Hasil Pencarian  ::  Simpan CSV :: Kembali

"Karbon dioksida (CO2) salah satu komponen utama gas rumah kaca yang merupakan penyumbang total terbesar terhadap perubahan iklim. Oleh karena itu, perlu dilakukan pengurangan emisi gas CO2, baik dengan menyimpan maupun memanfaatkan CO2 sebagai sumber penghasil bahan kimia yang lebih bermanfaat melalui reaksi katalitik heterogen. Dalam penelitian ini, Ni(0) yang disangga pada karbon mesopori (MC) digunakan sebagai katalis untuk mengonversi CO2 menjadi gas metana dalam reaksi Sabatier. Karbon mesopori berhasil disintesis dengan metode cetakan lunak menggunakan phloroglucinol, Pluronic F127, dan formaldehida sebagai prekursor. Karbon mesopori hasil sintesis dikarakterisasi menggunakan instrumen FTIR, XRD, SEM-EDS, TEM, SAA, dan Raman kemudian dimodifikasi menggunakan nanopartikel Ni(0) dari prekursor Ni(NO3)2.6H2O dan Ni(acac)2 dalam jumlah tertentu. Katalis Ni(0)/MC yang disintesis kemudian diberi label sebagai Ni/MC(5)(Ni(NO3)2) dan Ni/MC(30)(Ni(NO3)2) untuk 5% dan 30% Ni(0) dari Ni(NO3)2.6H2O dan Ni/MC(30)(Ni(acac)2) untuk 30% Ni(0) dari Ni(acac)2. Katalis Ni(0)/MC dikarakterisasi menggunakan instrumen FTIR, XRD, SEM-EDS, TEM, SAA, dan Raman. MC dan Ni(0)/MC hasil sintesis digunakan sebagai katalis untuk reaksi konversi CO2 menjadi CH4 menggunakan tubular furnace pada T = 873 K selama 9 menit. Produk hasil reaksi diukur menggunakan kromatografi gas dengan detektor TCD. %yield produk dari hasil reaksi adalah 0%; 1,33%; 1,63%; dan 1,9% untuk MC, Ni/MC(5)(Ni(NO3)2), Ni/MC(30)(Ni(NO3)2), dan Ni/MC(30)(Ni(acac)2). Hasil penelitian menunjukkan bahwa %yield setelah percobaan ke-2, ke-3, dan ke-4 secara bertahap menurun. Hasil ini menunjukkan bahwa nanopartikel Ni(0) memiliki peran penting untuk mengaktifkan CO2 serta penurunan kapasitas reaksi seiring dengan pengujian berkala dapat disebabkan oleh transformasi Ni(0) menjadi nanopartikel Ni(II).

---

Carbon dioxide (CO2), a major component of greenhouse gases, is the largest total contributor to the climate change. Therefore, it is necessary to reduce the CO2 gas emissions, either by storing or utilizing CO2 as a source to produce value-added chemicals through heterogenous catalytic reactions. In this work, Ni(0) supported on mesoporous carbon (MC) was used as catalyst to convert CO2 to methane gas in Sabatier reaction. Mesoporous carbon was successfully synthesized by a soft template method using phloroglucinol, Pluronic F127 and formaldehyde as precursors. The as-synthesized mesoporous carbon was characterized using FTIR, XRD, SEM-EDS, TEM, SAA, and Raman instruments and then modified with Ni(0) nanoparticles using certained amount of Ni(NO3)2.6H2O or Ni(acac)2 as precursor. The prepared Ni(0)/MCs then were label as Ni/MC(5)(Ni(NO3)2) and Ni/MC(30)(Ni(NO3)2) for 5% and 30% Ni(0) from Ni(NO3)2.6H2O, and Ni/MC(30)(Ni(acac)2) for 30% Ni(0) from Ni(acac)2, respectively. The Ni(0)/MC catalysts was characterized using FTIR, XRD, SEM-EDS, TEM, SAA, and Raman instruments. Both as-synthesized MC and Ni(0)/MC then used as the catalysts for CO2 conversion reaction to CH4 using tubular furnace at T = 873 K for 9 minutes. The product reaction was measured using gas-chromatography with thermal conductivity detector. The % yield of products from reaction are 0%; 1.33%; 1.62%; and 1.9% for MC, Ni/MC(5)(Ni(NO3)2), Ni/MC(30)(Ni(NO3)2) and Ni/MC(30)(Ni(acac)2) respectively. The CO2 conversion reaction capacity was also conducted using Ni/MC(30)(Ni(acac)2) to evaluate the catalyst performance. The results shows that the % yield of the reaction after 2nd, 3rd, and 4th attempt were gradually decreased. These results shows that Ni(0) nanoparticles have an important role for activating the CO2 and the decreases of the reaction capacity along periodic test may be caused by the transformation of Ni(0) into Ni(II) nanoparticles."

"Kenaikan sejumlah besar CO₂ mengakibatkan konsentrasi CO₂ semakin meningkat di atmosfer secara terus-menerus yang menyebabkan terjadinya perubahan iklim. Pengembangan reaksi katalitik terbarukan diperlukan untuk mentransformasi CO₂ menjadi produk yang lebih bermanfaat. Pada penelitian ini, telah dilakukan uji reaksi karboksilasi fenilasetilena dengan CO₂ menggunakan katalis Ni(acac)₂, NiCl₂ dan Ni(DBU)₂ yang terimpregnasi pada penyangga karbon mesopori. Material karbon mesopori, Ni(acac)₂/ MC, NiCl₂/ MC dan Ni(DBU)₂/ MC dikarakterisasi dengan FT-IR, XRD, SAA dan SEM-EDS. Karbon mesopori telah berhasil disintesis menggunakan metode soft template dibuktikan dengan hasil  analisa XRD yang menunjukkan pola difraksi secara khas pada material karbon pada 25,68^o dan 43,26^o dengan indeks Miller (002) dan (100). Proses impregnasi  pada Ni(acac)₂, NiCl₂ dan Ni(DBU)₂  pada penyangga karbon mesopori telah berhasil ditunjukkan dengan analisa FT-IR dimana pada spektrum Ni(acac)₂/ MC, NiCl₂/ MC dan Ni(DBU)₂/ MC menghasilkan spektrum yang sama dengan MC dikarenakan senyawa terimpregnasi telah masuk ke dalam pori sehingga mengakibatkan tidak terdeteksinya gugus fungsi yang ada pada senyawa-senyawa tersebut. Hasil karakterisasi SAA menunjukkan bahwa ketiga katalis heterogen termasuk ke dalam material mesopori. Radius pori yang diperoleh pada ketiga senyawa yaitu  Ni(acac)₂/ MC sebesar 3,288 nm, NiCl₂/ MC sebesar 4,799 nm, dan Ni(DBU)₂/ MC sebesar 4,763 nm. Uji daya adsorpsi dan uji reaksi karboksilasi fenilasetilena dengan CO₂ dengan katalis heterogen Ni(acac)₂/ MC, NiCl₂/ MC dan Ni(DBU)₂/ MC telah dilakukan dan membuktikan bahwa katalis Ni(acac)2/ MC memiliki daya adsorpsi lebih baik dan menghasilkan produk fenil maleat lebih banyak dibanding dengan katalis NiCl₂/ MC dan Ni(DBU)₂/ MC.

---

The continuous increase of CO₂ concentrations in the atmosphere for decades has influenced the global climate change. The development of renewable catalytic reactions is needed to transform CO₂ into more useful products. In this research, phenylacetylene carboxylation reaction with CO₂ was tested using catalysts Ni(acac)₂, NiCl₂ and Ni(DBU)₂ which were impregnated on the mesoporous carbon support. Mesoporous carbon materials, Ni(acac)₂ / MC, NiCl₂ / MC , and Ni(DBU)₂ / MC are characterized by FT-IR, XRD, SAA and SEM-EDS. Mesoporous carbon was successfully synthesized using soft template method which showed typical diffraction patterns of carbon materials which were 25.68^o and 43.26^o with the Miller index of (002) and (100), respectively. The impregnation process in Ni(acac)₂, NiCl₂ and Ni(DBU)₂ in mesoporous carbon support has been successfully proven by FT-IR analysis in which Ni(acac)₂ / MC, NiCl₂ / MC, and Ni(DBU)₂ / MC have similiar IR-spectrum to MC IR-spectrum because the compounds have been substituted into the pore so that no functional groups were detected in the samples. The results of the SAA characterization showed that the three heterogeneous catalysts belong to compounds that have meso-sized pores. The pore radius obtained in the three materials were 3,288 nm for Ni(acac)₂ / MC, 4,799 nm for NiCl₂ / MC, and 4,763 nm for Ni(DBU)₂ / MC. Adsorption test and phenylacetylene carboxylation reaction test with CO₂ with heterogeneous catalyst Ni(acac)₂ / MC, NiCl₂ / MC and Ni(DBU)₂ / MC have been carried out and proved the Ni(acac)₂ / MC catalyst had better adsorption performance and produced more phenyl maleate product compared to NiCl₂ / MC and Ni(DBU)₂ / MC catalysts."

"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."

"Pemanasan global merupakan peristiwa peningkatan gas rumah kaca (GRK) di atmosfer yang dapat menyebabkan perubahan iklim sehingga meningkatkan suhu permukaan bumi dan kenaikan permukaan laut. CO2 merupakan gas rumah kaca yang paling berlimpah di atmosfer yang menyebabkan efek rumah kaca. Salah satu upaya mitigasi CO2 adalah konversi CO2. Zeolit dengan struktur MFI merupakan katalis asam yang sering digunakan sebagai katalis pada reaksi konversi CO2 menjadi CH4. Salah satu zeolit dengan kerangka MFI adalah zeolit silicalite-1. Senyawa zeolit silicalite-1 merupakan kristal silikat bebas aluminium. Pada penelitian ini, dilakukan sintesis zeolit silicalite-1 mikropori dari material sintetik dan mineral alam dengan sumber kaolin bangka yang dimpregnasi menggunakan logam Ni dan bimetal NiZn. Karakterisasi dilakukan pada material awal dan terimpregnasi dengan XRD, FTIR, SEM-EDS, SAA-BET, dan XPS. Selanjutnya, Ni/silicalite-1 dan NiZn/silicalite-1 digunakan sebagai katalis pada konversi CO2 menjadi CH4. Reaksi dilakukan dengan memvariasikan massa katalis, waktu alir gas, suhu dan persen loading logam. Hasil karakterisasi menggunakan XRD menunjukkan puncak pada 8-10o dan 22-25o yang mengindikasikan terbentuknya kristal silicalite-1. Karakterisasi menggunakan SEM menunjukkan bentuk khas silicalite-1 yaitu coffin-like shaped yang terdapat pada semua jenis spesi katalis yang digunakan. Berdasarkan hasil XPS, senyawa Ni/silicalite-1 dan NiZn/silicalite-1 mengandung spesi Ni(0) dan NiO. Hasil uji aplikasi menunjukkan konversi dan %yield CH4 terbesar terdapat pada 20%-Ni/silicalite-1 sintetik yang masing-masing bernilai 60,08% dan 17,45%.Global warming is an increase of greenhouse gas in the atmosphere that can cause climate change, thereby increasing the surface temperature of the earth and rising sea levels. CO2 is one of the most abundant greenhouse gas in the atmosphere which causes the greenhouse effect. Currently, efforts to reduce CO2 are carried out in three ways, namely controlling CO2 gas emissions itself, storing CO2 gas and CO2 conversion. Zeolite with MFI structure is one catalyst that is often used as a catalyst in the conversion of CO2 to CH4. One of that zeolite with MFI framework is silicalite-1 zeolite. The silicalite-1 zeolite compound is an aluminum free silicate crystal. In this research, microporous silicalite-1 zeolite are synthesized from synthetic materials and natural minerals with the source of kaolin bangka impregnated with Ni metals and NiZn bimetallic. Characterization was performed on the initial material and the impregnated with XRD, FTIR, SEM-EDS, SAA-BET, and XPS. Furthermore, Ni/silicalite-1 and NiZn /silicalite-1 are used as catalysts in the conversion of CO2 to CH4. The reaction is carried out by varying the catalyst mass, gas flow time, temperature and metal loading percent. Catalysts with Ni metals are preferred because it has higher selectivity to CH4 , easy to obtain, and not expensive. The use of NiZn bimetal impregnation was carried out to determine the effect of transition metals on the conversion of CO2 to CH4. The highest conversion is shown by synthetic 20%-Ni/silicalite-1 with %conversion and %yield CH4 at 60,08% and 17,45%."

"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."

"Biogas adalah salah satu jenis energi alternatif yang memiliki potensi tinggi untuk mengurangi ketergantungan kebutuhan energi dunia terhadap bahan bakar fosil. Namun, kandungan CO₂ yang tinggi dalam biogas dapat menimbulkan masalah dalam penggunaannya. CO₂ dapat dipisahkan dari biogas melalui metode adsorpsi. Oleh karena itu, pada penelitian ini disintesis zeolit NaY dan Ni-MOF terkarbonisasi (Ni-MOFC) sebagai prekursor untuk sintesis suatu komposit zeolit NaY/Ni-MOFC. Dengan NaY yang dapat menyerap uap air dan Ni-MOFC yang memiliki afinitas tinggi terhadap CO₂, diharapkan bahwa material komposit dapat menjadi adsorben bagi CO₂, H2O, dan pengotor polar lainnya dalam satu tahap untuk digunakan dalam purifikasi biogas. Pada penelitian ini, setiap material dikarakterisasi dengan XRD, FTIR, BET, SEM-EDX, TGA, dan TEM. Dilakukan juga optimasi dengan RSM-BBD untuk digunakan untuk uji adsorpsi CO₂ dari model biogas oleh NaY/Ni-MOFC, yang kemudian diolah menjadi kapasitas adsorpsi dan selektivitas. Diperoleh kesimpulan bahwa kondisi optimal adsorpsi CO2 adalah adsorpsi yang dilakukan dengan NaY/Ni-MOFC dengan komposisi NaY:Ni MOFC = 5:1, suhu 25°C, dan %CO2 sebesar 40%. Dengan keadaan tersebut, diperoleh kapasitas adsorpsi CO2 sebesar 50,108 mmol/g dan selektivitas terhadap CO2 sebesar 4,925.

---

Biogas is an up and coming class of alternative energy that has high potential to redunce the dependence of the world’s energy needs on fossil fuels. However, the high CO₂ content in biogas can cause problems when biogas is used as an energy source. CO₂ can be separated from biogas through adsorption. Therefore, in this study, NaY zeolite and carbonized Ni-MOF (Ni-MOFC) will be synthesized as precursors for the synthesis of a NaY/Ni-MOFC composite material. With NaY’s ability for water vapor adsorption and Ni-MOFC’s high affinity for CO₂ among other things, it is predicted that the resulting composite material will be able to adsorb CO₂, H2O, and other polar impurities within one stage to be used in biogas purification. In this study, every material is characterized by XRD, FTIR, BET, SEM-EDX, TGA, and TEM. Optimization with RSM-BBD is also conducted to be used as a basis for the CO₂ adsorption test, from which was calculated adsorption capacity and selectivity. It is concluded that the optimal condition of CO2 adsorption was adsorption conducted with NaY/Ni-MOFC with NaY:Ni-MOFC composition of 5:1, temperature of 25°C, and %CO2 of 40%. Under these conditions, the CO2 adsorption capacity of 50.108 mmol/g and selectivity to CO2 of 4.925 were obtained."

"Konversi karbon dioksida CO2 menjadi senyawa lain menjadi sangat menguntungkan karena jumlahnya di atmosfer yang melimpah, namun karbon dioksida CO2 memiliki termodinamik dan kinetik yang stabil sehingga diperlukan bantuan logam bervalensi rendah contohnya Ni 0 untuk dapat bereaksi. Pada penelitian ini digunakan ZSM-5 terimpregnasi logam nikel sebagai katalis reaksi karboksilasi asetilena dengan karbon dioksida menjadi asam akrilat. Hasil karakterisasi XRD menunjukan bahwa material ZSM-5 memiliki kristalinitas yang tinggi berhasil disintesis. Analisa menggunakan SEM menunjukan bahwa ZSM-5 memiliki morfologi bentuk coffin-like dan setelah diimpregnasi tidak mempengaruhi struktur morfologi kristal. Karakterisasi menggunakan BET ZSM-5 hirarki yang disintesis memiliki pori berukuran meso karena terbentuk hystheresis loop. Analisa menggunakan AAS menghasilkan loading logam nikel pada ZSM-5 mikropori sebesar 1,9 sedangkan ZSM-5 hirarki sebesar 2,1. Karakterisasi XPS menunjukan logam nikel pada ZSM-5 memiliki biloks nol 0. Pada reaksi karboksilasi asetilena dengan karbon dioksida dengan target produk asam akrilat, analisis HPLC tidak menunjukan adanya asam akrilat dalam reaksi. Namun, terdapat puncak lain pada waktu retensi 3,625 dimana pada material ZSM-5 hirarki didapatkan kondisi optimum pada suhu 80oC dengan suhu 12 jam dan menggunakan katalis Ni 0 /ZSM-5 mikropori didapatkan kondisi optimum pada suhu 40oC dan waktu 12 jam.

---

Conversion of carbon dioxide CO2 into other compounds become very advantageous because of the abundance in the atmosphere, but carbon dioxide CO2 has thermodynamic and kinetic stable so it need low valent metal for example Ni 0 to react. In this studym ZSM 5 impregnated with nickel metal as catalyst of carboxylation reaction of acetylene with carbon dioxide to acrylic acid. XRD characterization results ZSM 5 material has high crytalinity successfully synthesized. Analysis using SEM obtain ZSM 5 has coffin like morphology and after impregnation doesnt affect the crystal morphology structure. Characterization using BET proves that ZSM 5 hierarchy has meso sized pore because of the hysthereses loop. Analyzing using AAS obtained that load of nickel metal on ZSM 5 micropore equal to 1,9 meanwhile ZSM 5 hierarchy equal to 2,1. The characterization of XPS show nickel metal on ZSM 5 has zero 0 oxidation. Carboxylation reaction of acetylene with carbon dioxide targeted acrylic acid product, HPLC analysis doesnt show the presence of acrylic acid in the reaction. However, there was another peak at retention time of 3,625 where in herarchical ZSM 5 material the optimum condition was obtained at temperature 80oC with 12 hours while using Ni 0 ZSM 5 micropore catalyst obtained 80oC with 12 hours. "

"Karbon dioksida merupakan salah satu gas utama yang menyebabkan emisi gas rumah kaca yang berada pada atmosfer. Dikarenakan sifatnya yang inert, CO2 sulit bereaksi dengan senyawa lain sehingga dibutuhkan suatu katalis. Pada penelitian ini digunakan zeolit ZSM-5 berpori hirarki bersumber mineral alam yaitu zeolit alam Bayat dan kaolin Bangka yang diimpregnasi bimetal NiZn sebagai katalis untuk mengkonversi CO2 dengan bantuan dari asetilena untuk menghasilkan asam akrilat. Zeolit ZSM-5 alam berpori hirarki disintesis menggunakan metode double template, dengan primary template TPAOH sebagai pengarah framework MFI serta secondary template PDDA-M sebagai pengarah struktur mesopori. Impregnasi logam bimetal nikel (Ni) dan seng (Zn) dengan metode co-impregnation lalu direduksi dengan aliran gas H2. Karakterisasi material ZSM-5 alam berpori hirarki dan NiZn/ZSM-5 alam berpori hirarki dilakukan dengan menggunakan FTIR, XRD, XRF, dan SEM-EDS. Analisis XRD menunjukkan kristalinitas dari ZSM-5 alam berpori hirarki berhasil disintesis. Analisis FTIR menunjukkan telah terjadinya dekomposisi template melalui kalsinasi. Pencitraan SEM menunjukkan morfologi material dengan bentuk coffin like-shaped yang merupakan ciri khas ZSM-5. Hasil analisisis EDS menunjukkan persen loading Ni dan Zn dalam ZSM-5 masing-masing sebesar 6,38% dan 3,23%. Reaksi karboksilasi asetilena dengan CO2 dilakukan dalam reaktor batch dengan variasi tekanan yaitu 1,5 bar, 2,5 bar, dan 3,5 bar. Produk hasil reaksi yang terbentuk dianalisis dengan HPLC. Dari hasil analisis HPLC diperoleh puncak pada waktu retensi 3,45 menit dengan kondisi optimum yaitu tekanan 2,5 bar, dan luas area sebesar 302,836 mAU. Sehingga, menunjukkan tidak adanya asam akrilat dalam produk.

---

Carbon dioxide is one of the main gases that cause greenhouse gas emissions in the atmosphere. Because of its inert in the atmosphere, the catalyst is needed to help CO2 react with other compounds. In this research, hierarchical ZSM-5 was prepared from natural minerals as sources, which is natural zeolite Bayat and Bangka kaolin then impregnated with bimetallic Ni-Zn as a catalyst to convert CO2 with support of acetylene to produce acrylic acid. Hierarchical zeolite ZSM-5 was synthesized using double template method, with TPAOH as its primary template that directed to MFI framework and PDDA-M as its secondary template that directed mesoporous structure. Impregnation of nickel (Ni) and zinc (Zn) bimetallic was conducted by co-impregnation method followed by reduction H2 gas flow. Material characterization of natural ZSM-5 hierarchy and NiZn/ZSM-5 hierarchy were conducted FTIR, XRD, XRF, and SEM-EDS. FTIR analysis shows that there has been a decomposition of templates through calcination. XRD analysis showed that the crystallinity of the ZSM-5 hierarchy was synthesized successfully. SEM analysis shows the morphology of the material with the coffin like-shaped which is characteristic of the ZSM-5. The EDS analysis shows percent loading of Ni and Zn in ZSM-5 are 6.38% and 3.23%. The acetylene carboxylation reaction with CO2 was carried out in a batch reactor with pressure variations 1.5 bar, 2.5 bar, and 3.5 bar. The products formed were analyzed by HPLC and GCMS. HPLC analysis shows a new peak at a retention time of 3,625 minutes. The optimum condition was obtained at 2.5 bar and the value is 302.836 mAU. So, it shows do not contain acrylic acid in the product."

"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.

---

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."

"Simpanan karbon di atas permukaan tanah (BAP) merupakan sumber terbesar cadangan karbon sekaligus sumber yang paling berisiko mengalami penurunan karena degradasi lahan. Hutan Kota Universitas Indonesia (UI) merupakan salah satu kawasan yang berperan penting dalam menyerap dan menyimpan karbon, terutama karbon dari polutan di sekitarnya. Penghitungan cadangan karbon BAP Hutan Kota UI telah dilakukan dengan membagi lokasi penelitian menjadi 3, yaitu Zona Vegetasi Alami, Zona Wallace Barat, dan Zona Wallace Timur. Penelitian dilakukan dengan metode destruktif untuk tumbuhan bawah dan metode non destruktif (menggunakan persamaan alometrik) untuk vegetasi tingkat pohon, tiang, dan pancang.Hasil penghitungan menunjukkan bahwa potensi cadangan karbon untuk Zona Vegetasi Alami, Zona Wallace Barat, dan Zona Wallace Timur berturut-turut adalah 164,308 ton/ha, 103,527 ton/ha, dan 119,165 ton/ha. Cadangan karbon paling banyak berasal pada pohon Acacia mangium (Willd.). Acacia mangium juga merupakan jenis dengan nilai kepentingan (NK) tertinggi. Secara keseluruhan, potensi simpanan karbon di Hutan Kota UI adalah 9.465,866 ton, sedangkan potensi serapan atau emisinya CO2-nya sebesar 34.711,3325 ton.

---

Carbon storage on the above ground biomass (AGB) is the largest source of carbon stocks. But it is also a source of carbon that are most vulnerable to land degradation. Urban Forest in Universitas Indonesia (UI) is one area that plays an important role in absorbing and storing carbon, especially carbon from pollutant in the vicinity. Calculation of carbon stock in UI?s urban forest has been done by dividing into three study sites, the Natural Vegetation Zone, West Wallace Zone, and East Wallace Zone. The study was conducted by using destructive methods for undergrowth and non destructive method (using allometric equations) for the vegetation of trees, poles, and stakes.The results show that the potential carbon reserve for Natural Vegetation Zone is 164,308 tons/ha, West Wallace Zone is 103,527 tons/ha, and East Wallace Zone is 119,165 tons/ha. Carbon stocks mostly came from the Acacia mangium and it is also a species with the highest importance value index. Overall, the potential for carbon storage in UI?s urban forest is 9.465,866 tons, while the potential emission of CO2 is equal to 34.711,3325 tons."