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The Impact of Varying Mixing Rates in a Surfactant-Free Fuel Emulsion Mixer on the Efficiency and Emissions of a Diesel Engine Santoso, Budi; Sartomo, Agus; Ubaidillah, Ubaidillah; Muraza, Oki; Maharani, Elliza Tri
Automotive Experiences Vol 7 No 1 (2024)
Publisher : Automotive Laboratory of Universitas Muhammadiyah Magelang in collaboration with Association of Indonesian Vocational Educators (AIVE)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31603/ae.10907

Abstract

The research focuses on water diesel emulsion (WDE), a topic that has captivated researchers for an extended period. While previous studies predominantly employed surfactants to enhance mixing efficiency, their non-economic feasibility in transportation logistics has prompted a shift in recent investigations. This study presents experiments utilizing a cost-effective WDE comprising 15% water and a mixer devoid of surfactants to investigate the impact of mixer blade rotation on engine performance, fuel consumption, and NOx emissions. NOx emission tests were conducted under a constant engine speed of 2,000 rpm and a 75% load (3,23 kW). The optimal brake-specific fuel consumption (BSFC) for the 15% WDE fuel occurred at a blade rotation speed of 3,000 rpm, resulting in a 1% power reduction (from 4,41 kW to 4,38 kW), a 13.3% decrease in BSFC (from 694,98 gr/kW.h to 602,52 gr/kW.h), and a 30% reduction in NOx emissions (from 54 ppm to 38 ppm). This discovery holds promise for future advancements in green energy applications within the transportation sector.
Effect of Ammonia, Urea, and Magnesium Modification on γ-Al2O3 Support in Enhancing the Catalytic Performance for Hydrodemetallization and Hydrodesulfurization Rustyawan, Wawan; Makertihartha, I. G. B. N.; Muraza, Oki; Gamar, Ismal; Nurdini, Nadya; Kadja, Grandprix T.M.; Rasrenda, Carolus B.
Bulletin of Chemical Reaction Engineering & Catalysis 2025: BCREC Volume 20 Issue 2 Year 2025 (August 2025)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.20360

Abstract

This research investigates the modification of γ−Al₂O₃ using ammonia, urea, and magnesium acetate to enhance its catalytic properties for hydrodemetallization (HDM) and hydrodesulfurization (HDS). Structural modifications affected the mineral composition, crystal size distribution, and textural properties of the support, with boehmite crystal sizes consistently ranging from 7 to 10 nm. Textural analysis indicated that alumina supports modified with urea and ammonia demonstrated enhanced characteristics, including elevated specific surface area (SBET), pore volume (VT), and pore size distribution (d), which are essential for catalytic performance. The modified catalyst (HM) exhibited significant hydrodemetalation efficiency, attaining metal removal rates of 98% for iron, 71% for vanadium, and 99% for nickel. In the HDS reaction, HM demonstrated the highest sulfur conversion of 20.9% at 315 °C, due to its capacity to sustain active site availability. The primary cause of catalyst deactivation was metal deposition, which resulted in pore blockage and diminished efficiency. The findings underscore the importance of support modification in enhancing catalytic performance, indicating HM as a viable catalyst for future heavy oil refining applications. Copyright © 2025 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).
Perengkahan n-Butana Menggunakan Katalis Nanopartikel Zeolit Alam Klaten Kurniawan, Teguh; Muraza, Oki
Jurnal Rekayasa Kimia & Lingkungan Vol 13, No 2 (2018): Jurnal Rekayasa Kimia & Lingkungan (December, 2018)
Publisher : Chemical Engineering Department, Syiah Kuala University, Banda Aceh, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23955/rkl.v13i2.12059

Abstract

Increasing demand on olefins, high energy consumption of thermal cracking and oil depletion are the driving force to find new process to produce olefins. Catalytic cracking of n-butane is promising route to produce olefins. In this paper, we synthesized nanoparticle from natural zeolites by ball milling-recrystallization method and studied the effect of acid dealumination over the nanozeolites on the catalytic properties. Particle size was evaluated visually by using scanning electron microscope. X-Ray Diffraction analysis was performed to study zeolites phase and its crystallinity. Acid dealumination effect over nanosized mordenite on the acidity were evaluated by ammonia TPD and pyridine FTIR. Textural properties of zeolites were characterized by nitrogen physisorption at -196 oC. The catalysts were tested in a fixed bed reactor for n-butane cracking to olefins product. Various temperature conditions were applied ranging from 350 oC to 650 oC for n-butane cracking in a fixed bed reactor. Conversions of n-butane were 15% and 90% at 350 oC and 650 oC, respectively. Selectivity to olefins was increase from 1% at 350 oC to 47% at 650 oC.