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"Dalam penelitian ini, nanokomposit CoMoO4/SBA-15 disintesis sebagai katalis bimetal untuk mengubah asam lemak menjadi parafin melalui reaksi deoksigenasi tanpa kehadiran hidrogen atau pelarut. SBA-15 disintesis menggunakan metode sol-gel, dan CoMoO4/SBA-15 (Co:Mo = 5:5 wt%) dibuat melalui metode impregnasi kering (incipient wetness), bersama dengan katalis monometalik Co3O4/SBA-15 ( 10% berat Co), dan MoO3/SBA-15 (10% berat Mo) untuk mengamati pengaruhnya terhadap struktur dan yield serta selektivitas produk hidrokarbon. Difraktogram sinar-X dan mikroskop elektron transmisi menegaskan bahwa proses impregnasi kering partikel logam tidak mengubah struktur heksagonal pendukung katalis, SBA-15. Analisis fisisorpsi isoterm N2 menunjukkan bahwa katalis hasil sintesis memiliki struktur meso dengan kisaran diameter pori 5-6 nm. Uji katalitik dilakukan dalam reaktor semi-batch pada suhu 350 °C selama 2 jam, dan produk dianalisis menggunakan metode Kromatografi Gas – Spektroskopi Massa (GC-MS). Terlihat bahwa komponen utama produk hidrokarbon dari reaksi deoksigenasi adalah pentadekana, salah satu komponen dalam bahan bakar penerbangan. Aktivitas katalitik pada proses deoksigenasi menunjukkan bahwa MoO3/SBA-15 memiliki rendemen tertinggi (94,87%) dan Co3O4/SBA-15 memiliki selektivitas tertinggi untuk C-15 (86,32%). Kondisi reaksi optimal untuk katalis CoMoO4/SBA-15 adalah dengan jumlah katalis 5% wt, dan suhu reaksi 375 °C.......In this study, CoMoO4/SBA-15 nanocomposite was synthesized as a bimetallic catalyst for converting fatty acids into paraffin through a deoxygenation reaction without the presence of hydrogen or solvent. SBA-15 was synthesized using the sol-gel method, and CoMoO4/SBA-15 (Co:Mo = 5:5 wt%) was prepared through dry impregnation (incipient wetness) method, along with monometallic catalysts Co3O4/SBA-15 (10 wt % of Co), and MoO3/SBA-15 (10 wt % of Mo) to observe their effect on the structure and yield and selectivity of the hydrocarbon products. X-ray diffractograms and transmission electron microscopy confirmed that the dry impregnation process of metal particles did not change the hexagonal structure of the catalyst support, SBA-15. Physisorption analysis of the N2 isotherm shows that the as-synthesized catalyst had a meso-structure with a pore diameter range of 5-6 nm. The catalytic test was carried out in semi-batch reactor at 350 °C for 2 hours, and the product was analyzed using Gas chromatography-mass spectroscopy (GC-MS) method. It is shown that the major component of the hydrocarbon product from the deoxygenation reaction is pentadecane, one of components in aviation fuel. The catalytic activity in the deoxygenation process reveals that MoO3/SBA-15 has the highest yield (94.87%) and Co3O4/SBA-15 has the highest selectivity for C-15 (86.32%). The optimal reaction conditions for the CoMoO4/SBA-15 catalyst was 5% by weight of the catalyst, and the reaction temperature was 375 °C."

"Katalis heterogen memiliki berbagai keunggulan diantaranya mudah dipisahkan dengan produk, dapat dipakai ulang dan lebih ramah lingkungan. Sintesis katalis bimetal Ni-Co - yang diammobilisasi dari clay Tapanuli telah dilakukan. Awalnya dilakukan sintesis Na-Bentonit yang bertujuan untuk menyediakan ruang yang cukup untuk ammobilisasi bimetal ke dalam interlayer clay sehingga bimetal dapat terammobilisasi dengan maksimal. Selanjutnya dilakukan ammobilisasi bimetal Ni-Co pada clay Tapanuli sehingga didapatkan katalis bimetal Ni-Co/Na-BP. Katalis bimetal Ni-Co/Na-BP dikarakterisasi menggunakan X-Ray Diffraction, Fourrier Transform Infra Red, Energy Dispersive X-Ray Analysis dan uji katalitik dengan Gas Chromatoghraphy. Hasil Fourrier Transform Infra Red menunjukkan adanya penggantian sejumlah besar kation interlayer yang biasanya ada pada pembentukan hidrat yaitu penurunan intensitas puncak ?OH di bilangan gelombang 1638 cm-1 dan bergeser ke 1628 cm-1 setelah ammobilisasi. Hasil X-Ray Diffraction menunjukkan puncak montmorilonit bergeser dari 2θ = 5,96° ke 8,94° dengan nilai basal spacing sebesar 14,82 Å menjadi 9,86 Å. Hasil ini menunjukkan bahwa logam Ni, dan Co masuk ke interlayer clay melalui mekanisme pertukaran kation. Hasil Energy Dispersive X-Ray Analysis menunjukkan logam Ni dan Co dapat terammobilisasi pada clay dengan perbandingan 1 : 1. Uji katalitik pada reaksi transesterifikasi memperlihatkan bahwa katalis bimetal Ni-Co/Na-BP menghasilkan fatty acid methyl ester terbesar yaitu 2 % serta lebih selektif terhadap produk yang dihasilkan yaitu dapat mengkonversi asam palmitat menjadi metil palmitat lebih banyak sebesar 0,28 %.

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Heterogen catalysts have various advantages, they are easy to separate with their product, can be reusable and environment friendly materials. Synthesis Ni-Co bimetallic catalysts that were ammobilized by Tapanuli clay have been carried out. Firstly the synthesis of Na-Bentonite was conducted to allow enough area for ammobilizing bimetal in the clay interlayer. Secondly bimetal Ni-Co ammobilization in the Tapanuli clay and resulted Ni-Co/Na-BP bimetallic catalysts. The immobilization was characterized by X-Ray Diffraction, Fourrier Transform Infra Red, Energy Dispersive X-Ray Analysis and catalytic test with Gas Chromatoghraphy. Fourrier Transform Infra Red spectra showed subtitution of a high number interlayer cation wich consisted of a hidrated formation. This formation decreased the peak intensity of ?OH and this peak shifted from 1638 cm-1 to 1628 cm-1. X-Ray Diffraction spectra showed the montmorillonit peak of 2θ = 5,96° shifted to 2θ = 8.94° with the alteration of basal spacing from 14.82 Å to 9.86 Å. This result indicated the insertion of Ni and Co in interlayer clay with a cation exchange reaction. Energy Dispersive X-Ray Analysis showed the ammobilized of Ni and Co in clay was in ratio 1: 1. Catalytic test in the transesterification reaction showed that Ni-Co/Na-BP bimetallic catalyst yielded biggest fatty acid methyl ester with the amount of 2 % and also was more selective toward product which yielded higher palmitic acid conversion to methyl palmitic with the amount of 0,28 %."