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"Penelitian ini bertujuan memproduksi hidrogen (H2) dan carbon nanotube (CNT) secara simultan melalui reaksi dekomposisi katalitik metana dengan katalis Ni-Cu-AL. Secara garis besar, penelitian dibagi menjadi dua tujuan besar yaitu studi kinetika intrinsik dan pemodelan reaktor. Studi kinetika didekati dengan tiga cara. Model reaktor yang dibuat adalah reaktor pelat sejajar. Studi kinetika dengan internal reaktor pelat sejajar menghasilkan kinetika non-intrinsik. Pelapisan katalis pada pelat sebanyak 4 kali tidak mempunyai pengaruh yang signifikan pada loading katalis.Hasil eksperimen diverifikasi menggunakan kriteria-kriteria limitasi tahanan massa dan panas (eksternal dan internal). Hasil verifikasi menunjukkan bahwa kinetika pelat sejajar tidak mampu mengatasi limitasi tahanan internal. Studi kinetika diperbaiki dengan internal reaktor berupa katalis serbuk. Studi kinetika serbuk menghasilkan kinetika intrinsik. Tetapi hasil ini tidak akurat karena deposisi karbon dihitung melalui neraca karbon terhadap waktu (pendekatan dinamik) padahal rata-rata 43,45% karbon hilang di akhir reaksi. Studi kinetika dilanjutkan menggunakan reaktor yang dilengkapi dengan microbalance. Kinetika model ini dapat mengukur pertambahan karbon sebagai fungsi waktu dan suhu pada tekanan atmosfer.Hasil penelitian sebelum deaktivasi menunjukkan bahwa tahap pembatas laju reaksi adalah tahap adsorpsi. Energi aktivasi yang diperoleh sebesar 67,76 kJ/mol dan faktor pre-eksponensial 5,15 x 1018. Model persamaan kinetika deaktivasi katalis mempunyai persamaan laju deaktivasi orde satu. Reaktor katalis terstruktur pelat sejajar dimodelkan tiga dimensi (3D) kondisi stedi. Model 3 dimensi diselesaikan dengan program aplikasi computional fluid dynamics (CFD) yaitu COMSOL. Konversi metana dan yield hydrogen digunakan sebagai data validasi antara model dan data hasil eksperimen. Hasil simulasi mempunyai persentase kesalahan konversi total metana dan yield H2 berturut-turut 0,77% dan 2,38%. Validasi menunjukkan bahwa hasil model reaktor sesuai dengan data hasil percobaan laboratorium.

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This study aims to produce hydrogen (H2) and carbon nanotube (CNT) simultaneously through methane decomposition reaction over a Ni-Cu-Al catalyst. The research is divided into two major objectives namely intrinsic kinetics study and reactor modeling. Kinetics studies were approached in three ways. Reactor model is made parallel flat plate reactor.The result of kinetics study using internal reactor parallel-plate was nonintrinsic kinetics. Coating 4 times on the parallel plate had no significant effect on catalyst loading. The experimental results are verified using the criteria for limitation of mass and heat resistance (external and internal). Verification results show that kinetics of parallel-plate are not able to overcome the internal resistance limitation. Kinetics studies corrected with the reactor's internal form of the catalyst powder.This experiment result is not accurate because of carbon deposition is calculated by carbon balance versus time (dynamic approach) whereas the average 43.45% of carbon lost by the end of the reaction. The last study using the reactor which is equipped with a microbalance. This model can measure carbon growth as a function of time and temperature at atmospheric pressure. The results before deactivation suggests that the limiting step is the adsorption. The activation energy of 67.76 kJ/mol and preexponential factor of 5.15 x 1018. Deactivation kinetics model have first order. Parallel-plate structured catalyst reactor is modeled three-dimensional (3D) with steady condition. 3-dimensional model solved by the application program computational fluid dynamics (CFD) namely COMSOL. Methane conversion and hydrogen yield used as validation between model and experimental data. The simulation results have an error percentage of the total methane conversion and H2 yield respectively 0.77% and 2.38%. Validation showed that the model in line with experimental data."

"[ABSTRAKIndustri bahan bakar bio berkembang dengan cepat sebagai konsekuensi dari naiknya harga minya dan meningkatnya kepedulian terhadapa perubahan iklim global. Produksi biodiesel dari transesterifikasi minyak nabati saat ini merupakan rute yang utama untuk menghasilkan bahan bakar nabati (BBN) untuk mesin diesel. Namun, biodiesel memiliki viskositas tinggi, titik kabaut dan tuang yang tinggi, emisi nitrogen oksida (NOx) yang lebih tinggi, densitas energi rendah dan keausan injektor/mesin tinggi. Beberapa rute telah dicoba untuk mengurangi viskositas, seperti blending minyak nabati dengan bahan bakar diesel, mikroemulsi dengan alkohol, pirolisis dan hidrodeoksigenasi (HDO). Solar terbarukan melalui HDO dapat dihasilkan dari beragam bahan baku minyak nabati seperti minyak sawit dan minyak jarak pagar tanpa mengorbankan kualitas bahan bakar. Reaksi pembentukan solar terbarukan melalui HDO minyak nabati melibatkan katalis untuk menurunkan energi aktivasi reaksi dan meningkatkan selektifitasnya. Jenis katalis yang digunakan didalam studi ini adalah katalis berbasi Pd dan berbasis NiMo yang disanggakan pada ZAL atau C. Metode microwave polyol process (MP) cocok untuk preparasi katalis berbasis Pd sedangkan metode rapid cooling (RC) cocok untuk preparasi katalis berbasis NiMo. HDO asam oleat sebagai senyawa model, minyak sawit dan minyak jarak pagar dilakukan pada suhu 375°C dan 400°C dengan tekanan H2 15 bar didalam reaktor autoclave 250 ml semibatch berpengaduk. Didalam HDO, katalis Pd/ZAL-1 selektif terhadap jalur dekarboksilasi sedangakan katalis NiMo/ZAL selektif terhadap jalur dekarboksilasi dan dekarbonilasi katalitik. Soalr terbarukan yang dihasilkan dari HDO memiliki densitas dan viskositas yang sesuai sesuai dan indeks setana yang lebih tinggi disertai dengan kesetaraan dalam kualitasnya dengan solar komersial turunan minyak bumi namun sedikit lebih rendah daripada solar terbarukan komersial (NExBTL®).;

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ABSTRACTThe biofuels industry is growing rapidly as a result of high petroleum prices and increasing concerns about global climate change. Biodiesel production from trans-esterification of vegetable oils is currently the primary route for production of diesel engine biofuels from vegetable oils. However, biodiesel still has higher viscosity, higher cloud point and pour point, higher nitrogen oxides (NOx) emissions, lower energy density, and higher injector/engine wear. Several routes have been tried for reducing this viscosity, such as diluted vegetable oil with diesel fuel, microemulsification with alcohols, pyrolysis and hydrodeoxygenation (HDO). Renewable diesel through HDO can be produced from many kind of vegetable oil feeed stock such as palm oil (edible oil) and jatropha curcas (non-edible oil)without compromising fuel quality. Forming reaction of renewable diesel through HDO vegetable oil involves catalyst to decrease the activation energy of the reaction and increase its selectivity. The type of catalyst used in this study is Pd and NiMo supported on ZAL or C. Microwave polyol method (MP) is suitable for preparation of Pd-based catalyst while rapid cooling method (RC) is suitable for preparation of NiMo-based catalyst. The HDO of oleic acid as model compound, palm oil and jatropha curcas oil were carried out at temperature of 375°C and 400°C with H2 pressure of 15 bar in a 250 mL semibatch stirred autoclave reactor. In HDO, Pd/ZAL-1 catalyst was selective to decarboxylation route while NiMo/ZAL was selective to decarboxylation and catalytic decarbonilation. Renewable diesel synthesized through HDO have suitable density and viscosity and quite high cetane index with similar in their quality with comercial diesel derived from crude oil but slightly lower than comercial renewable diesel (NExBTL®).;The biofuels industry is growing rapidly as a result of high petroleum prices and increasing concerns about global climate change. Biodiesel production from trans-esterification of vegetable oils is currently the primary route for production of diesel engine biofuels from vegetable oils. However, biodiesel still has higher viscosity, higher cloud point and pour point, higher nitrogen oxides (NOx) emissions, lower energy density, and higher injector/engine wear. Several routes have been tried for reducing this viscosity, such as diluted vegetable oil with diesel fuel, microemulsification with alcohols, pyrolysis and hydrodeoxygenation (HDO). Renewable diesel through HDO can be produced from many kind of vegetable oil feeed stock such as palm oil (edible oil) and jatropha curcas (non-edible oil)without compromising fuel quality. Forming reaction of renewable diesel through HDO vegetable oil involves catalyst to decrease the activation energy of the reaction and increase its selectivity. The type of catalyst used in this study is Pd and NiMo supported on ZAL or C. Microwave polyol method (MP) is suitable for preparation of Pd-based catalyst while rapid cooling method (RC) is suitable for preparation of NiMo-based catalyst. The HDO of oleic acid as model compound, palm oil and jatropha curcas oil were carried out at temperature of 375°C and 400°C with H2 pressure of 15 bar in a 250 mL semibatch stirred autoclave reactor. In HDO, Pd/ZAL-1 catalyst was selective to decarboxylation route while NiMo/ZAL was selective to decarboxylation and catalytic decarbonilation. Renewable diesel synthesized through HDO have suitable density and viscosity and quite high cetane index with similar in their quality with comercial diesel derived from crude oil but slightly lower than comercial renewable diesel (NExBTL®)., The biofuels industry is growing rapidly as a result of high petroleum prices and increasing concerns about global climate change. Biodiesel production from trans-esterification of vegetable oils is currently the primary route for production of diesel engine biofuels from vegetable oils. However, biodiesel still has higher viscosity, higher cloud point and pour point, higher nitrogen oxides (NOx) emissions, lower energy density, and higher injector/engine wear. Several routes have been tried for reducing this viscosity, such as diluted vegetable oil with diesel fuel, microemulsification with alcohols, pyrolysis and hydrodeoxygenation (HDO). Renewable diesel through HDO can be produced from many kind of vegetable oil feeed stock such as palm oil (edible oil) and jatropha curcas (non-edible oil)without compromising fuel quality. Forming reaction of renewable diesel through HDO vegetable oil involves catalyst to decrease the activation energy of the reaction and increase its selectivity. The type of catalyst used in this study is Pd and NiMo supported on ZAL or C. Microwave polyol method (MP) is suitable for preparation of Pd-based catalyst while rapid cooling method (RC) is suitable for preparation of NiMo-based catalyst. The HDO of oleic acid as model compound, palm oil and jatropha curcas oil were carried out at temperature of 375°C and 400°C with H2 pressure of 15 bar in a 250 mL semibatch stirred autoclave reactor. In HDO, Pd/ZAL-1 catalyst was selective to decarboxylation route while NiMo/ZAL was selective to decarboxylation and catalytic decarbonilation. Renewable diesel synthesized through HDO have suitable density and viscosity and quite high cetane index with similar in their quality with comercial diesel derived from crude oil but slightly lower than comercial renewable diesel (NExBTL®).]"