitian ini bertujuan untuk memproduksi hidrogen melalui proses steam reforming bio-oil dari tandan kosong kelapa sawit dengan katalis Ni-Ce/La2O3-γAl2O3. Penelitian ini menggunakan variasi rasio cerium terhadap nikel (Ce/Ni) pada katalis, yaitu sebesar 0,25; 0,5; 0,75; dan 1,00. Steam reforming dilakukan dengan fixed bed reactor pada suhu 700oC dengan tekanan atmosferik. Bio-oil yang digunakan merupakan bio-oil aqueous fraction dengan rumus empirik CH1,47O0,27. Senyawa yang paling banyak dikandung dalam bio-oil yang digunakan adalah asam asetat dan fenol. Hasil penelitian menunjukkan bahwa katalis Ni-0,25Ce mampu menghasilkan yield hidrogen tertinggi dan karbon terdeposisi terendah. Yield hidrogen tertinggi yang dicapai katalis Ni-0,25Ce adalah 18,53% pada menit ke-10 sedangkan karbon terdeposisi yang dicapai katalis Ni-0,25Ce adalah sebesar 0,0959 gram. Semakin banyak loading cerium dari suatu katalis akan mengurangi yield hidrogen karena luas permukaan inti aktif semakin berkurang karena dispersi nikel yang rendah.

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This research has a purpose to produce hydrogen by steam reforming of bio-oil from empty fruit bunch with Ni-Ce/La2O3- γAl2O3 catalyst. Variation used in this research is cerium to nickel ratio (Ce/Ni) = 0,25; 0,5; 0,75; dan 1,00. Steam reforming is operated in a fixed bed reactor with 700oC temperature and atmospheric condition. Bio-oil used is bio-oil aqueous fraction with CH1,47O0,27 as its empirical formula. Major components contained inside bio-oil aqueous fraction are acetic acid and phenol. The results of this research shows that Ni-0,25Ce catalyst can produce hidghest hydrogen yield until 18.53% in minute 10. Moreover, deposited carbon resulted by Ni-0,25Ce is 0.0959 gram. The more cerium contained in a catalyst can lead to the decreasing of hydrogen production due to the decreasing of specific surface area because of low disperse of nickel."

"This research has the effort to develop catalyst for steam reforming of bio oil. The bio oil is liquidproduct that iv produced _from biomass pyrolysis. The reforming of bio oil produces hydrogen gas. The mainchallenge in reforming of organic compound especially aromatic, in bio oil as phenol, is carbon formationat the catalyst surface resulted in uncomplete reaction. The catalyst formulation resulted is expected to havehigh resistance to catalyst deactivation because of carbon formation. Beside that, it is expected too to havehigh stability and activity, compared to commercial nickel based catalyst. For those purposes, research ofsteam reforming of m-cresol in bench scale has been done. m-cresol is one of phenol compounds in bio oil,that has stable properties, difficult to react and disturb the catalyst activity. The catalyst formulation used isRu-Ni/MgO.La;O3.Al2O3 mixture. This research has succeed to develop catalyst of reforming from Ni-Rumetal combination that having the good stability and activity to reform m-cresol. The best catalystcomposition resulted is 2%Ru-15%Ni. In Ni and Ru catalyst combination, Ni catalyst is the mainly activecomponent in reforming of oxygenated aromatic compound in bio oil The Ru catalyst function is to increaseNi metal dispersion on support, by then increasing the catalyst stability."

"Analisis tekno-ekonomi dilakukan untuk proses ko-elektrolisis menggunakan sel elektroliser oksida padat di dalam pembangkit Power-to-Methanol di Indonesia. Proses yang diusulkan disimulasikan menggunakan Unisim dan Microsoft Excel. Perangkat lunak Unisim digunakan untuk simulasi Power-to-Methanol termasuk ko-elektrolisis dan sintesis metanol. Sedangkan excel digunakan untuk menghitung variabel penting lainnya yang tidak dapat dihitung di Unisim. Kapasitas produksi metanol 3764 MT/tahun dan Rasio SN 2.15 pertama-tama ditentukan, diikuti dengan pembuatan simulasi dan integrasi. Selanjutnya, hasil perhitungan kondisi operasi Ko-elektrolisis jika diterapkan di pabrik PtM dievaluasi. Langkah terakhir dilakukan dengan menganalisis dan mengevaluasi pengaruh harga jual metanol terhadap beberapa variabel dan skenario. Hasil penelitian menunjukkan bahwa kondisi operasi ko-elektrolisis ideal untuk aplikasi PtM dengan daya elektrolisis dan panas proses masing-masing 3700 kW dan 7073 kW. Aplikasi ko-elektrolisis SOEC di PtM juga mampu mencapai kondisi tegangan termal-netral yang diinginkan. Penilaian ekonomi menunjukkan bahwa CAPEX dan OPEX dalam penelitian ini adalah 3 kali dan 2 kali lebih tinggi dari benchmark pabrik e-metanol lainnya. Harga produksi e-metanol dalam penelitian ini adalah $1094/MT. Skenario yang paling mungkin terjadi yaitu skenario realistis (2 dan 3), menunjukkan bahwa harga jual e-metanol yang menguntungkan untuk mencapai payback period tidak lebih dari 10 tahun adalah $1200-1400/MT.

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Techno-economic analysis was performed for a co-electrolysis process using solid oxide electrolyzer cell inside a power-to-methanol plant in Indonesia. The proposed process was simulated using Unisim and Microsoft Excel. Unisim software is used for the power to methanol plant simulation including co-electrolysis and methanol synthesis. While the excel is used to calculate other important variables that can’t be calculated in Unisim. The methanol production capacity of 3764 MT/year and SN Ratio of 2.15 is first to be determined, followed with the simulation modelling and integration. Subsequently, the co-electrolysis operating condition calculation result if applied in PtM plant is evaluated. The last step is done by analysing and evaluating methanol selling price effect upon several variables and scenarios. The result shows that the co-electrolysis operating condition is ideal for PtM application with the electrolysis power and process heat of 3700 kW and 7073 kW correspondingly. The SOEC co-electrolysis application in PtM is also able to achieve the desired thermal-neutral voltage condition. The economic assessment shows that the CAPEX and OPEX in this research is 3 times and 2 times higher than the other e-methanol plant benchmarks. The e-methanol production price in this research is $1094/MT. The most possible occurring scenario which is the realistic scenario (2 and 3) shows that the profitable e-methanol selling price to achieve not more than 10 years payback period is at $1200-1400/MT."

"Laju penguapan semprotan bahan bakar pada motor pembakaran dalam mempunyai peran yang sangat penting dalam kesempurnaan pembakaran. Semprotan ini berbentuk seperti tetesan-tetesan bahan bakar yang sangat kecil. Tevfik Gemci et. al. telah melakukan simulasi semprotan cairan dengan perangkat lunak KIVA-3V. Beberapa perangkat lunak simulasi pembakaran, seperti KIVA-3V dan Fluent, menggunakan model analogi Ranz-Marshall dan stagnan film untuk menghitung laju perpindahan massa dan panas. Penelitian ini bertujuan untuk melihat kesesuaian kombinasi kedua model tersebut yang diterapkan pada tetesan metanol (𝐿𝑒=1,5) dengan data eksperimen. Selain itu, penelitian ini juga bertujuan untuk membandingkan model Ranz-Marshall dan stagnan film dengan kombinasi model yang diusulkan oleh Kosasih E.A. dan Alhamid M.I (modifikasi stagnan film). Setelah dianalis, besar Sh dan Nu yang dihasilkan model Ranz-Marshall memiliki korelasi yang buruk dengan yang dihasilkan model stagnan film dan modifikasi. Oleh karena itu, makalah ini juga membahas koreksi terhadap koefisien C1 dan C2 yang digunakan dalam model modifikasi stagnan film.

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Fuel spray evaporation rate in inner combustion engine has an important role in the perfection of combustion. The spray consists of small dropplets of fuel. Tevfik Gemci et. al. had worked on simulation of spray with KIVA-3V software. Some combustion simulation software, such as KIVA-3V and Fluent, use Ranz-Marshall analog model and stagnant film model to calculate heat and mass transfer rate. This study is aimed to show the correlation between the two models on methanol droplet evaporation (𝐿𝑒=1,5) using experimental data. Besides, this study is also intended to compare stagnan film and Ranz-Marshall analog model to the combination of the two models (modified stagnan film) which Kosasih E.A and Alhamid M.I had proposed. After it was analysed, it was found that the result of Sh dan Nu using Ranz-Marshall analog model has a bad correlation to stagnan film and modification model. Thus, this paper also discusses a correction on C1 and C2 coefficient which is used in modification model."

"Laju penguapan semprotan bahan bakar pada motor pembakaran dalam mempunyai peran yang sangat penting dalam kesempurnaan pembakaran. Semprotan ini berbentuk seperti tetesan-tetesan bahan bakar yang sangat kecil. Tevfik Gemci et. al. telah melakukan simulasi semprotan cairan dengan perangkat lunak KIVA-3V. Beberapa perangkat lunak simulasi pembakaran, seperti KIVA-3V dan Fluent, menggunakan model analogi Ranz-Marshall dan stagnan film untuk menghitung laju perpindahan massa dan panas. Penelitian ini bertujuan untuk melihat kesesuaian kombinasi kedua model tersebut yang diterapkan pada tetesan metanol (Le=1,5) dengan data eksperimen. Analisa yang dilakukan menunjukkan bahwa besar Sh dan Nu model stagnan film memiliki korelasi yang lemah terhadap model analogi Ranz-Marshall.

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Fuel spray evaporation rate in inner combustion engine has an important role in the perfection of combustion. The spray consists of small dropplets of fuel. Tevfik Gemci et. al. had worked on simulation of spray with KIVA-3V software. Some combustion simulation software, such as KIVA-3V and Fluent, use Ranz-Marshall analog model and stagnant film model to calculate heat and mass transfer rate. This study is aimed to show the correlation between the two models on methanol droplet evaporation (Le=1,5) using experimental data. Besides, this study is also intended to compare stagnan film and Ranz-Marshall analog model to the combination of the two models (modified stagnan film) which Kosasih E.A and Alhamid M.I had proposed. After it was analysed, it was found that the result of Sh dan Nu using Ranz-Marshall analog model has a bad correlation to stagnan film."