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Ahmad Ali Ibrahim
"Karbon mesopori berhasil disintesis menggunakan metode template lunak dengan Pluronic F-127 sebagai agen struktural; phloroglucinol dan formaldehida sebagai prekursor karbon. Karbon mesopori yang berhasil disintesis kemudian dimodifikasi menggunakan etilendiamin, yang kemudian diimpregnasi dengan nanopartikel Ni. Hasil modifikasi dan impregnasi tersebut dikarakterisasi dengan FTIR, SEM-EDX, BET, dan XRD. Pengujian kapasitas adsorpsi MC, Ni-MC, MC-EDA, dan Ni-EDA MC dilakukan dengan mengalirkan gas CO2 selama 5, 10, dan 15 menit untuk melihat kemampuan adsorpsi CO2. Bahan Ni-MC dan Ni-EDA MC kemudian digunakan sebagai katalis dalam reaksi Hidrogenasi, yaitu reaksi antara molekul hidrogen (H2) dengan unsur atau senyawa lain yang melibatkan suatu katalis. Reaksi hanya dapat berlangsung jika terdapat Ni(0) sebagai pusat aktif pada karbon mesopori. Berbagai parameter katalis yang digunakan meliputi; variasi suhu, variasi jumlah katalis, dan variasi waktu. Proses reaksi hidrogenasi menggunakan reaktor aliran dan dianalisis menggunakan instrumen GC-TCD. % rendemen yang diperoleh dari katalis Ni-MC dan Ni-EDA MC berturut-turut adalah 3,54% dan 3,86% pada suhu 873 K. Pada variasi jumlah katalis, % rendemen diperoleh bahan Ni-MC dengan massa katalis 0,02 g sebesar 4,37% sedangkan Ni-EDA MC diperoleh % rendemen sebesar 4,45% dengan massa katalis 0,03 gr. Untuk melihat hambatan katalis dilakukan dengan variasi waktu. Bahan Ni-MC optimum diuji selama 30 menit dengan rendemen 13,32%, sedangkan MC Ni-EDA optimum pada rentang waktu 40 menit dengan rendemen 13,26%.

Mesoporous carbon was successfully synthesized using the soft template method with Pluronic F-127 as a structural agent; phloroglucinol and formaldehyde as carbon precursors. The successfully synthesized mesoporous carbon was then modified using ethylenediamine, which was then impregnated with Ni nanoparticles. The results of these modifications and impregnations were characterized by FTIR, SEM-EDX, BET, and XRD. The adsorption capacity of MC, Ni-MC, MC-EDA, and Ni-EDA MC was tested by flowing CO2 gas for 5, 10, and 15 minutes to see the CO2 adsorption ability. Ni-MC and Ni-EDA MC materials are then used as catalysts in Hydrogenation reactions, namely reactions between hydrogen molecules (H2) with other elements or compounds involving a catalyst. The reaction can only take place if there is Ni(0) as the active center on the mesoporous carbon. Various parameters of the catalyst used include; variations in temperature, variations in the amount of catalyst, and variations in time. The hydrogenation reaction process uses a flow reactor and is analyzed using the GC-TCD instrument. The % yields obtained from Ni-MC and Ni-EDA MC catalysts were 3.54% and 3.86% at a temperature of 873 K, respectively. In the variation of the amount of catalyst, the % yield was obtained for Ni-MC material with a catalyst mass of 0.02 g of 4.37% while Ni-EDA MC obtained % yield of 4.45% with a catalyst mass of 0.03 g. To see the catalyst resistance is done with time variations. The optimum Ni-MC material was tested for 30 minutes with a yield of 13.32%, while the optimum Ni-EDA MC was tested for a period of 40 minutes with a yield of 13.26%."
Depok: Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Indonesia, 2019
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UI - Skripsi Membership  Universitas Indonesia Library
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Iqlima Amelia
"Sintesis karbon mesopori secara soft template dan hard template dari berbagai prekursor karbon; phloroglucinol, glukosa, dan hidrolisat tandan kosong kelapa sawit (TKKS) telah dilakukan. Pluronic F127 dan silica gel digunakan sebagai cetakan pada sintesis karbon mesopori soft template dan hard template, secara berturut-turut. Material karbon mesopori kemudian diimpregnasi dengan logam Ni dan direduksi menggunakan gas H2 sehingga membentuk Ni/mesoporous carbon (Ni/MC). Karakterisasi material dengan FTIR menunjukkan bahwa gugus organik pada soft templated mesoporous carbon (ST MC) menghilang setelah proses karbonisasi dan pada hard templated mesoporous carbon (HT MC) setelah proses desilikasi, mengindikasikan bahwa proses tersebut efektif dalam penghilangan template yang digunakan. Berdasarkan analisis SEM, material karbon memiliki morfologi seperti serpihan dengan tambahan sebaran butiran halus setelah impregnasi. Berdasarkan hasil analisis XRD untuk ST MC dan HT MC, terdapat difraksi khas karbon grafit pada 2θ 25⁰ dan 44⁰. Kemudian terdapat tambahan difraksi setelah impregnasi pada 2θ 45⁰ dan 52⁰ yang bersesuaian dengan Ni(0), mengindikasikan bahwa impregnasi berhasil dilakukan. Analisa luas permukaan menunjukkan bahwa material karbon memiliki luas permukaan dan distribusi pori yang bervariasi. Material selanjutnya digunakan sebagai katalis dalam reaksi karboksilasi fenilasetilena dengan karbon dioksida. Analsis HPLC menunjukkan hasil terbaik pada suhu reaksi 85⁰C dan waktu reaksi 8 jam dengan menggunakan katalis HT Ni/MC phloroglucinol dan garam MgCl2. Yield pembentukan produk asam fenil propiolat pada kondisi tersebut adalah 2,2 %.

Synthesis of soft templated and hard templated mesoporous carbon from various carbon precursors; phloroglucinol, glucose, and empty palm oil shell hidrolisate, has been conducted successfully. Pluronic F127 and silica gel were used as template in the sythesis of soft and hard templated mesoporous carbon, respectively. The materials were then impregnated with Ni and reduced under H2 flow to form Ni/Mesoporous Carbon (Ni/MC). Characterization with FTIR shows that the organic groups in Soft Templated Mesoporous Carbon (ST MC) disappear after the carbonization process and in Hard Templated Mesoporous Carbon (HT MC) after the desilication process, indicating that the process is effective in template removal. Based on the SEM analysis, carbon materials have flakes-like morphology with the addition of fine grain spreads after impregnation. Based on the results of XRD analysis for ST MC and HT MC, there are a typical graphite carbon diffractions on 2θ of 25 and 44 ⁰. There are also additional diffraction peaks at 2θ of 45 and 52⁰ after impregnation which correspond with Ni(0), indicating that the Ni impregnation was successfully performed. The analysis of the surface area indicates that carbon materials have various surface area and pore distribution. The materials are subsequently used as a catalyst in the carboxylation reaction of phenylacetylene with carbon dioxide. HPLC analysis shows the best resultis obtained at reaction temperature of 85 ⁰ _C and time of 8 hour using MgCl2 salt and HT Ni/MC phloroglucinol catalyst. Yield of phenyl propiolic acid formation as product of carboxylation obtained on optimum condition is 2,2%.
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Depok: Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Indonesia, 2020
T54597
UI - Tesis Membership  Universitas Indonesia Library
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Patrik Chandra
"Salah satu isu terbesar di bidang lingkungan adalah perubahan iklim yang diakibatkan oleh emisi gas CO2 yang terus mengalami peningkatan setiap tahunnya. Upaya yang dapat dilakukan untuk mengurangi emisi gas CO2 adalah dengan menangkapnya lalu mengubahnya menjadi bahan kimia yang lebih bernilai melalui reaksi kimiawi, salah satunya adalah reaksi hidrogenasi. Namun, dikarenakan sifat CO2 yang stabil, dibutuhkan katalis untuk menjalankan reaksi hidrogenasi CO2. Pada penelitian ini, material NiAg/NH2pr-Ph- PMO disintesis sebagai katalis sebagai kayauntuk digunakan sebagai katalis heterogen pada konversi CO2 menjadi bahan kimia yang bernilai tambah melalui reaksi hidrogenasi. NiAg/NH2pr-Ph-PMO yang disintesis dikarakterisasi menggunakan FTIR, SEM-EDX Mapping, TEM, BET-BJH, SAXS, dan XRD untuk melihat sifat fisika dan kimia serta membuktikan keberhasilan sintesisnya. Reaksi hidrogenasi CO2 dilakukan dalam reaktor unggun tetap dengan temperatur, rasio bimetal, dan rasio campuran gas yang bervariasi. Analisis XRD menunjukkan keberhasilan impregnasi NiAg bimetalik pada NH2pr-Ph-PMO. Hasil SEM-EDX Mapping menunjukkan persebaran logam nikel dan perak yang merata pada permukaan NH2pr-Ph-PMO. Karakterisasi TEM menunjukkan NiAg/NH2pr-Ph-PMO memiliki saluran pori yang membuktikan keberhasilan sintesis material mesopori. Berdasarkan hasil yang diperoleh, diketahui bahwa NiAg/NH2pr-Ph-PMO memiliki aktivitas katalitik yang lebih baik dibandingkan Ni/NH2pr-Ph- PMO, Ag/NH2pr-Ph-PMO, maupun katalis NiAg tanpa pendukung. Pada temperatur 225℃ dan rasio laju alir gas CO2:H2 sebesar 1:7, diperoleh persen konversi CO2 maksimum yaitu sebesar 39,12% dengan yield dan selektifitas terhadap formaldehid berturut-turut sebesar 28,1 mmol/g dan 70,59%. Uji reusabilitas menunjukkan bahwa setelah 4 siklus reaksi, katalis NiAg/NH2pr-Ph-PMO masih memiliki persen konversi CO2 di atas 35%. Nilai TOF yang diperoleh pada kondisi optimum adalah 62,98 h-1.
.....Climate change that is caused by the always increasing carbon dioxide emission in atmosphere is one of the biggest issue in the environmental study. One way to solve that problem is through CO2 capture and utilization. CO2 can be converted into more valuable chemical product through many chemical reactions, in which hydrogenation is one of them. However, CO2 is a stable and inert molecule thus, a catalyst is needed to achieve a high percentage of its conversion. In this work, NiAg/NH2pr-Ph-PMO is synthesized to be applied as heterogeneous catalyst for CO2 hydrogenation. The catalyst is characterized using SEM- EDX Mapping, TEM, BET-BJH, XRD, SAXS and FTIR to evaluate its physical and chemical properties. BET-BJH analysis shows type IV isotherm for the synthesized NH2pr-Ph-PMO, meaning it can be classified as a mesoporous material. From the SEM-EDX Mapping result, both nickel and silver are found to be distributed evenly in the NH2pr-Ph-PMO surface. TEM images show that NiAg/NH2pr-Ph-PMO has mesoporous channel. Furthermore, the average particle size of NiAg/NH2pr-Ph-PMO is analyzed through small angle X-ray scattering and is found to be 44 nm. Catalytic CO2 hydrogenation is conducted in a fixed-bed reactor with variations of temperature and flow rate ratio between CO2 and H2 It is found that NiAg/NH2pr- Ph-PMO has a higher CO2 conversion percentage compared to Ni/NH2pr-Ph-PMO, Ag/NH2pr- Ph-PMO, and NiA without support. On the optimum condition, which is 225℃ and 1:7 flow rate ratio of CO2:H2 flow, the percentage of CO2 conversion using NiAg/NH2pr-Ph-PMO is 39.12% with formaldehyde yield and selectivity of 28.1 mmol/g and 70.59% respectively. The reusability test shows that after 4 cycles, NiAg/NH2pr-Ph-PMO is still able to convert more than 35% of CO2 which makes it a reusable catalyst for CO2 hydrogenation. The TOF value obtained at optimum condition is 62.98 h-1."
Depok: Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Indonesia, 2022
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UI - Skripsi Membership  Universitas Indonesia Library
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Novelia Sinta Rahmawati
"Pembakaran batubara sebagai sumber energi fosil utama dunia menghasilkan produk samping berupa limbah fly ash. Produk samping ini termasuk ke dalam limbah berbahaya dan bersifat toksik. Jumlahnya yang melimpah dan terus bertambah dapat menimbulkan polusi bagi lingkungan sekitar. Dengan demikian, perlu dilakukan upaya pemanfaatan fly ash, salah satu caranya adalah sintesis silika mesopori sebagai media nutrient tanaman. Adanya kandungan silika (SiO2) sebesar 35 – 60 % dalam fly ash, sangat berpotensi dan sesuai untuk dimanfaatkan sebagai sumber silika dalam mensintesis silika mesopori. Pada penelitian ini, telah dilakukan sintesis silika mesopori yang berasal dari fly ash beserta pengaplikasiannya sebagai pupuk urea slow-release fertilizer (SRF). Silika mesopori yang dihasilkan kemudian dikarakterisasi dengan XRD, XRF, FTIR, SAA, dan UV-Vis. Hasil analisis XRD dan XRF pada pretreatment fly ash menunjukkan keberhasilan dalam proses penghilangan pengotor dengan indeks keberhasilan 82% dalam meningkatkan komposisi silika. Pada penelitian ini variasi paling optimum untuk menghasilkan material mesopori didapatkan oleh 2% CTAB yang dibuktikan dengan hasil analisis XRF dengan komposisi silikanya sebesar 97% dan dengan analisis SAA dengan SBET 1016 m2/g serta Sext 912 m2/g. Silika mesopori dengan 2% CTAB memiliki kemampuan swelling paling besar dengan ratio swelling 2.79 dibandingkan dengan variasi 1% CTAB dan 3% CTAB yang masing masing memiliki ratio swelling sebesar 2.27 dan 1.12.

Coal combustion, the world's main fossil energy source, produces a by-product known as fly ash waste, which is classified as hazardous waste and toxic in nature. The abundance and proliferation of fly ash have polluted the environment. Therefore, it is necessary to optimize the utilization of fly ash in a variety of methods, one of which is use as a raw material for the synthesis of silica mesoporous as a plant nutrient medium. Around 35-60% of silica (SiO2) content, fly ash has emerged as a highly promising and suitabel source of silica for the synthesized of mesoporous silica. In this study, mesoporous silicas derived from fly ash were synthesized using sol-gel technique and applied as urea slow-release fertilizer. Silica mesoporous were then characterized using XRD, XRF, FTIR, SAA, and UV-Vis. The findings of XRD and XRF analysis on fly ash pretreatment indicated that 82% of impurities were successfully removed, therefore the silica composition was increased. In this research to obtain mesoporous material 2% CTAB achieved the best results, as evidenced by the XRF analysis with a silica composition of 97% and surface area of SBET 1016 m2/g and Sext 912 m2/g analyzed by SAA method. Mesoporous silica with 2% CTAB presented the best swelling ability with the ratio of 2.79, compared to 1% CTAB and 3% CTAB variations, which only showed swelling a ratio of 2.27 and 1.12, respectively."
Depok: Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Indonesia, 2024
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UI - Skripsi Membership  Universitas Indonesia Library
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Afif Zulfikar Pamungkas
"ABSTRAK
Karbon mesopori telah berhasil disintesis dengan metode soft template menggunakan phloroglucinol dan formaldehida sebagai sumber karbon dan Pluronic F127 sebagai template. Material kemudian diimpregnasi dengan Ni II dilanjutkan dengan reduksi dengan H2 sehingga terbentuk nanopartikel Ni yang terimpregnasi dalam karbon mesopori. Analisis dengan XRD menunjukkan difraksi pada 25 dan 44o yang merupakan difraksi dari karbon grafitik. Selain itu difraksi pada 45 dan 52o menunjukkan keberadaan Ni 0 . Analisis EDX mengungkap kandungan Ni dalam beberapa karbon mesopori sebesar 0,1 hingga 24 . Analisis luas permukaan memberi informasi karbon mesopori memiliki luas permukaan sebesar 387,7 m2/g dan pori 7,4 nm. Impregnasi dengan Ni akan memperkecil luas permukaan maupun ukuran pori. Analisis dengan XPS mengonfimasi keberadaan Ni dengan bilangan oksidasi nol. Material digunakan sebagai katalis untuk reaksi hidrogenasi CO2. Reaksi hanya dapat berlangsung jika terdapat Ni 0 sebagai pusat aktif pada karbon mesopori. Semakin banyak Ni 0 semakin besar konversinya meskipun tidak berpengaruh terhadap persen hasil yield . Konversi terbesar didapat dari katalis Ni-MC 30 dengan konversi dan yield berturut-turut 94,6 dan 3,5 pada suhu 673 K.

ABSTRACT
Mesoporous Carbon has been successfully synthesized via soft template method using phlroglucinol and formaldehyde as carbon precursors and Pluronic F127 as template. The material was impregnated with Ni II and reduced with H2 to obtainNi metal. XRD analysis showed diffraction peaks on 25 and 44o which are characteristic of graphitic carbon. In addition, diffraction on 45 and 52o showed the existence of Ni 0 . EDX analysis showed the Ni content in mesoporous carbon, that was 0.1 to 24 . Surface area analysis gave information about surface area of 387.7 m2 g and pore diameter of 7.4 nm. Ni impregnation is presumed to reduce both surface area and pore diameter of mesoporous carbon. XPS analysis confirmed zero oxidation state of Ni. This material was used as catalyst for CO2 hydrogenation reaction. This reaction gave product only in the presence of Ni. The higher the Ni content the higher the conversion though the yield is unchanged. The highest conversion is shown by Ni MC 30 with conversion of 94.6 and yield of 3.5 at 673 K."
Depok: Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Indonesia, 2018
T49910
UI - Tesis Membership  Universitas Indonesia Library
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Ahmad Ali Ibrahim
"ABSTRAK
Emisi CO2 telah meningkat secara dramatis dalam dekade terakhir yang menyebabkan efek samping pada lingkungan. Konversi CO2 menjadi senyawa kimia lain merupakan tantangan untuk mengurangi efek samping dari masalah ini. Ada beberapa teknik yang dapat mengurangi CO2 di alam seperti teknologi CCU (Carbon Capture and Utilization). Karbon mesopori yang memiliki luas permukaan besar dan ukuran pori dapat digunakan sebagai bahan penyerap CO2 dan bahan pendukung katalis. Ni metal memiliki beberapa keunggulan, seperti memiliki harga murah, aktivitas tinggi, dan berlimpah di alam. Dalam penelitian ini, efek karbon mesopori yang dimodifikasi oleh senyawa etilendiamin dan diimpregnasii dengan nanopartikel Ni (Ni @ EDA MC) sebagai katalis untuk hidrogenasi CO2 menjadi metana. Karbon mesopori yang dimodifikasi dikarakterisasi dengan FTIR, XRD, SEM-EDX, dan BET. Modifikasi proses hidrogenasi juga dilakukan (MC @ EDA) menggunakan ethylenediamine sebelum impregnasi. Dengan menggunakan katalis karbon mesopori yang diimpregnasi, CO2 dapat diserap dan dikonversi secara berurutan ke bahan kimia lainnya seperti metana. Katalis-katalis ini diuji dalam reaktor batch dengan variasi suhu (400, 500, dan 600oC), waktu (30, 60, 90 menit), dan jumlah katalis. Selanjutnya, analisis produk hidrogenasi menggunakan GC-TCD dengan menggunakan kolom porapak Q di bawah tekanan gas CO2 dan H2 masing-masing 1 bar.

ABSTRACT
The emissions of CO2 have been dramatically increased within the last decade causing the side-effects on the environment. Conversion of CO2 into other chemical compounds is a challenging to reduce the side-effect of these critical issues. There are some techniques that can reduce CO2 in nature such as CCU (Carbon Capture and Utilization) technology. Mesoporous carbon which has a large surface area and pore size can be used as CO2 adsorbent and catalyst support material. Ni metal has several advantages, such as having low prices, high activity, and abundant in nature. In this research, the effect of mesoporous carbon modified by ethylendiamine compound and impregnated with Ni nanoparticles (Ni@ EDA MC) as catalyst for the hydrogenation of CO2 to methane was investigated. Modified mesoporous carbon was characterized by FTIR, XRD, SEM-EDX, and BET. Modification of hydrogenation process was also carried out (MC@ EDA) using ethylenediamine before impregnation. By using impregnated mesoporous carbon catalysts, CO2 can be adsorbed and converted sequentially to other value added chemicals such as methane. These catalysts were tested in the batch reactor with variation of temperature (400, 500, and 600oC), time (30, 60, 90 minutes), and amount of catalyst. Furthermore, the analysis of hydrogenation product was carried out by GC-TCD using porapak Q column under CO2 and H2 gas pressure of 1 bar each.
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2019
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UI - Skripsi Membership  Universitas Indonesia Library
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Aulia Dyah Hutami Kawigraha
"Karbon mesopori telah disintesis dengan menggunakan metode soft-templating dengan menggunakan phloroglucinol sebagai prekursor karbon dan pluronic F127 sebagai template untuk membentuk pori dengan ukuran meso pada struktur karbon. Karbon mesopori kemudian diimpregnasi dengan logam nikel, dengan menggunakan Ni NO3 2. Setelah diimpregnasi, material selanjutnya diuji kemampuan katalisisnya untuk reaksi asetilen dengan CO2. Reaktor yang digunakan adalah lsquo;batch reactor rsquo; dari gelas kaca. Hasil BET membuktikan adanya hysteresis loop dan isotherm adsorpsi tipe IV dengan diameter pori sebesar 7,46 nm. Dengan instrumen EDX dibuktikan bahwa impregnasi nikel berhasil dengan masing-masing persen nikel untuk reduksi dengan etilen glikol pelarut air 34,48, etilen glikol pelarut air:etanol 0,02, NaBH4 0,9 dan gas H2 1,73. Pola XRD dari karbon mesopori yang direduksi dengan NaBH4 dan H2 menunjukan tidak ada perubahan pada struktur karbon mesopori, puncak 2 = 24,44 dan 43,18 hal ini membuktikan bahwa impregnasi logam tidak merubah struktur karbon mesopori. Pada uji aplikasinya, hasil analisa HPLC menunjukan puncak untuk baru pada waktu retensi 3,625 menit. Kondisi optimum didapatkan pada suhu 25 dan waktu 3 jam.

Mesoporous carbon has been synthesized using the soft templating method using phloroglucinol as carbon precursor and pluronic F127 as a template to form meso size pores on carbon structure. The mesoporous carbon is then impregnated with nickel metal, using Ni NO3 2. After impregnation, the material was further tested for its catalysis capacity for acetylene reactions with CO2. The reactor used is a 39 batch reactor 39 made of glass. The BET results prove the existence of hysteresis loop and IV type adsorption isotherm with a pore diameter of 7.46 nm. With EDX instrument it is proved that nickel impregnation succeeds with each percent of nickel, reduction using ethylene glycol with water as the solvent 34,48, ethylene glycol with water ethanol as the solvent 0,02, NaBH4 0,9 and H2 gas 1,73. XRD patterns of mesoporous carbon reduced with NaBH4 and H2 showed no change in mesoporous carbon structure, peak 2 24.44 and 43.18 This proves that metal impregnation does not alter the mesoporous carbon structure. In the application test, HPLC analysis shows a new peak at retention time of 3,625 minutes. The optimum condition was obtained at 25 and 3 hours.
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Depok: Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Indonesia, 2018
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UI - Skripsi Membership  Universitas Indonesia Library
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Hadi Rachman
"CO2 merupakan gas yang inert, tidak beracun, tidak mudah terbakar, dan menjadi gas penyumbang terbesar dalam efek rumah kaca yang menyebabkan suhu permukaan bumi naik. Di sisi lain, kelimpahannya yang tinggi di alam menjadikan CO2 sebagai sumber karbon yang potensial dalam sintesis fine chemicals. Dalam penelitian ini dilakukan studi reaksi karboksilasi fenilasetilena dengan CO2 menggunakan katalis logam Ni terimpregnasi pada support karbon mesopori. Karbon mesopori telah berhasil disintesis dengan metode soft template menggunakan Pluronik F127 sebagai pembentuk pori, formaldehida dan phloroglucinol sebagai sumber karbon, dan HCl sebagai katalis asam. Material ini dikarakterisasi dengan FTIR, XRD, SEM, dan BET. Spektra FTIR dari karbon mesopori sebelum karbonisasi memiliki puncak serapan 3500 2800 cm-1 yang menunjukkan adanya stretching C-H dan stretcing O-H dari phloroglucinol dan formaldehida. Sedangkan setelah karbon mesopori dikarbonisasi, puncak serapan pada bilangan gelombang tersebut hilang. Karakterisasi dengan XRD menunjukkan adanya dua puncak pada 2 yakni 24,26o dan 42,76o yang menandakan puncak khas dari karbon mesopori. Analisis luas permukaan dengan BET menghasilkan isoterm adsorpsi N2 pada karbon mesopori yang menunjukkan adanya hystersis loop pada rentang P/Po sekitar 0,4-0,9 yang merupakan karakter dari karbon mesopori. Karbon mesopori hasil sintesis memiliki distribusi ukuran pori sebesar 7.2 nm yang termasuk dalam rentang material mesopori 2-50 nm . Karakterisasi dengan SEM menunjukkan bentuk yang datar dengan ukuran kristal beragam. Modifikasi support dilakukan dengan cara impregnasi logam Ni ke dalam karbon mesopori Ni@MC . Katalis Ni@MC digunakan sebagai katalis dalam reaksi karboksilasi fenilasetilena dengan CO2. Reaksi dilakukan dalam reaktor batch dengan kondisi reaksi yang bervariasi, yakni suhu 25oC, 50oC, 85oC dan waktu 8 jam, 12 jam, dan 16 jam. Hasil analisis campuran produk dengan HPLC menunjukkan terbentuknya asam sinamat sebesar 1,52 pada sampel 85oC 8jam, 2,83 pada sampel 85oC 12jam, dan 0,62 pada sampel 85oC 16jam.

CO2 is an inert, non toxic, non flammable, and the largest contributor gas to greenhouse gases causing the earth 39 s surface temperature to rise. Its high abundance in nature makes CO2 a potential carbon source in fine chemical synthesis. In this research, carboxylation reaction of phenylacetylene with CO2 has been studied using an impregnated nickel catalyst on mesoporous carbon support. Mesoporous carbon has been successfully synthesized by soft template method using Pluronic F127 as pore forming, formaldehyde and phloroglucinol as carbon source, and HCl as acid catalyst. This material was characterized by FTIR, XRD, SEM, and BET analysis. The FTIR spectra of the mesoporous carbon before carbonization had an absorption peak of 3500 2800 cm 1 indicating the presence of stretching C H and stretching O H of phloroglucinol and formaldehyde. Meanwhile after carbonization, those peaks disappear. Characterization with XRD shows the presence of two peaks at 2 24.26 and 42.76 which denotes the typical peak of mesoporous carbon. BET Surface Area Analysis gave N2 adsorption isotherm on mesoporous carbon indicating a hysterysis loop in the P Po range 0.4 0.9 which is a character of mesoporous carbon. Synthesized mesoporous carbon had pore size distribution of 7.2 nm which is included in the mesoporous material range 2 50 nm . Characterization with SEM shows a flat shape with varying crystal sizes. Modification of support has been conducted by impregnation of Ni metal into mesoporous carbon Ni MC . The Ni MC catalyst was used as a catalyst in the carboxylation reaction of phenylacetylene with CO2. The reactions were carried out in a batch reactor under various reaction conditions at reaction temperature of 25oC, 50oC, and 85oC and for over 8, 12, and 16 hours. HPLC analysis of the product mixtures shows that cinnamic acid was formed with 1,52 yield in 85oC 8h sample, 2,83 yield in 85oC 12h sample, and 0,62 yield in 85oC 16h sample.
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Depok: Fakultas Matematika Dan Ilmu Pengetahuan Alam Universitas Indonesia, 2018
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UI - Skripsi Membership  Universitas Indonesia Library
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Tania Priantini
"Material karbon mesopori berhasil disintesis melalui metode soft template dengan menggunakan formaldehida dan floroglusinol sebagai sumber karbon, pluronic F127 sebagai SDA, dan asam klorida sebagai katalis. Dilakukan pengujian awal terhadap karbon mesopori hasil sintesis sebagai adsorben zat warna Acid Red 119. Proses sintesis karbon mesopori melibatkan reaksi polimerisasi formaldehida dengan floroglusinol pada soft template F127 dalam pelarut etanol:air. Analisis termal gravimetri menunjukkan kestabilan termal karbon mesopori hingga mencapai suhu 900 0C. Karakterisasi dengan XRD menunjukkan adanya dua puncak pada 2θ = 22,020 dan 2θ = 42,420 yang menandakan material karbon. Isoterm adsorpsi N2 pada karbon mesopori menunjukkan adanya hystersis loop pada rentang P/P0 sekitar 0,45-0,85 yang merupakan karakter dari padatan mesopori. Karbon mesopori hasil sintesis memiliki ukuran diameter pori yang seragam, yaitu sebesar 8,863 nm. Karakterisasi dengan SEM menunjukkan bentuk grass-like dengan ukuran yang seragam. Variasi kondisi adsorpsi yaitu konsentrasi awal, pH, dan waktu kontak dilakukan untuk menentukan kondisi optimum adsorpsi Acid Red 119 pada karbon mesopori. Kondisi optimum adsorpsi Acid Red 119 dengan menggunakan 10 mg karbon mesopori tercapai pada pH 3 dengan waktu kontak selama 60 menit dan kosentrasi awal larutan sebesar 200 ppm. Karbon mesopori hasil sintesis memiliki kapasitas adsorpsi (Qe) sebesar 217,7389 mg/g. Pemodelan isoterm adsorpsi Freundlich sangat sesuai untuk menjelaskan proses adsorpsi zat warna Acid Red 119 pada karbon mesopori dengan nilai konstanta Freundlich (Kf) sebesar 9,8946 L/g. Daya adsorpsi karbon mesopori hasil sintesis lebih besar dibandingkan karbon aktif komersial, yaitu 1,53 kali lipat.

Mesoporous carbon material was successfully synthesized through soft-template method by using formaldehyde and phloroglucinol as carbon sources, pluronic F127 as SDA, and hydrochloric acid as catalyst. Preliminary test as adsorbent was carried out to adsorption of Acid Red 119 dyes. The synthesis process of mesoporous carbon involved polymerization of formaldehyde with phloroglucinol in soft-template F127 with the mixture of ethanol and water solvent. The thermogravimetric analysis showed resulted mesoporus carbon is stable up to 900 0C. XRD characterization resulted two identity peaks at 2θ = 22.020 and 2θ = 42.420 as the evidence of carbon material structure. The isotherm of N2 adsorption in mesoporous carbon exhibited hysterisis loop in P/P0 of 0.45-0.85 range which indicates the character of mesoporous solid material. This material has homogeneous pore sizes of 8.863 nm. SEM images showed the uniform grass-like structures on the surface of the bulk carbon. Adsorption conditions, i.e. contact time, intial dye concentration, and pH solution were studied to evaluate the optimum condition of Acid Red 119 adsorption onto mesoporous carbon. The optimum condition of Acid Red 119 adsorption using 10 mg of mesoporous carbon was reached at pH 3 for 60 minutes and 200 ppm of initial dye concentration. The adsorption capacity (Qe) of synthesized mesoporous carbon reaches 217.7389 mg/g. The adsorption of Acid Red 119 into mesoporous carbon can be described by Freundlich isotherm adsorption with the Freundlich constant (Kf) value of 9.8946 L/g. Adsorption capacity of mesoporous carbon is 1.53 times higher than that of commercial activated carbon.
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Depok: Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Indonesia, 2014
S56896
UI - Skripsi Membership  Universitas Indonesia Library
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Riri Andriyanti
"Carbon dioxide is a renewable C1 resource for synthesis chemicals. CO2 in carboxylation reactions requires catalysts Ni complex for CO2 activation. However, the use of Ni complex homogeneous catalysts in the reaction is still less efficient due to the difficult in separating the product and catalyst. Therefore, it is necessary to heterogenize the Ni complex in solid supporting such as mesoporous carbon. In this research, a carboxylation reaction with CO2 was tested using a Ni catalyst that was functionalized with phenanthroline (phen) ligand impregnated on the solid support of mesoporous carbon. Soft template method has been successfully used in mesoporous carbon synthesis with phloroglucinol and formaldehyde prekursors as a carbon source, Pluronic F127 as a structural directing agent, and HCl as an acid catalyst. Modification of the catalyst was carried out by impregnation of Ni from Ni(NO3)2.6H2O which was then functionalized with phenanthroline (phen) ligands into mesoporous carbon to form Ni-phen/MC catalysts. Mesoporous carbon material (MC) and Ni-phen/MC are characterized by FT-IR, XRD, SEM-EDX, and SAA. The results of SAA characterization showed that the pore diameter of MC was 6.7174 nm and Ni-phen/MC was 5.08 nm which indicate that the material was mesoporous. Ni-phen/MC material was then used as a heterogeneous catalyst in the carboxylation reaction of phenylacetylene with CO2. The reaction were carried out in several variations of conditions, temperature variations (25oC, 50oC and 75oC), time variations (4 hours, 8 hours and 16 hours), variations in catalyst types (MC, Ni-phen and Ni-phen/MC). Based on the results of the reaction, the optimum conditions was obtained at 25oC for 8 hour of reaction time using Ni-phen/MC catalyst. The main product of the carboxylation reaction is identified by the HPLC instrument, while the remaining catalyst that has been used in the reaction was identified using the FT-IR instrument.
Carbon dioxide is a renewable C1 resource for synthesis chemicals. CO2 in carboxylation reactions requires catalysts Ni complex for CO2 activation. However, the use of Ni complex homogeneous catalysts in the reaction is still less efficient due to the difficult in separating the product and catalyst. Therefore, it is necessary to heterogenize the Ni complex in solid supporting such as mesoporous carbon. In this research, a carboxylation reaction with CO2 was tested using a Ni catalyst that was functionalized with phenanthroline (phen) ligand impregnated on the solid support of mesoporous carbon. Soft template method has been successfully used in mesoporous carbon synthesis with phloroglucinol and formaldehyde prekursors as a carbon source, Pluronic F127 as a structural directing agent, and HCl as an acid catalyst. Modification of the catalyst was carried out by impregnation of Ni from Ni(NO3)2.6H2O which was then functionalized with phenanthroline (phen) ligands into mesoporous carbon to form Ni-phen/MC catalysts. Mesoporous carbon material (MC) and Ni-phen/MC are characterized by FT-IR, XRD, SEM-EDX, and SAA. The results of SAA characterization showed that the pore diameter of MC was 6.7174 nm and Ni-phen/MC was 5.08 nm which indicate that the material was mesoporous. Ni-phen/MC material was then used as a heterogeneous catalyst in the carboxylation reaction of phenylacetylene with CO2. The reaction were carried out in several variations of conditions, temperature variations (25oC, 50oC and 75oC), time variations (4 hours, 8 hours and 16 hours), variations in catalyst types (MC, Ni-phen and Ni-phen/MC). Based on the results of the reaction, the optimum conditions was obtained at 25oC for 8 hour of reaction time using Ni-phen/MC catalyst. The main product of the carboxylation reaction is identified by the HPLC instrument, while the remaining catalyst that has been used in the reaction was identified using the FT-IR instrument."
Depok: Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Indonesia, 2019
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