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"Penelitian ini bertujuan memanfaatkan kalsium oksida (CaO) dari pasir kuarsa Lombok sebagai katalis pada sintesis aviation fuel melalui proses pirolisis limbah ban. Tiga variasi utama dilakukan, yaitu variasi persen berat katalis (1 wt%, 3 wt%, dan 5 wt%), proses treatment terhadap pasir Pantai Pink, serta perbandingan sumber pasir (Pantai Pink, Tanjung Aan, Kuta Mandalika, dan CaO analitik). Penelitian ini menguji beberapa parameter, termasuk uji GC-MS, uji FTIR, uji XRD, uji BET, uji XRF, uji SEM-EDX, densitas, dan viskositas. Hasil menunjukkan bahwa katalis CaO dari pasir pantai Lombok berhasil berpengaruh terhadap perubahan sifat fisik dan kimia aviation fuel yang dibuktikan dengan uji BET dimana luas permukaan spesifik tinggi (368,927 m²/g), uji SEM-EDX dimana permukaan partikel yang tidak beraturan dan berpori yang menujukkan luas permukaan katalis besar dan dapat mengidentifikasi Ca (42,1% weight) dan O (57,4% weight) sebagai unsur dominan,  uji XRF yang mendapatkan kandungan (CaO) dengan konsentrasi sangat tinggi yaitu 89,919%. dan XRD yang menunjukkan puncak khas CaO pada 2θ = 37,37°, yang sesuai dengan karakteristik kristal kalsium oksida (CaO). Meski demikian, aviation fuel yang dihasilkan masih belum memenuhi standar Jet A/A-1 karena densitas yang didapatkan aviation fuel sekitar 892–909,38 kg/m³ dan viskositas sekitar 2,406–2,804 mm²/s masih di tidak sesuai standar, yaitu pada densitas (775–840 kg/m³) dan viskositas (idealnya 1,3–1,9 mm²/s pada 40 °C). Temuan ini menunjukkan bahwa pasir pantai Lombok memiliki potensi kuat sebagai katalis pada proses pirolisis limbah ban, namun masih perlu dilakukannya proses upgrading lanjutan terhadap aviation fuel hasil pirolisis, guna menurunkan densitas dan viskositas agar sesuai dengan standar Jet A/Jet A-1. Penelitian ini diharapkan memberikan hasil yang komprehensif dalam skala laboratorium dan berkontribusi pada pengembangan teknologi pembuatan aviation fuel dari limbah ban menggunakan katalis kalsium oksida.

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This study aims to utilize calcium oxide (CaO) from Lombok quartz sand as a catalyst in the synthesis of aviation fuel through the pyrolysis process of waste tires. Three main variations were conducted, namely the weight percent variation of the catalyst (1 wt%, 3 wt%, and 5 wt%), the treatment process of Pink Beach sand, and the comparison of sand sources (Pink Beach, Tanjung Aan, Kuta Mandalika, and analytical CaO). This study tested several parameters, including GC-MS test, FTIR test, XRD test, BET test, XRF test, SEM-EDX test, density, and viscosity. The results showed that the CaO catalyst from Lombok beach sand successfully influenced the changes in the physical and chemical properties of aviation fuel as evidenced by BET test where the specific surface area was high (368.927 m²/g), SEM-EDX test where the irregular and porous particle surface indicated a large catalyst surface area and could identify Ca (42.1% weight) and O (57.4% weight) as the dominant elements, XRF test which obtained a very high concentration of (CaO) of 89.919%. and XRD which showed a typical CaO peak at 2θ = 37.37°, which is consistent with the crystalline characteristics of calcium oxide (CaO). However, the aviation fuel produced still does not meet the Jet A/A-1 standard because the density obtained by the aviation fuel is around 892-909.38 kg/m³ and the viscosity is around 2.406-2.804 mm²/s which is still not in accordance with the standard, which is in density (775-840 kg/m³) and viscosity (ideally 1.3-1.9 mm²/s at 40 °C). These findings indicate that Lombok beach sand has strong potential as a catalyst in the pyrolysis process of waste tires, but there is still a need for further upgrading of the pyrolyzed aviation fuel, in order to reduce density and viscosity to comply with Jet A/Jet A-1 standards. This research is expected to provide comprehensive results on a laboratory scale and contribute to the development of aviation fuel production technology from waste tires using calcium oxide catalyst."

"Saat ini ada kendala dalam pengadaan semen khusus yang sesuai untuk dijadikan bahan penyekat sumur injeksi CO2 pada Carbon Capture and Storage (CCS). Semen Kelas-G merupakan bahan dasar yang dapat dimodifikasi sehingga sesuai untuk penggunaan pada sumur injeksi CO2 di mana dalam bentuk suspensi semen dan air banyak digunakan untuk penyekat ruang anulus pada sumur minyak dan gas bumi. Suspensi semen berbahan semen Kelas-G mengalami penyusutan volume selama proses pengerasan. Hal ini merupakan salah satu kekurangan semen Kelas-G jika diaplikasikan tanpa modifikasi. Selain itu semen Kelas-G cenderung terdegradasi apabila berada di lingkungan air dengan kandungan CO2 tinggi. Pada penelitian ini, semen Kelas-G dimodifikasi dengan menambahkan aditif mengembang (swelling) CaO dan MgO untuk mengatasi penyusutan volume dan degradasi tersebut. Selain itu, silica flour sebagai supplementary cementitious material dipergunakan juga dengan komposisi 35% by weight of cement (BWOC) sebelum ditambahkannya aditif tersebut. Penelitian ini bertujuan untuk meneliti dampak penambahan aditif tersebut di atas terhadap perubahan ketahanan korosi dan kekuatan mekanik suspensi semen di lingkungan air dengan kandungan CO2 tinggi. Pembuatan sampel dilakukan di laboratorium dengan variasi komposisi aditif (5%, 10%, 15%, dan 20% BWOC) temperatur cure (26°C dan 50°C) dan waktu cure sebelum uji korosi (1 hari dan 7 hari). Untuk mensimulasikan kondisi air dengan kandungan CO2 tinggi, sampel dibenamkan di dalam air tersaturasi CO2 di dalam autoclave bertekanan 2,0684 MPa dan temperatur 50°C selama 14 hari. Selain uji korosi, dilakukan juga pengujian X-Ray Diffraction, Scanning Electron Microscopy/Energy-Disperse X-ray Spectroscopy, Scanning Electron Microscopy, Laser Particle Size Analyzer, Uniaxial Expansive/Shrinkage, Ultrasonic Cement Analyser, Three Point Bending Test, dan Macro Photo Imaging. Hasil percobaan menunjukkan bahwa penambahan aditif CaO (komposisi 5%, 10%, 15%, dan 20% BWOC) dan MgO 20% BWOC dapat mencegah penyusutan volume pada suspensi semen Kelas-G. Peningkatan ketahanan korosi tertinggi terjadi pada sampel SC15(1d-26C) yakni sebesar 70,50%. Peningkatan kekuatan mekanik tertinggi terjadi pada sampel SC5(1d-50C) yakni sebesar 43,82%. Peningkatan ketahanan korosi tertinggi akibat penambahan aditif MgO terjadi pada SM20(7d-50C) sebesar 61,93% dan peningkatan kekuatan mekanik tertinggi pada SM10(7d-50C) sebesar 10,58%.

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Currently there are obstacles in the procurement of special cement that is suitable to be used as an insulating material for CO2 injection wells in Carbon Capture and Storage (CCS). Class-G cement is a base material that can be modified so that it is suitable for use in CO2 injection wells where in the form of a cement and water suspension it is widely used to insulate the annulus spaces in oil and gas wells. Cement suspensions made from Class-G cement experience volume shrinkage during the hardening process. This is one of the disadvantages of Class-G cement when applied without modification. In addition, Class-G cement tends to degrade when exposed to water with high CO2 content. In this study, Class-G cement was modified by adding swelling additives (swelling) CaO and MgO to overcome the volume shrinkage and degradation. In addition, silica flour as a supplementary cementitious material is also used with a composition of 35% by weight of cement (BWOC) before adding the additive. This study aims to examine the impact of the addition of the above additives on changes in corrosion resistance and mechanical strength of cement suspensions in water environments with high CO2 content. Sampling was carried out in the laboratory with various additive compositions (5%, 10%, 15%, and 20% BWOC), cure temperature (26°C and 50°C) and cure time before corrosion test (1 day and 7 days). To simulate water conditions with high CO2 content, the sample was immersed in CO2-saturated water in an autoclave at a pressure of 2.0684 MPa and a temperature of 50°C for 14 days. In addition to the corrosion test, X-Ray Diffraction, Scanning Electron Microscopy/Energy-Disperse X-ray Spectroscopy, Scanning Electron Microscopy, Laser Particle Size Analyzer, Uniaxial Expansive/Shrinkage, Ultrasonic Cement Analyser, Three Point Bending Test, and Macro Photo tests were also conducted. Imaging. The experimental results showed that the addition of CaO additives (composition of 5%, 10%, 15%, and 20% BWOC) and MgO 20% BWOC could prevent volume shrinkage in Class-G cement suspensions. The highest increase in corrosion resistance occurred in the SC15 (1d-26C) sample, which was 70.50%. The highest increase in mechanical strength occurred in the SC5 (1d-50C) sample, which was 43.82%. The highest increase in corrosion resistance due to the addition of MgO additives occurred at SM20(7d-50C) by 61.93% and the highest increase in mechanical strength at SM10(7d-50C) by 10.58%."