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Abstrak :
Konversi karbon dioksida menjadi senyawa lain saat ini telah dilakukan secara luas. Namun, konversi CO2 menjadi senyawa lain masih sulit karena CO2 bersifat inert dan stabil pada suhu tinggi. Jadi, dibutuhkan bantuan dari katalis logam bervalensi rendah seperti Ni (0) dan Pd (0). Dalam hal ini, ZSM-5 dari mineral alam disintesis menggunakan zeolit alam Bayat-Klaten dan kaolin Belitung sebagai sumber silika dan alumina. Bahan ini digunakan sebagai katalis untuk reaksi hidrogenasi CO2 (sabatier reaction. Hasil modifikasi Ni (0) pada material yang dihasilkan dikarakterisasi menggunakan FTIR, SEM-EDX, BET dan XRD. Reaksi yang berlangsung dilakukan dengan variasi massa katalis (0,02 gram dan 0,03 gram), suhu katalis (673 K, 773 K, dan 873 K) dan variasi perbandingan gas H2 dan CO2 (1: 3, 1: 4, dan 1:5) untuk melihat kemampuan konversi CO2 menjadi CH4. Proses reaksi hidrogenasi menggunakan flow quartz reactor dan dianalisis dengan Instrumen GC-TCD. Hasil modifikasi Ni/ZSM-5 dan H/ZSM-5 karakterisasi dengan FTIR, SEM-EDX, BET dan XRD. Konversi terbesar yang didapat dari katalis 10% Ni/ZSM-5 sintetik dengan konversi dan yield berturut-turut 60,55% dan 23% pada suhu 773 K.

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Conversion of carbon dioxide into other compounds nowadays have been widely carried out. However, the conversion is still difficult because CO2 is inert and stable at high temperatures. So it requires assistance from low-valence metal catalysts such as Ni (0) and Pd (0). In this work, ZSM-5 was synthesized using Bayat-Klaten natural zeolite and Belitung kaolin as its silica and alumina source. This material was used as support catalyst for CO2 hydrogenation reaction (sabatier reaction). The resulted for Ni (0) materials were characterized using FTIR, SEM-EDX, BET and XRD. The reaction was carried out with variations of catalyst mass (0.02 grams and 0.03 grams) temperature (673 K, 773 K, and 873 K) and mass flow ratio of CO2:H2 (1:3, 1: 4, and 1: 5). This reaction gave product only in the presence of Ni. The higher the Ni content the higher the conversion while the yield methane is unchanged. The highest conversion is shown by synthetic 10% Ni/ZSM-5 with conversion of 60.55% and yield of 23% at 773 K.

Abstrak :
The application of bio-oil for biofuel has been limited due to its low heating value, high acidity and high oxygenate content. pursuant to the urgency of obtaining access to sustainable energy from renewable resources, the studies for bio-oil upgrading have been recently placed in high priority. this study is aimed at identifying the effect of biomass types on bio-oil product characteristics. the conversion of several types of biomass, i.e. rice straw, rubberwood (hevea brasiliensis), and palm empty fruit bunches (efb) to bio-oil by-products was investigated in a catalytic fast pyrolysis (cfp) reactor using a ni/zsm-5 nickel nitrate and zeolite catalyst at 550oc and at atmospheric pressure. the results show that ni/zsm-5 catalyst has actively enhanced the de-oxygenation reaction process and aromatic production. the composition of aromatic compounds in bio-oil from rubberwood, rice straw, and efb are 10.25 wt%, 7.8 wt%, and 5.98 wt%, respectively. in the absence of a catalyst, bio-oil from rice straw contains no aromatics.

Abstrak :
Gas rumah kaca seperti karbon dioksida merupakan gas yang melimpah di alam sehingga diperlukan cara untuk mengkonversi CO2. Namun, CO2 bersifat stabil secara termodinamika dan kinetika sehingga diperlukan bantuan logam bervalensi rendah contohnya Ni(0) atau Pd(0) untuk dapat bereaksi. Pada penelitian ini digunakan ZSM-5 hirarki terimpregnasi logam nikel sebagai katalis reaksi karboksilasi bertekanan antara fenilasetilena dengan karbon dioksida menjadi asam sinamat. ZSM-5 hirarki dianggap mampu menjadi penyangga katalis logam Ni dikarenakan ZSM-5 hirarki memiliki selektivitas dan transport massa yang baik. ZSM-5 Hirarki disintesis menggunakan metode double template yaitu TPAOH sebagai pengarah struktur MFI dan PDD-AM sebagai pengarah mesopori. Impregnasi logam nikel dilakukan menggunakan metode impregnasi basah dengan reduksi oleh aliran gas hidrogen. Karakterisasi material ZSM-5 hirarki dan Ni/ZSM-5 hirarki dilakukan dengan menggunakan XRD, FTIR, XRF, SEM-EDS dan SAA. Analisa XRD menunjukkan ZSM-5 telah berhasil disintesis. Analisa FTIR menunjukkan dekomposisi template melalui kalsinasi telah berhasil. Pencitraan SEM menunjukkan morfologi material dengan bentuk coffin like-shaped yang merupakan ciri khas ZSM-5. Hasil analisa EDS menunjukkan persen loading Ni dalam ZSM-5 sebesar 1,4 %. Sedangkan analisa XRF menunjukkan persen loading Ni dalam ZSM-5 sebesar 3,325 % yang mengindikasikan logam Ni telah masuk ke dalam pori ZSM-5. Analisa BET menunjukkan adanya hysteresis loop yang mengindikasikan adanya pori berukuran meso. Reaksi karboksilasi bertekanan fenilasetilena dilakukan dalam reaktor batch dengan variasi tekanan CO2 (1, 3, 5, 7 bar) dan suhu (85, 100, dan 125 C). Berdasarkan analisa terhadap campuran produk didapat tekanan CO2 optimum sebesar 3 bar dan suhu optimum pada 85 C. ...... Carbon dioxide is one of greenhouse gases which is abundant in nature, therefore efforts are needed to reduce its concentration through CO2 conversion. However, CO2 is thermodynamically and kinetically stable, so it needs low valent metals such as Ni (0) or Pd (0) to help CO2 to react. In this study, the hierarchical ZSM-5 impregnated nickel metal was used as a catalyst for pressurized carboxylation reactions between phenylacetylene and carbon dioxide to cinnamic acid. Hierarchical ZSM-5 is assumed capable for supporting Ni metal catalysts because it has good selectivity and mass transport. Hierarchical ZSM-5 was synthesized using the double template method with TPAOH as structure directing agent for MFI and PDD-AM as mesoporous directing agent. Impregnation of nickel was carried out using a wet impregnation method with reduction by the hydrogen gas flow. Material characterization of hierarchical ZSM-5 and Ni/ZSM-5 was carried out using XRD, FTIR, XRF, SEM-EDS and SAA. XRD analysis shows that ZSM-5 has been successfully synthesized. FTIR analysis showed that the template decomposition through calcination was successful. SEM imaging of the material shows a coffin-like morphology, which is a characteristic of the ZSM-5. The EDS analysis results shows 1.4% Ni in ZSM-5. While the XRF analysis shows 3.325 % Ni in ZSM-5 of which indicates that Ni has entered the ZSM-5 pores. BET analysis shows a hysteresis loop that indicates mesoporous. Pressurized carboxylation reaction of phenylacetylene were carried out in batch reactors with variations of CO2 pressure (1, 3, 5, 7 bar) and temperature (85, 100, and 125 125 C). Based on the analysis of products with HPLC, the optimal CO2 pressure was obtained at 3 bar and the optimal temperature at 85 C.

Abstrak :
Saat ini masih terdapat beberapa kendala dalam penggunaan bio oil sebagai bahan bakar yaitu rendahnya nilai heating value tingginya tingkat keasaman korosif dan tidak stabil disebabkan tingginya kandungan senyawa oksigenat di dalam bio oil Penelitian ini bertujuan untuk mendapatkan bio oil dengan kadar oksigenat lebih rendah dan aromatik lebih tinggi Dalam penelitian ini digunakan metode fast pyrolysis pada temperatur 550oC dengan empat variasi yaitu produksi bio oil tanpa katalis dan produksi bio oil dari 3 jenis biomassa jerami padi kayu karet dan tandan kosong kelapa sawit dengan katalis Ni ZSM 5 Penggunaan katalis terbukti berpengaruh aktif terhadap proses deoksigenasi dan aromatisasi Secara berurutan kandungan senyawa aromatik paling tinggi didapat dari proses pirolisis katalitik biomassa kayu karet 10 25 pirolisis katalitik jerami padi 7 8 pirolisis katalitik TKKS 6 22 dan pada pirolisis non katalitik tidak ditemukan senyawa aromatik Kayu karet merupakan biomassa yang paling banyak mengandung selulosa. ...... There are several obstacles that inhibit the use of bio oil as fuel such as low heating value high levels of acidity corrosive and unstable due to high content of oxygenated compounds in the bio oil This study aims to obtain bio oil with less oxygenated compounds and higher aromatics This study use fast pyrolysis method at 550oC with four variations ie the production of bio oil without catalyst and bio oil production from 3 types of biomass rice straw rubber wood and empty fruit bunches with Ni ZSM 5 catalyst The use of catalyst proved to affect the process of deoxygenation and aromatization Sequentially the high content of aromatic compounds derived from catalytic pyrolysis of rubberwood 10 25 catalytic pyrolysis of rice straw 7 8 catalytic pyrolysis of EFB 6 22 and aromatics were not found in non catalytic pyrolysis Rubber wood is biomass that mostly contain cellulose and hemicellulose as the largest contributor to the content of aromatic hydrocarbons.

Abstrak :
Zeolite Socony Mobil-5 (ZSM-5) merupakan salah satu jenis zeolit dengan struktur MFI yang banyak diaplikasikan sebagai katalis di industri adsorbsi dan proses katalisis, seperti proses hydrotreating fraksi berat minyak bumi. Telah dilakukan literature review mengenai pengaruh waktu kalsinasi terhadap sifat fisik katalis Zeolit ZSM-5 terimpregnasi logam Nikel (Ni/ZSM-5) dan Molibdenum (Mo/ZSM-5). Beberapa sifat fisik yang dipelajari di penelitian ini antara lain kristalinitas, luas permukaan serta volume pori, dan morfologi dari sampel Ni/ZSM-5 dan Mo/ZSM-5 setelah mengalami kalsinasi pada temperatur 550oC selama waktu 2, 3, 4, 5 jam. Karakterisasi XRD, BET, dan SEM telah dilakukan pada beberapa penelitian yang sudah ditinjau. Hasil dari beberapa penelitian ini menunjukkan adanya pengaruh waktu kalsinasi terhadap luas permukaan serta volume pori sampel. Semakin bertambahnya waktu kalsinasi maka luas permukaan dan volume pori sampel Ni/ZSM-5 dan Mo/ZSM-5 akan semakin menurun. Penurunan tertinggi untuk sampel Ni/ZSM-5 terjadi pada waktu kalsinasi 5 jam, yaitu penurunan luas permukaan sebesar 48,10% dan volume pori sebesar 18,64%, serta untuk sampel Mo/ZSM-5 penurunan tertinggi juga terjadi pada waktu kalsinasi 5 jam, yaitu penurunan luas permukaan sebesar 24,93% dan volume pori sebesar 34,69%. Selain itu, waktu kalsinasi juga cukup berpengaruh terhadap morfologi sampel, dimana semakin lama waktu kalsinasi berlangsung, maka dispersi partikel akan lebih baik. Namun, hasil penelitian juga menunjukkan bahwa waktu kalsinasi tidak mempengaruhi kristalinitas dari sampel, yaitu tetap mempertahankan struktur MFI seperti sampel awal ZSM-5 ......Zeolite Socony Mobil-5 (ZSM-5) is a type of zeolite with MFI structure which is widely applied as a catalyst in the industrial of adsorption and catalysis processes, such as the hydrotreating process of heavy petroleum fractions. A literature review has been carried out on the effect of calcination time on the physical properties of the ZSM-5 Zeolite catalyst impregnated by Nickel (Ni/ZSM-5) and Molybdenum (Mo/ZSM-5) catalysts. Some physical properties studied in this study include crystallinity, surface area and pore volume, and morphology of the Ni/ZSM-5 and Mo/ZSM-5 samples after calcining at 550oC for 2, 3, 4, 5 hours. Characterization of XRD, BET, and SEM has been carried out in several studies that have been reviewed. The results of several studies have shown the influence of calcination time on the surface area and pore volume of the sample. The more time of calcination increases the surface area and pore volume of Ni/ZSM-5 and Mo/ZSM-5 samples will decrease, where the highest decrease for Ni/ZSM-5 samples occurs at 5-hour calcination time, ie the surface area decreases by 48,10% and pore volume by 18,64%, and for Mo/ZSM-5 samples the highest decrease also occurred at 5 hour calcination time, ie the surface area decreases by 24.93% and pore volume by 34.69%. The calcination time is also quite influential on the morphology of the sample, where the longer the calcination time lasts, the better particle dispersion will be. However, the results of the study also showed that the calcination time did not affect the crystallinity of the sample, that is still maintained the structure of the MFI like the initial sample ZSM