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"Dekomposisi katalitik metana adalah salah satu alternatif untuk memproduksi hidrogen dan nanokarbon bermutu tinggi. Penggunaan reaktor unggun tetap untuk reaksi dekomposisi metana masih menjadi pilihan karena desainnya yang ekonomis dengan konversi dan yield yang cukup besar. Penelitian ini dilakukan untuk mengetahui kinerja reaktor unggun tetap skala laboratorium dengan menggunakan dimensi jumlah loading katalis yang lebih besar untuk menghasilkan karbon nanotube. Penelitian ini menggunakan variasi umpan dan laju alir untuk meninjau pengaruhnya terhadap reaksi dekomposisi katalitik metana. Katalis Ni-Cu-Al dipreparasi menggunakan metode kopresipitasi dengan perbandingan 2:1:1. Reaksi dilakukan dengan mengalirkan umpan yang divariasikan (CH4: H2 = 1:0 dan CH4: H2 = 1:1) pada tekanan atmosferik dengan memvariasikan laju alir ( 65 ml/menit dan 100 ml/menit) dan suhu reaksi 700 ̊ C. Produk gas dianalisis menggunakan gas chromatography yang terpasang secara online. Kinerja reaktor ditinjau dari konversi metana, yield karbon, dan kualitas nanokarbon yang dihasilkan. Adapun berdasarkan hasil penelitian diketahui bahwa kinerja reaktor terbaik ditinjau dari konversi dan yield karbon yang dihasilkan terjadi pada reaksi dengan laju alir umpan 100 ml/menit yang memberikan hasil konversi 99,38 % dan yield karbon 1,21 gr C/gr katalis. Hasil analisis menggunakan TEM menunjukkan bahwa morfologi nanokarbon yang paling baik didapat pada umpan CH4: H2 = 1:1.

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Catalytic decomposition of methane is an alternative way to produce high quality carbon nanotubes (CNTs). The use of fixed bed reactors for catalytic decomposition of methane are still an option because its economical design with high conversion and yield. This research was perfomed to study laboratory scale fixed bed reactor performance using larger amount of catalyst loading dimension to produce carbon nanotube. This research uses a variation of feed composition and flow rate to review its influence on catalytic methane decomposition reaction. Ni-Cu-Al catalyst is prepared by coprecipitation method with atomic ratio 2:1:1. The reaction is carried out with the feed flow varied (CH4: H2 = 1:0 dan CH4: H2 = 1:1) at athmospheric pressure by varying the flowrate ( 65 ml/menit dan 100 ml/menit) and the reaction temperature is 700°C. An online gas chromatograph is used to detect the gas products. Reactor performances were observed from methane conversion, carbon yield and quality of nanocarbon that have been produced. Experiment result showed that the highest reactor performance of conversion and the resulting carbon yield in catalytic decomposition of methane with feed flowrate 100 ml/min which give conversion 99.38 % and carbon yield 1.21 gr C/gr catalyst, respectively. Based on TEM analysis indicated that the best nanocarbon morphology can be gained at CH4: H2 ratio of 1:1."

"CuO/TS-1 catalysts have been prepared and tested in the benzene hydroxylation. TS-1 was synthesized by hydrothermal method, while CuO/TS-1 was prepared by impregnation method using Cu(NO)2. 3H2O as precursor. Catalysts were characterized by using X-ray diffraction (XRD), infrared spectroscopy (IR), and N2 adsorption-desorption techniques. The catalytic activity was tested in the hydroxylation reaction of benzene. The products were analyzed using gas chromatography. Catalyst characterization by XRD and IR techniques have showed that the catalyst structure was a MFI type of zeolite. XRD pattern have showed the orthorombic structure and indicated the presence of CuO aggregation. The results of the pyridine adsorption have found that the acidity of TS-1 and CuO/TS-1 were a Lewis acid and it?s increased with an increasing amount of CuO loading. The results of nitrogen adsorption analysis have showed decreasing of surface areas of catalyst with increasing amount of CuO loading. The optimum conditions of benzene hydroxylation was observed by 1%CuO/TS-1 catalyst at 70 °C, reaction time 2 h and acetic acid as the solvent yielded 27.6% of phenol with phenol selectivity was 75.5%"

"Sampel Fe3O4/CuO/TiO2/NGP composites dengan varaisi weight percent NGP 5, 10,15 wt telah sukses disintesis dengan menggunkan metode co-pecipitation. Pengukuran X-ray Diffraction XRD , Energy Dispersive X-ray EDX , Fourier Tansform Infrared FTIR , Vibrating Sample Magnetometer VSM , Thermogravimetric Analysis TGA , nitrogen adsorptionspectroscopy, dan UV-Visible spectroscopy UV-Vis spectroscopy yang digunakan untuk melihat struktur, elemen penyusun, vibrasi molekul, sifat magnetic, stabilitas thermal, luas permukaan, dan nilai band gap dari sampel Fe3O4/CuO/TiO2/NGP composites. Aktivitas catalytic yang diujikan pada sampel yaitu photo-,sono-,sonophoto-catalytic yang dilakukan dengan mengamati degradasi warna methylene blue MB . Hasil dari aktivitas catalytic menunjukan seiring penambahan nanograhene platelets NGP pada sampel meningkatkan kemampuan catalytic composites. Composites dengan 10 wt NGP menunjukan aktivitas catalytic yang paling baik. Kemudian, Ag ditambahkan Fe3O4/CuO/TiO2/NGP composites disintesis dengan menggunakan metode co-precipitation. Fe3O4/CuO/TiO2/NGP/Ag composites dengan variasi weight percent Ag 5, 15, 25 wt dilakukan pengukuran X-ray Diffraction XRD , UV-Visible spectroscopy, dan Thermogravimetric Analysis TGA . Hasil aktivitas catalytic dari Fe3O4/CuO/TiO2/NGP/Ag composites didapatkan bahwa sampel dengan 25wt Ag memiliki kemampuan catalytic yang paling baik dalam mendegradasi methylene blue. Dari hasil aktivitas catalytic tersebut terlihat bahwa Ag dapat meningkatkan kemampuan catalytic sampel.

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Samples of Fe3O4 CuO TiO2 NGP composites were varied weight percent of NGP 5, 10, 15wt were successfully synthesized using co precipitation method. All prepared samples were characterized using X ray Diffraction XRD , Energy Dispersive X ray EDX , Fourier Tansform Infrared FTIR , Vibrating Sample Magnetometer VSM , Thermogravimetric Analysis TGA , nitrogen adsorption spectroscopy, dan UV Visible spectroscopy UV Vis spectroscopy to determine the structure, composisition element, molecules bonding, magnetic properties, thermal stability, surface area, dan band gap of the Fe3O4 CuO TiO2 NGP composites. Catalytic activities were tested to all of samples is photo , sono , sonophoto catalytic to degrade methylene blue MB . The results of catalytic activities showed that the addition of NGP on samples could enhance catalytic ability of samples. Sample with 10wt NGP showed the best catalytic activity than the other variation samples. Fe3O4 CuO TiO2 NGP Ag composites with variation weight percent of Ag 5, 15, 25wt composites were successfully synthesized using co precipitation method and were characterized using X ray Diffraction XRD , UV Visible spectroscopy, dan Thermogravimetric Analysis TGA . The results of cataylytic activities of Fe3O4 CuO TiO2 NGP Ag composites showed that the addition Ag could enhance catalytic ability sample. Sample with 25wt Ag have best catalytic ability than the other samples. "

"ABSTRAKNano Teknologi semakin berkembang sekarang ini. Reaksi dekomposisi katalitik metana merupakan salah satu cara untuk memproduksi nano karbon. Kendala dari proses produksi nano karbon dengan menggunakan reaksi dekomposisi katalitik metana berada pada parameter kinetika yang belum diketahui terutama jika memperhitungkan deaktivasi katalis. Penelitian ini dilakukan untuk mengembangkan model serta menentukan parameter kinetik dari reaksi-reaksi elementer dekomposisi katalitik metana dengan mengikutsertakan reaksi deaktivasi katalis yang akan diselesaikan dengan menggunakan regresi non linear, metode Marquadt. Model menghasilkan nilai pra eksponensial yang berkisar antara 0.00042 hingga 34.3, dengan kisaran nilai energy aktivasi antara 50,274 kJ/mol hingga 104,673kJ/mol

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ABSTRACTNano technology is advancing right now. Catalytic Decomposition of Methane is one of many ways to produce Nano Carbon. The problem with this method is the kinetic parameter especially if we include the deactivation of the catalyst used. This research is done to develop a model to determine the parameter kinetic of catalytic decomposition of methane that includes the deactivation of catalyst and will be solved by using a non linear regression, the Marquadt method. This research gives the pre exponensial number ranging from 0.00042 to 34.3, with activation energy ranging from 50,274 kJ/mol to 104,673kJ/mol"

"ABSTRAKPenelitian ini membahas pengaruh penambahan material nanographene platelets NGP dan nanoparticles Ag pada komposit Fe3O4/CuO/ZnO dengan menggunakan metode sol-gel dilanjutkan dengan metode co-precipitation. Komposit yang terbentuk kemudian dikarakterisasi dengan menggunakan X-ray diffraction XRD , Energy-Dispersive X-ray EDX , Thermal Gravimetric Analysis TGA , Fourier Transform Infrared FT-IR , UV-Visible Diffuse Reflectance UV-Vis , UV-Vis Absorbance spectroscopy, Scanning Electron Microscopy SEM dan Transmission Electron Microscopy TEM . Pengujian karakterisasi menunjukkan bahwa material yang disentasis merupakan gabungan dari nanoparticles Ag, Fe3O4, CuO, ZnO, dan NGP, sesuai dengan yang diinginkan. Pengujian aktivitas catalytic photo-, sono-, dan sonophotocatalytic dilakukan dengan menggunakan methylene blue MB sebagai model polutan pada keadaan cair. Penambahan Ag dan NGP menunjukkan peningkatan aktivitas catalytic dibandingkan dengan pure komposit Fe3O4/CuO/ZnO. Pengujian scavengers didapatkan bahwa hole dan hydroxyl radicals merupakan spesies dominan dalam aktivitas catalytic. Terakhir, sampel yang dibuat menunjukkan kestabilitasan dalam degradasi limbah selama 4 kali percobaan berulang reusability , hal tersebut menunjukkan potensi dari material Ag/Fe3O4/CuO/ZnO/NGP komposit sebagai degradasi limbah.

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ABSTRACTThis research discusses the effect of adding nanographene platelets NGP and Ag nanoparticles onto Fe3O4 CuO ZnO composites by using sol gel method followed by simple co precipitation method. The as prepared composites were characterized using X ray diffraction XRD , Energy Dispersive X ray EDX , Thermal Gravimetric Analysis TGA , Fourier Transform Infrared FT IR , UV Visible Diffuse Reflectance UV Vis , UV Vis Absorbance spectroscopy, Scanning Electron Microscopy SEM dan Transmission Electron Microscopy TEM . Characterization tests show that the as prepared samples are combination of desired Ag, Fe3O4, CuO, ZnO, and NGP nanoparticles. The catalytic activity photo , sono , and sonophotocatalytic was performed using methylene blue MB as the pollutant model in aqueous solution. The addition of Ag nanoparticles and NGP showed an increase in catalytic activity compared to pristine Fe3O4 CuO ZnO composites. The scavengers test showed that hole and hydroxyl radicals are the dominant species in catalytic activity. Finally, the Ag Fe3O4 CuO ZnO NGP composite exhibits good catalytic stability in four times cycling processes."

"Dalam penelitian ini, zeolit KNaX (rasio molar Si/Al = 1,24) disintesis dari kaolin yang berasal dari Pulau Belitung di Indonesia. Zeolit KNaX tersebut digunakan sebagai katalis pada reaksi antara minyak kulit biji mete yang mengandung gugus ?OH fenolik dan karboksil ?COOH dengan metanol menggunakan pelarut DMSO untuk diaplikasikan sebagai biopelumas. Produk katalitik diekstrak menggunakan campuran pelarut etil asetat dan n-heksan dengan perbandingan volume 1:1. Fasa organik dipisahkan dan diuapkan untuk menghilangkan pelarut dan dianalisis menggunakan FTIR & GC-MS.Hasil analisis dengan FT-IR menunjukkan telah terjadi reaksi O-metilasi dan esterifikasi dengan terbentuknya gugus ?OCH3 pada bilangan gelombang 2876,61 cm-1 dan gugus karbonil dari ester pada bilangan gelombang 1732,80 cm-1. Hal ini juga diperkuat dari data GC-MS menunjukkan adanya kenaikan berat molekul dari m/z 300 menjadi m/z 328, mengindikasikan adanya penambahan 2 gugus CH3. Produk reaksi katalitik dikarakterisasi terhadap beberapa parameter pelumas dan diperoleh hasil sebagai berikut: viskositas suhu 40°C = 35,2 cSt dan viskositas suhu 100°C = 4,1 cSt, TAN = 0,88 mg KOH/g sampel, TBN = 2,09 mg KOH/g sampel, densitas = 0,9902, flash point = 120°C dan pour point = -27°C. Selanjutnya dilakukan variasi jumlah pelarut DMSO dan persen berat katalis zeolit KNaX untuk mendapatkan nilai TAN lebih rendah sesuai spesifikasi biopelumas.

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In this research, KNaX zeolite (molar ratio Si/Al = 1,24) was synthesized from kaolin, originating from Belitung Island in Indonesia. KNaX zeolite was used as catalyst in the reaction between cashew nut shell liquid containing phenolic ?OH group and carboxylic ?COOH with methanol using the solvent DMSO for the application as biolubricant. The reaction product was extracted using mixed solvents of ethyl acetate and n-hexane 1:1. The organic phase was separated and evaporated to remove the solvents and was analyzed using FTIR and GC-MS.The FT-IR spectra showed the result of O-methylation and esterification reactions by the formation of ?OCH3 group at 2876,61 cm-1 and carbonyl group from ester at 1732.80 cm-1. These results were also confirmed by the GC-MS analysis result, which showed an increase in molecular weight of m/z 300 to m/z 328, indicating the addition of 2 CH3 groups. The catalysis reaction products were characterized toward several parameters of lubricant which showed the following results: Viscosity 40°C = 35,2 cSt and viscosity temperature of 100°C = 4,1 cSt, TAN = 0,88 mg KOH/g sample, TBN = 2,09 mg KOH/g sample, density = 0,9902, flash point = 120°C and pour point = -27°C. Furthermore, the amount of used DMSO solvent and the percentage of weight catalyst were varied to obtain the reduced TAN values as required for biolubricant."