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"Karbondioksida merupakan gas rumah kaca yang menjadi salah satu faktor pemanasan global dan perubahan iklim secara drastis. Namun, di samping dampak negatif emisi gas CO2 secara alami maupun melalui hasil kegiatan antropogenik, CO2 dapat dimanfaatkan sebagai sumber C1 reaksi organik, salah satunya reaksi karboksilasi. Periodic Mesoporous Organosilica (PMO) merupakan material mesopori silika yang memiliki keunggulan, di antaranya memiliki ukuran pori cukup besar yang dapat memfasilitasi transfer massa dengan baik, luas permukaan besar yang memungkinkan banyak sisi katalitik, maupun integrasi dari spesi organik dan atom logam dalam kerangka PMO. Logam nikel merupakan logam yang secara luas digunakan dalam bidang katalisis, karena logam tersebut memiliki orbital d tidak terisi penuh, sehingga dapat membentuk ikatan kovalen koordinasi dan memudahkan proses pembentukan intermediet pada permukaan katalis. Pada penelitian ini, dilakukan sintesis PMO dengan prekursor 4,4’- bis(trietoksisilil)bifenil dan dilanjutkan dengan fungsionalisasi gugus amina melalui proses nitrasi dan aminasi. Selanjutnya, dilakukan imobilisasi kompleks Ni(acac)2 pada material Bph-PMO untuk digunakan sebagai katalis pada reaksi karboksilasi fenilasetilena dengan CO2. Analisis XRD menunjukkan bahwa fungsionalisasi gugus amina pada Bph-PMO tidak merubah komponen maupun struktur periodik pada Bph-PMO, begitu pula setelah nikel diimobilisasi pada Bph- PMO yang terfungsionalisasi gugus amina. Analisis FTIR Ni/NH2-Bph-PMO menunjukkan puncak serapan pada 1605 cm-1 yang mengindikasikan pembentukan ikatan C=N dari reaksi kondensasi Schiff antara gugus amina dengan C=O pada Ni(acac)2. Material Ni/NH2-Bph-PMO memiliki ukuran partikel rata-rata 420 nm, dengan pemuatan nikel 2,8% berdasarkan analisis SEM-EDX. Analisis TEM menunjukkan keberadaan struktur mesopori pada NH2-Bph-PMO. Ukuran diameter pori dan luas permukaan BET material Ni/NH2-Bph-PMO berturut-turut sebesar 3,16578 nm dan 490,742 m2/g. Uji katalitik material Ni/NH2-Bph-PMO pada karboksilasi fenilasetilena dengan CO2 dilakukan pada tiga variasi suhu, di mana kondisi optimum diperoleh pada suhu 25 °C, dengan konsentrasi produk fenil maleat 244,5899 ppm.

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ABSTRACTCarbon dioxide is a greenhouse gas that affecting global warming and produces climate change. However, aside from the negative effects of natural CO2 gas emissions and through anthropogenic activities, CO2 has been used as a source of C1 organic reactions, for example, carboxylation reaction. Periodic Mesoporous Organosilica (PMO) is a superior silica mesoporous material, which has a large pore to facilitate mass transfer, a large area that allows many catalytic sides, which also associated with organic species and metal atoms in PMO. This property supports PMO to be applied as a metal catalyst support. Nickel metal is a metal that is widely used in the catalysis field, because this metal has d orbitals and is not fully filled, so it can form covalent bonds and fasilitate process of making intermediates on the surface of the catalyst. In this study, PMO was synthesized with 4,4'-bis (triethoxysilyl) biphenyl precursor and continued with the functionalization of amine groups through nitration and amination process. Furthermore, immobilization of Ni(acac)2 complex was carried out on the Bph-PMO material to be used as a catalyst in the carboxylation reaction of phenylacetylene with CO2. Analysis of XRD shows that the functionalization of amine groups on Bph-PMO does not change the periodic structure of Bph-PMO, as well as after nickel immobilized on aminated Bph-PMO. Absorption peak at 1605 cm-1 of Ni/NH2- Bph-PMO revealed from FTIR analysis, indicating new C=N bond from Schiff condensation between amine group and C=O from Ni(acac)2. Ni/NH2-Bph-PMO material has an average particle size of 420 nm, with 2,8% nickel loading based on SEM-EDX analysis. Mesoporous structure of NH2-Bph-PMO has been proved by TEM analysis. The pore diameter size and BET surface area of Ni/NH2-Bph-PMO are 3,16578 nm and 490,742 m2/g, respectively. The catalytic test of Ni/NH2-Bph- PMO on phenylacetylene carboxylation with CO2 was carried out at three temperature variations, which shows that optimum condition was obtained at 25 °C, with a concentration of phenyl maleic product of 244,5899 ppm."

"ABSTRAKKarbon dioksida (CO2) merupakan senyawa yang potensial digunakan sebagai sumber karbon dalam sintesis fine chemicals karena keberadaannya melimpah di alam, bersifat non toksik, ekonomis, dan termasuk ke dalam sumber yang dapat diperbaharui. Namun pemanfaatan CO2 secara luas masih terkendala karena sifatnya yang inert dan stabil. Oleh karena itu, keberadaan katalis sangat diperlukan dalam proses konversi CO2. Penelitian ini bertujuan untuk mensintesis Cu terimpregnasi pada karbon mesopori sebagai katalis karboksilasi fenilasetilena dengan CO2 menjadi asam karboksilat. Pembuatan karbon mesopori dilakukan dengan metode soft template menggunakan Pluronik F-127 sebagai pembentuk pori, formaldehida dan floroglusinol sebagai sumber karbon, dan HCl sebagai katalis asam. Material Cu/MC yang dihasilkan dikarakterisasi dengan FTIR, XRD, SAA, dan SEM-EDX. Analisis BET terhadap karbon mesopori menunjukkan bahwa material tersebut memiliki luas permukaan sebesar 405,8 m2/g dengan rata-rata pori sebesar 7,2 nm. Hasil analisa dengan XRD memperlihatkan puncak pada 2θ 36,62°; 43,47°; 50,63°; dan 74,19° yang mengindikasikan bahwa Cu telah berhasil terimpregnasi yang mewakili spesi Cu(0) dan Cu(I). Reaksi karboksilasi fenilasetilena dengan CO2 dilakukan dengan variasi suhu (25°C; 50°C; dan 75°C), variasi jumlah katalis (28,6; 57,2; dan 85,8 mg) dan variasi basa (Cs2CO3; K2CO3; dan Na2CO3). Hasil reaksi dianalisa dengan HPLC dan memperlihatkan %konversi terbaik terjadi pada suhu 75°C yaitu 41,32% dengan menggunakan Cs2CO3 sebagai basa, dan produk yang terbentuk diidentifikasi dengan FTIR dan LC-MS.

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ABSTRACTCarbon dioxide (CO2) is a compound that has the potential to be used as carbon source in the synthesis of fine chemicals because it is abundant in nature, non-toxic, inexpensive, and is included as a renewable source. However, utilization of CO2 is stillconstrained due to its inert and stable nature. Therefore, the presence of a catalyst is needed in CO2 conversion. This study aims to synthesize impregnated Cu on mesoporous carbon (Cu/MC) as a catalyst for phenylacetylene carboxylation reaction with CO2 into carboxylic acid. The synthesis of mesoporous carbon was performed via soft template method using Pluronic F-127 as a pore forming agen, formaldehyde and phloroglucinol as carbon sources, and HCl as an acid catalyst. The Cu/MC material produced was characterized by FTIR, SAA, XRD, and SEM-EDX. BET surface area analysis of mesoporous carbon showed that the material has a surface area of 405.8 m2/g with an average pore diameter of 7,2 nm. XRD pattern of Cu/MC showed some sharp peaks at 2θ of 36.62°; 43.47°; 50.63°; and 74.19° which indicates that Cu has been successfully impregnated in the form of Cu(0) and Cu(I). Phenylacetylene carboxylation reaction with CO2 was carried out by varying reaction temperatures (25, 50, and 75 °C), the amount of catalyst (28.6, 57.2, and 85.8 mg) and the type of base (Cs2CO3, K2CO3, and Na2CO3). The reaction mixtures were analyzed by HPLC and showed that highest phenylacetylene conversion of 41% was obtained for the reaction at 75°C using Cs2CO3 as a base. The product was further identified using FTIR and LCMS."

"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."

"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.

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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."

"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 %.

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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%."

"Studi perbandingan katalis Cu/CeO2/Al2O3 dan Cu/ZnO/Al2O3 menjadi topik menarik untuk diteliti karena memiliki perbedaan konversi dan selektifitas terhadap produk alkohol. Katalis Cu/CeO2/Al2O3 dan Cu/ZnO/Al2O3 berhasil disintesis dan diuji kinerja katalisisnya dalam reaktor dengan perbandingan laju alir CO2:H2 sebesar 1:3 dengan suhu 250oC, 300oC dan 350oC. Penelitian ini bertujuan untuk melihat efektifitas dari kedua katalis dalam menghasilkan metanol dan ingin diketahui pengaruh pemberian beberapa variasi suhu. Hasil sintesis katalis dikarakterisasi menggunakan instrument SEM, XRD dan BET. Hasil reaksi hidrogenasi juga dikarakterisasi menggunakan VOC meter, IRGA dan GC-MS. Produk hasil hidrogenasi CO2 menggunakan katalis Cu-CeO2 menunjukkan konsentrasi senyawa organik secara beturut sebesar 4,7 ppm, 8,6 ppm dan 10,1 ppm dengan CO2 terkonversi sebesar 81,68%, 87,35% dan 90,14%, serta kromatogram GC-MS mengindikasikan senyawa metanol. Sedangkan dengan penggunaan katalis Cu-ZnO, didapatkan konsentrasi senyawa organik berturut sebesar 0,5 ppm, 1,0 ppm dan 2,4 ppm dengan CO2 terkonversi sebesar 81,46%, 81,58% dan 84,16%. Hasil tersebut menunjukan bahwa katalis Cu/CeO2/Al2O3 lebih efektif dalam menghidrogenasi CO2 menjadi metanol.

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Comparative studies of Cu/CeO2/Al2O3 and Cu/ZnO/Al2O3 catalysts is an interesting topic to research because of the differences of their conversion rates and selectivity to produce alcohol. Cu/CeO2/Al2O3 and Cu/ZnO/Al2O3 catalysts were successfully synthesized and the performances has been tested in a reactor with the ratio flow rate of CO2:H2 which is 1:3 temperatures of 250oC, 300oC dan 350oC. This study aimed to determine the abilities of both catalyst in producing metanol and to find the effect of several temperature variations. The characterizations of the synthesized catalysts were performed using SEM, XRD and BET instruments. The results of the hydrogenation reaction were also characterized using a VOC meter, IRGA and GC-MS. Products resulting from hydrogenation of CO2 using a Cu-CeO2 catalyst showed concentrations of organic compounds of 4.7 ppm, 8.6 ppm and 10.1 ppm with converted CO2 of 81.68%, 87.35% and 90.14% and GC-MS chromatograms indicates a methanol compound. Meanwhile, with the use of Cu-ZnO catalyst, the concentration of organic compounds was obtained, respectively, 0.5 ppm, 1.0 ppm and 2.4 ppm with converted CO2 of 81.46%, 81.58% and 84.16%. These results indicate that the Cu/CeO2/Al2O3 catalyst is more effective in hydrogenating CO2 into methanol."

"Sintesis Periodic Mesoporous Organosilica dengan jembatan biphenylene telah berhasil dilakukan menggunakan metode sol gel dengan kehadiran surfaktan sebagai template. Selanjutnya fungsionalisasi Bph-PMO dengan gugus amina telah berhasil dilakukan dengan dua langkah reaksi kimia yaitu reaksi nitrasi menggunakan HNO3 65%/H2SO4 96% dan reduksi menggunakan menggunakan SnCl2/HCl 37%. Hasil sintesis kemudian dikarakterisasi menggunakan FTIR, XRD, dan TEM EDX. Karakterisasi TEM mengkonfirmasi struktur material Bph-PMO memiliki struktur mesopori 2D hekasogonal dengan periodisitas molekuler, setelah difungsionalisasi dengan ukuran rata-rata diamater partikel sebesar 223.7 nm. Modifikasi permukaan pada NH2-Bph-PMO dengan nanopartikel perak telah dilakukan dengan metode impregnasi dan reduksi menggunakan AgNO3 sebagai prekursor perak dan NaBH4 sebagai agen pereduksi. Hasil karakterisasi XRD mengkonfirmasi keberadaan nanopartikel perak pada nilai 2θ = 38.1o, 44.2o, 64.5o dan 77,4o. Perhitungan besar ukuran kristal rata-rata dari nanopartikel perak dalam Ag/NH2-Bph-PMO adalah 8,05 nm berdasarkan persamaan Debye- Scherer. Kemampuan adsorpsi CO2 pada material Bph-PMO, NH2-Bph-PMO dan Ag/NH2-Bph-PMO ditentukan menggunakan metode titrimetri. Banyaknya CO2 yang teradsorpsi selama 15 menit dari masing masing material adalah 33.44, 8.392, dan 16.4 mmol. Reaksi karboksilasi fenilasetilena dengan CO2 dilakukan dengan variasi suhu (25oC, 50oC, dan 70oC). Hasil reaksi dianalisa menggunakan HPLC dan menunjukkan %konversi terbaik pada suhu 50oC yaitu 46.74%.

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Synthesis of Biphenyl Periodic Mesoporous Organosilica (Bph-PMO) has been successfully carried out using the sol gel method in the presence of surfactants as a template. Furthermore, the functionalization of Bph-PMO with an amine group has been successfully carried out with two steps of a chemical reaction, nitration reaction (HNO3 65%/H2SO4 96%) and reduction (SnCl2/HCl 37%). Results of the synthesis were characterized using FTIR, XRD, and TEM EDX. TEM characterization confirmed that Bph-PMO material having a 2D hekasogonal mesoporous structure with molecular periodicity, after functionalized the material have average particle size of 223.7 nm. Surface modification of NH2-Bph-PMO with silver nanoparticles has been carried out by impregnation and reduction method using AgNO3 as a silver precursor and NaBH4 as a reducing agent. The result of XRD characterization confirmed the presence of silver nanoparticles at 2θ = 38.1o, 44.2o, 64.5o and 77.4o. Based of Debye-Scherer Calculation the average crystal size of silver nanoparticles in Ag/NH2-Bph-PMO is 8.05 nm. The capacity adsorption of CO2 on Bph-PMO, NH2-Bph-PMO and Ag/NH2-Bph-PMO materials was determined using the titrimetry method. The amount of CO2 adsorbed for 15 minutes from each material is 33.44, 8,392 and 16.4 mmol. The carboxylation reaction of phenyl acetylene with CO2 was carried out with variation of temperature (25oC, 50oC, and 70oC). The results of the reaction were analyzed using HPLC and showed the best conversion at 50oC at 46.74%."

"Pemanasan global dan perubahan iklim merupakan isu lingkungan terbesar pada abad ke-21 yang mengakibatkan emisi gas CO2 yang terus meningkat setiap tahunnya. Peningkatan emisi gas CO2 yang disebabkan oleh aktivitas manusia menyebabkan upaya pengurangan emisi terus dilakukan. Reaksi hidrogenasi merupakan salah satu reaksi yang dapat dilakukan untuk mengubah CO2. Sifat CO2 yang stabil secara termodinamik dan inert menyebabkan katalis digunakan untuk mempermudah reaksi. Katalis berbasis nikel merupakan katalis yang banyak digunakan menggantikan katalis logam mulia untuk hidrogenasi CO2. Pada penelitian ini, katalis NiSn tersangga oleh karbon mesopori (NiSn/MC) disintesis untuk mengkonversi CO2 menjadi formaldehida dan metanol melalui reaksi hidrogenasi. Pola difraksi NiSn/MC menunjukkan puncak pada 26.02°; 28,6°; 33,8°; 42,5°; 44,9°; 59,2°; 71,2°; 79,5°; 86,6°. yang merupakan puncak difraksi dari grafit dan NiSn. Karakterisasi SEM-EDX mapping dan TEM menunjukkan partikel NiSn tersebar merata pada permukaan karbon mesopori dan tidak membentuk klaster tersendiri. Berdasarkan hasil reaksi yang dilakukan, material Ni5Sn1/MC memberikan konversi CO2 tertinggi sebesar 39.86% dibandingkan Ni1Sn1/MC, Ni3Sn1/MC, Ni/MC, Sn/MC, dan NiSn NPs. Yield metanol Ni5Sn1/MC sebesar 86.31 mmol/gcat. Kondisi optimum untuk reaksi hidrogenasi CO2 didapat pada temperatur 175°C dengan rasio gas CO2:H2 sebesar 1:7.

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Global warming and climate change are the biggest environmental issues in the 21st century due to the increase of CO2 emissions in the atmosphere. The increasing CO2 emissions has led to continuing efforts to reduce CO2 levels. One of the methods to reduce CO2 emission is to convert CO2 through chemical reactions such as the hydrogenation reaction into more valuable chemicals. The nature of CO2 which is stable and inert causes the reaction of CO2 needs to be facilitated by a catalyst. This research synthesized NiSn nanoparticles on mesoporous carbon (NiSn/MC) to convert CO2 into formaldehyde and methanol. The diffraction patterns of NiSn/MC exhibit peaks at 26.02°, 28,6°; 33,8°; 42,5°; 44,9°; 59,2°; 71,2°; 79,5°; 86,6° which correspond to diffraction peaks of graphite and NiSn. SEM-EDX Mapping and TEM characterization reveal that NiSn are uniformly dispersed on the mesoporous carbon surface and do not form distinct clusters. Based on the conducted reactions, Ni5Sn1/MC demonstrated the highest CO2 conversion of 39.86% compared to Ni1Sn1/MC, Ni3Sn1/MC, Ni/MC, Sn/MC, and NiSn NPs. The methanol yield of CO2 hydrogenation with Ni5Sn1/MC is 86.31 mmol/gcat. The optimum conditions for the CO2 hydrogenation reaction were achieved at a temperature of 175°C and CO2:H2 gas ratio of 1:7."

"ABSTRACTKarbon dioksida (CO2) adalah gas rumah kaca utama yang menyebabkan pemanasan global dan perubahan iklim. Karena jumlahnya yang melimpah, CO2 dapat dijadikan sebagai sumber C1 terbarukan untuk sintesis bahan kimia yang berguna. Dalam penelitian ini, telah 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. 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 dengan kondisi reaksi yang bervariasi, yakni variasi jenis pelarut (DMF dan Toluene), variasi tekanan (1 atm, 3 atm, 5 atm), variasi suhu (85oC, 100oC, 125oC). Produk reaksi karboksilasi ini yang diharapkan merupakan asamsinamat yang kemudian dianalisis dengan menggunakan HPLC untuk menentukan %yield dan %konversi.

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ABSTRACTCarbon dioxide (CO2) is the main greenhouse gas that causes global warming and climate change. Due to its abundance, CO2 can be used as a renewable C1 source for the synthesis of useful chemicals. In this research, carboxylation reaction of phenylacetylene with CO2 has been carried out using nickel impregnated in mesoporous carbon as catalyst support. Mesoporous carbon has been successfully synthesized using soft template method with Pluronik F127 as a pore-forming, formaldehyde and phloroglucinol as carbon source, and HCl as acid catalyst. Material was characterized by FTIR, XRD, SEM, and BET. Modification of support was done by impregnating nickel into mesoporous carbon (Ni@MC). Ni@MC was then used as a catalyst in carboxylation reaction of phenylacetylene with CO2. The reactions were carried out in reactor with various conditions, such as temperature (85oC, 100oC, 125oC), solvent (DMF and Toluene), and pressure (1 atm, 3 atm, 5 atm). The result of carboxylation reactions which is expected to be cinnamic acid, were analyzed by HPLC and LC MS to determine yield and conversion."

"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."