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"Menurut spesifikasi yang ditetapkan Kementerian ESDM, Biosolar Indonesia (B30) memiliki kandungan sulfur pada takaran yang cukup tinggi (<2000 ppm) jika dibandingkan standar lain seperti EURO VI (<10 ppm) dan EPA (<15 ppm). Kandungan sulfur yang tinggi pada biosolar dapat merugikan secara ekonomi karena merusak komponen mesin diesel dan mencemari lingkungan dengan emisi gas SOx. Oxidative desulfurization (ODS) merupakan metode alternatif untuk menurunkan kadar sulfur pada bahan bakar selain Hydrodesulfurization (HDS). ODS memiliki kondisi operasi pada suhu dan tekanan rendah sehingga secara keekonomian lebih baik. Penelitian ini bertujuan untuk mengetahui performa dari kalium permanganat sebagai oksidator dalam menurunkan kadar sulfur pada biosolar Indonesia. Vairabel yang dipakai adalah jumlah kalium permanganat, katalis yang digunakan, dan waktu oksidasi. Untuk mengetahui kadar sulfur sebelum dan sesudah proses ODS, digunakan metode FTIR. ODS Biosolar Indonesia menggunakan kalium permanganat katalis asam asetat dapat menghasilkan derajat desulfurisasi hingga 28,12% dengan waktu oksidasi selama 30 menit.

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According to the specifications set by the Ministry of Energy and Mineral Resources, Indonesian Biosolar (B30) has a high sulfur content (<2000 ppm) when compared to other standards such as EURO VI (<10 ppm) and EPA (<15 ppm). High sulfur content in biodiesel can be economically detrimental because it damages diesel engine components and pollutes the environment with SOx gas emissions. Oxidative desulfurization (ODS) is an alternative method to reduce sulfur content in fuels other than Hydrodesulfurization (HDS). ODS has operating conditions at low temperature and pressure so that it is economically better. This study aims to determine the performance of potassium permanganate as an oxidizing agent in reducing sulfur content in Indonesian biodiesel. The variables used were the amount of potassium permanganate, the catalyst used, and the oxidation time. To determine the sulfur content before and after the ODS process, the FTIR method was used. ODS Biosolar Indonesia using potassium permanganate acetic acid catalyst can produce a degree of desulfurization up to 28.12% with an oxidation time of 30 minutes."

"Penelitian ini dilakukan untuk untuk mengetahui pengaruh proses desulfurisasi oksidatif (ODS) dengan high-speed mixer dan ekstraksi untuk mengurangi kadar sulfur pada bahan bakar. ODS terdiri dari dua proses yaitu oksidasi dan separasi. Pada proses oksidasi, hidrogen peroksida digunakan sebagai oksidator dan dikombinasikan dengan asam format sebagai katalis. Oksidasi dilakukan menggunakan high-speed mixer sebagai reaktor tempat oksidator dan katalis bereaksi dengan sampel Pertamina Dex yang diuji. Tiga jenis pelarut, metanol, etanol, dan isopropanol diuji untuk menghasilkan persen desulfurisasi tertinggi. Selain itu, penelitian ini juga memvariasikan waktu pencampuran sebesar 10, 20, dan 30 menit, waktu oksidasi sebesar 30, 45, dan 60 detik, dan suhu 30, 35, dan 40oC. Metode FTIR digunakan untuk mengetahui kadar sulfur sebelum dan sesudah proses ODS dilakukan. Hasil penelitian menunjukkan bahwa proses desulfurisasi oksidatif menggunakan reaktor high-speed mixer menghasilkan persentase ODS tertinggi sebesar 19,41% dengan menggunakan pelarut metanol, waktu pencampuran dengan pelarut selama 20 menit, waktu oksidasi selama 30 detik, dan suhu sebesar 40 oC.

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This research was conducted to determine the effect of the oxidative desulfurization (ODS) process with a high-speed mixer and extraction to reduce sulfur content in fuel. ODS consists of two processes namely oxidation and separation. In the oxidation process, hydrogen peroxide is used as an oxidizing agent and combined with formic acid as a catalyst. Oxidation was carried out using a high-speed mixer as the reactor where the oxidizer and catalyst reacted with the Pertamina Dex sample being tested. Three types of solvents, methanol, ethanol, and isopropanol were tested to produce the highest desulfurization percent. In addition, this study also varied the mixing time by 10, 20 and 30 minutes, the oxidation time by 30, 45 and 60 seconds, and the temperature at 30, 35 and 40oC. The FTIR method is used to determine sulfur content before and after the ODS process is carried out. The results showed that the oxidative desulfurization process using a high-speed mixer reactor resulted in the highest ODS percentage of 19.41% using methanol solvent, mixing time with solvent for 20 minutes, oxidation time for 30 seconds, and temperature of 40 oC.

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"Tingginya kadar sulfur dalam bahan bakar diesel dapat menyebabkan kerusakan mesin kendaraan dan berdampak buruk pada lingkungan. Salah satu metode yang efisien dalam proses penghilangan sulfur adalah oxidative desulfurization (ODS). Penelitian ini mempelajari pengaruh promotor Ce sebagai oxygen storage pada katalis Ni-Mo/Al2O3 dalam reaksi ODS untuk menurunkan senyawa sulfur dibenzothiophene dalam diesel dengan menggunakan hidrogen peroksida dan asam format sebagai oksidator. Pada penelitian terdahulu diperoleh konversi DBT dalam pelarut n-heptana sebesar 99% dengan menggunakan promotor Fe pada katalis Ni-Mo/Al2O3. Pada studi ini, katalis Ce promoted Ni-Mo/Al2O3 berhasil disintesis dengan menggunakan metode wet impregnation. Katalis dikarakterisasi dengan SEM, XRF dan BET Surface Area Analysis. Kapasitas penyimpanan oksigen katalis diperoleh melalui studi adsorpsi isotermal oksigen pada suhu ruang dengan tekanan oksigen yang divariasikan. Diamati pengaruh kondisi operasi terhadap konversi DBT yang meliputi pengaruh penambahan asam kuat, suhu reaksi, waktu kontak, Ce loading, volume oksidator dan dosis katalis. Kadar sulfur pada produk dianalisis dengan UV-Vis Spektrofotometer pada panjang gelombang 200 – 400 nm. Hasilnya diperoleh bahwa Cerium mampu meningkatkan kapasitas adsorpsi oksigen sebesar 39% menjadi 101,1 µmol/g katalis. Cerium juga mampu mengkonversi DBT sebesar 90% yang mengalami peningkatan 216% dibandingkan katalis tanpa Cerium. Studi kinetika reaksi ODS diinvestigasi dengan pseudo-first order kinetic model dan diperoleh nilai energi aktivasi sebesar 41,304 KJ/mol.

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High content of sulfur in diesel fuel can cause damage to diesel engines and have negative impact on the environment. One of the efficient methods in the sulfur removal process is oxidative desulfurization (ODS). This research investigates the effect of Ce promotor as an oxygen storage over Ni-Mo/Al2O3 catalyst in ODS reaction of dibenzothiophene (DBT) in diesel fuel using hydrogen peroxide and formic acid as oxidants. In the previous research, the yield of DBT conversion in n-heptane solvent using Fe as promotor over Ni-Mo/Al2O3 catalyst was 99%. In this study, Ce promoted Ni-Mo/Al2O3 catalyst was successfully synthesized by using wet impregnation method. The catalyst then characterized using SEM, XRF and BET Surface Area Analysis. The oxygen storage capacity of the catalyst was gained from oxygen isotherm study at room temperature with vary oxygen pressures. The operation over the conversion of DBT was observed including the effect of strong acid addition, reaction temperature, contact time, Ce loading, oxidants volume and catalyst dose. The sulfur content of product was analyzed by using UV-Vis Spectrophotometer at wavelength 200 – 400 nm. The result showed that Cerium was able to increase 39% of oxygen adsorption capacity became 101.1 µmol/g catalyst. Cerium also converted 90.0% of DBT, increasing 216% compare to the catalyst without Cerium. The kinetic study of ODS reaction was investigated by using pseudo-first order kinetic model and the activation energy value of 41.304 KJ/mol was gained."

"Cracks was found in type 347 stainless steel internal attachment welds of a reactor for a high temperature, and high pressure hydrogen service. One of the possible causes of cracking is low cycle fatigue cracking induced by repetition of thermal stress to embrittled weld metal. Type 347 weld metal loses its ductility by presence of sigma phase and hydrogen."

"A small batch reactor complete with a stirrer was used to conduct biological coal desulphurisation using a mixed culture, dominated by Thiobacillus ferroxidans. Using the Zwietering formula, the minimum speed of stirrer rotation for the reactor to maintain the coal and medium in a state of complete suspension was calculated. The amount of pytric sulphur removal was affected by a change in the speed of the stirrer rotation. The result showed that a change in stirrer rotation from 125 rpm to 175 rpm caused an increase of pytric sulphur removal whereas if the coal slurry concentration increased to 25% and 35% w/v, there was a decrease."