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Abstrak :
Sintesis TiO2 mesopori telah dilakukan dengan metode hidrotermal pada suhu 120 0C selama 18 jam, dengan titanium tetraisopropoksida (TTIP) digunakan sebagai prekursor dan polietilen glikol (PEG) sebagai template. Hasil sintesis dikalsinasi pada suhu 550 0C selama 8 jam untuk menghilangkan template. Hasil sintesis dikarakterisasi dengan XRD, SEM, BET, FTIR, dan UV-DRS. Hasil karakterisasi XRD dan UV-DRS menunjukkan bahwa TiO2 hasil sintesis merupakan kristal bertipe anatase dengan sedikit rutil sebagai pengotor, dengan nilai energi celah sebesar 3,13 eV. Hasil karakterisasi BET menunjukkan pola isoterm adsorpsi mesopori dengan hysteris loop, dengan diameter rata- rata pori sebesar 7,23 nm dan luas permukaan sebesar 35,56 m2/g. Hasil sintesis diuji aktivitas fotokatakatalitiknya terhadap degradasi formaldehida. Degradasi fotokatalitik dilakukan dalam reaktor yang dilengkapi dengan lampu UV dan tabung yang telah dilapisi TiO2 hasil sintesis. Hasil degradasi formaldehida secara fotokatalitik menunjukkan penurunan konsentrasi formaldehida hingga 26 % pada menit ke-40. Hasil ini lebih baik dibandingkan proses fotokatalisis, dengan konsetrasi sisa formaldehida sebesar 49 %. ......Mesoporous TiO2 has been synthesized using hydrothermal method at 120 0C for 18 hours, with titanium tetraisopropoxide (TTIP) as precursor and polyethylene glycol (PEG) as template. The sample was calcined at 550 0C for 8 hours to remove the template. The as-synthesized sample was characterized by XRD, SEM, BET surface area, FTIR, and UV-DRS. Characterization by XRD and UV-DRS showed anatase and slightly rutile phase, as impurities, for crystal structure with band gap energy 3,13 eV, respectively the result of BET surface area showed hysteresis loop in its adsorption isotherm curve. The surface area of sample was 35,56 m2/g, with average pore diameter about 7,23 nm. The photocatalytic activity of sample was studied by photodegradation of formaldehyde in gas phase, using batch reactor employed with as-synthesized TiO2 coated glass tube as reaction vessel. The result of photocatalytic process showed degradation of formaldehyde concentration up to 26 % after 40 minute reaction. This result is better than that obtained in photolysis process, with residual concentration of formaldehyde about 49 %.

Abstrak :
ABSTRAK Karbon mesopori merupakan material yang menjanjikan dan sering digunakan sebagai elektroda pada Electric Double-layer (EDL) supercapacitor karena memiliki luas permukaan dan volume pori yang baik serta memiliki pori mesopori yang banyak. Pada penelitian ini, dilakukan sintesis karbon mesopori yang berstruktur berkerut yang termodifikasi dengan boron dan nitrogen yang mana diharapkan dapat meningkatkan performa penyimpanan energy pada EDL supercapacitor. Sintesis mesopori karbon dilakukan dengan menggunakan mesopori silika berkerut sebagai hard template dan glukosa sebagai sumber karbon. Modifikasi dengan doping atom boron dan nitrogen, dengan menggunakan asam borat sebagai sumber boron dan urea sebagai sumber nitrogen, dapat meningkatkan performa dari supercapacitor. Mesopori karbon yang telah disintesis dikarakterisasi dengan menggunakan SEM, TEM, BET surface analyzer, XRD dan Raman spektrofotometer, dan untuk pengukuran kapasitas spesifik digunakan metode cyclic voltammetry (CV) pada scan rate 100-400 mV/s dan galvanostatic charge-discharge. Kapasitas spesifik yang paling besar dimiliki B-Mesopori karbon sebesar 173,68 F/g pada metode cyclic voltammtery dan Mesopori karbon sebesar 5,489 F/g pada metode galvanostatic charge-discharge. Namun, modifikasi dengan co-doping boron dan nitrogen menurunkan kapasitas spesifik yang dihasilkan karena terbentuknya ikatan B-N yang membuat ion pada elektrolit sukar teradsorpsi pada permukaan karbon.

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ABSTRACT Mesoporous carbon is a promising material which can be used as an electrode in Electric Double-layer (EDL) supercapacitors because it has a good surface area and pore volume and has many mesoporous pores. In this study, modified carbon mesoporous synthesis was carried out with boron and nitrogen which is expected to improve energy storage performance in EDL supercapacitors. Heteroatom doping modification with boron and nitrogen could increase specific capacitance of supercapacitor. B-Mesoporous carbon has highest specific capacitance was approximately 173,68 F/g. However, B,N co-dopedmesoporous carbon has smallest specific capacitance because B-N bond formed that caused ion in electrolyte difficult to absorbed on the surface of carbon material.

Abstrak :
Reaksi degradasi selulosa menggunakan metode Fenton dan mirip-Fenton dengan katalis Mn/ZSM-5 dan Fe/ZSM-5 dalam media asam fosfat telah diteliti. Mn/ZSM-5 (Mn 2 wt% dan Fe/ZSM-5 (Fe 2 wt%) telah berhasil disintesis dengan metode impregnasi menggunakan MnCl2.4H2O dan (NH4)2FeSO4.6H2O. Hasil karakterisasi menggunakan XRD, FTIR, SEM, dan BET menunjukkan zeolit yang terbentuk merupakan ZSM-5 mesopori. Katalis yang telah disintesis digunakan untuk mendegradasi selulosa dan mengkonversinya menjadi asam levulinat. Larutan asam fosfat dipilih sebagai media reaktif untuk degradasi selulosa karena memiliki kemampuan yang baik untuk memutuskan ikatan hidrogen inter- dan intramolekular pada selulosa. Sistem mirip Fenton yang terdiri dari H2O2 dan Mn/ZSM-5 dapat digunakan untuk degradasi selulosa dan menghasilkan asam levulinat. Reaksi degradasi dilakukan pada suhu 100 °C menggunakan tiga jenis katalis, yaitu ZSM-5, Mn/ZSM-5 2 wt%, dan Fe/ZSM-5 2 wt% dan dilakukan pengukuran pada sampel hasil reaksi 0 jam, 2 jam, 4 jam, 6 jam, dan 8 jam. Ketiga reaksi mengalami perubahan menjadi charcoal pada waktu 2 jam sehingga reaksi tidak dijalankan sampai selesai. Dari pengukuran sampel hasil reaksi 0 jam, didapatkan konsentrasi asam levulinat paling tinggi dengan menggunakan katalis Mn/ZSM-5 yaitu sebesar 253,1204 ppm. Sedangkan pada reaksi dengan Fe/ZSM-5 didapat konsentrasi asam levulinat sebesar 218,7217 ppm dan dengan ZSM-5 konsentrasinya 228,6223 ppm.

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Degradation of cellulose to produce levulinic acid with Fenton and like-Fenton methods using Mn/ZSM-5 and Fe/ZSM-5 catalysts has been investigated. Mn/ZSM-5 (Mn 2 wt%) and Fe/ZSM-5 (2 wt%) have been successfully synthesized through impregnation methods using MnCl2.4H2O dan (NH4)2FeSO4.6H2O respectively. Results of characterization using XRD, FTIR, BET, and SEM showed that the ZSM-5 formed a mesopore. Catalyst has been synthesized which has been used to degradated cellulose and conversed into levulinic acid. Phosphoric acid solution was selected as the reactive medium for the degradation of cellulose due to its good ability to destroy inter- and intra-molecular hydrogen bond so as to promote cellulose activation. Fenton-like system consisting of H2O2 and Mn/ZSM-5 can be used effectively for the degradation of cellulose and produce levulinic acid. The reaction was conducted at 100° C using three types of catalyst, the ZSM-5, Mn/ZSM-5 with 2 wt%, and 2 wt% Fe/ZSM-5 and the measurement of the sample onto result of reaction within 0 hour, 2 hours, 4 hours, 6 hours, and 8 hours. All the reaction have changed into charcoal within 2 hours so the reaction cannot be completed. From measurement of sample reaction within 0 hour, we got the levuinic acid concentrate which is the highest using Mn/ZSM-5 catalyst such as 253,1204 ppm. In reaction with Fe/ZSM-5 catalyst, we got the levuinic acid concentrate such as 218,7217 ppm and with ZSM-5 catalyst, the concerntrate was 228,6223 ppm.

Abstrak :
Karbon mesopori telah berhasil disintesis melalui metode soft template dengan Pluronic F-127 sebagai agen pembentuk pori; phloroglucinol dan formaldehida sebagai sumber karbon. Material ini dimodifikasi lebih lanjut dengan etilendiamin (EDA) dan trietilentetramin (TETA). Struktur dan sifat dari karbon mesopori termodifikasi dikarakterisasi dengan FTIR, Analisis Luas Permukaan, EDS, XRD, dan FE-SEM. Spektra FTIR dari karbon mesopori termodifikasi gugus amina memiliki puncak serapan 3100~3600 cm-1, 1485~1579 cm-1, dan 2924 cm-1 yang merupakan karakter dari senyawa amina. Analisis unsur menunjukkan karbon mesopori termodifikasi 50% EDA dan karbon mesopori termodifikasi 50% TETA memiliki kandungan nitrogen masing-masing 23,23% dan 20,24%. Analisis luas permukaan pada karbon mesopori termodifikasi memperlihatkan berkurangnya luas permukaan, volume pori, dan diameter pori namun masih mempertahankan sifat mesoporinya. Hasil ini menunjukkan karbon mesopori telah berhasil dimodifikasi dengan gugus amina. Karbon mesopori termodifikasi gugus amina telah diuji sebagai adsorben CO 2 dan hasilnya dibandingkan dengan karbon mesopori tanpa modifikasi. Kadar CO 2 sebelum dan sesudah melewati adsorben dihitung dengan metode titrasi. Hasil eksperimen menunjukkan gugus amina telah berhasil meningkatkan kemampuan adsorpsi dari karbon mesopori.

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Mesoporous carbon has been successfully synthesized by soft templating method with Pluronic F-127 for generation of porous carbon structures; phloroglucinol and formaldehyde as carbon source. Furthermore, the mesoporous carbon was modified with ethylenediamine (EDA) and triethylenetetramine (TETA). The structure and properties of the modified mesoporous carbon were characterized by using XRD, FTIR, Surface Area Analysis, EDS, XRD, and FE-SEM. The FTIR spectra of amine-modified mesoporous carbon have peaks at 3100~3600 cm-1, 1485~1579 cm-1, and 2924 cm-1 which is characteristic of amine compounds. Elemental analysis showed that the 50% EDA-modified mesoporous carbon and 50% TETA-modified mesoporous carbon has 23.23% and 20.24% nitrogen content, respectively. Surface area analysis of this material showed surface area, pore volume, and pore diameter have decreased but still maintained mesoporous character. These results indicated mesoporous carbon has been successfully modified with amine groups. The amine-modified mesoporous carbon has been tested as CO 2 adsorbent and compared to the parent mesoporous carbon. The amount of CO 2 before and after adsorption were measured with titration method. The result showed that amine groups have successfully improved the CO 2 adsorption of mesoporous carbon.

Abstrak :
The SBA-l5 material can be applied on many industries such as catalyst, adsorbent and membrane material. Pore size in SBA-I5 can be categorized in mesoporous material, because the size ranges from 2- 50 nm. Pore diameter generally can be observed by Scanning Electron Microscope (SEM) or Transmission Electron Microscope (TEM). Another method to determine the pore diameter is using a Atomic Force Microscope (AFA/D. The topography observation from AFM can identify the size and pore shape of SBA-I 5 in nanometer order: The result of AFM showed that the pore size ofSBA-i5 is 3.27 nm.

Abstrak :
Sistem pori hierarki pada zeolit yang dikembangkan untuk mengatasi keterbatasan zeolit konvensional dapat diperoleh dengan penambahan pori dan dapat menghasilkan dua bentuk konfigurasi mesopori, yaitu mesopori intra dan interkristalin. Mesopori intrakristalin merupakan pori berukuran meso yang terletak pada kristal zeolit, sedangkan mesopori interkristalin merupakan pori berukuran meso yang terbentuk sebagai celah di antara nanozeolit yang masing-masing disintesis menggunakan metode templating dan mesoporogen-free. Penelitian ini dilakukan untuk menganalisa pengaruh konfigurasi mesopori terhadap sifat fisika-kimia dari ZSM-5 hierarki dan pengaruhnya terhadap kobalt oksida yang dimodifikasikan secara impregnasi. Analisa sifat fisika-kimia ZSM-5 termodifikasi oksida kobalt dilakukan berdasarkan karakterisasi XRD, FTIR, XRF, N2 physisorption, SEM, TEM, H2-TPR, dan XPS. Kemudian reaksi oksidasi parsial metana diujikan sebagai reaksi model untuk menganalisa pengaruh konfigurasi mesopori terhadap aktivitas katalisis ZSM-5 hierarki termodifikasi oksida kobalt. Uji katalisis oksida metana dengan variasi waktu menghasilkan produk teroksidasi berupa metanol, formaldehida, asam format, dan karbon dioksida. Hasil uji katalisis menunjukkan bahwa konfigurasi mesopori interkristalin cenderung mengoksidasi reaksi lebih kuat yang dikonfirmasi bahwa pada waktu tersingkat, yaitu 30 menit, dihasilkan formaldehida sebagai produk utama yang merupakan hasil oksidasi lanjutan dari senyawa metanol. ......Zeolite hierarchical porous system that was developed to overcome the limitations of conventional zeolite could be achieved though the introduction of secondary porous system and could lead to the creation of two types of mesoporous configuration: intra- and inter-crystalline mesopore. Intracrystalline mesoporous presented within zeolite crystals white inter-crystalline mesoporous presented as voids between zeolite crystals where both were synthesized through templating and mesoporogen-free method, respectively. In this study, the influence of mesoporous configuration to the physicochemical properties of hierarchical ZSM-5 are analysed, including the influence on the creation of cobalt oxide modified via impregnation method. Analysis of physicochemical properties were determined by characterization using XRD, FTIR, XRF, N2 physisorption, SEM, TEM, H2-TPR, and XPS. Analysis on the catalytic activity were carried out using methane partial oxidation reaction as model reaction. Methane oxidation reaction with variation of reaction time showed various type of oxygenated products, including of methanol, formaldehyde, formic acid, and small trace of carbon dioxide. Catalytic results suggested that catalysts with inter-crystalline mesoporous configuration oxidize reaction stronger compared to intracrystalline type. These results confirmed by the formation of formaldehyde as the oxygenated form of methanol as major product in the brief reaction time of 30 mins.

Abstrak :
[ABSTRAK
Indonesia memiliki banyak sumber daya alam ilmenit yang dapat dimanfaatkan lebih lanjut menjadi material mesopori Fe2O3 TiO2. Material mesopori dengan dinding (wall) yang tersusun atas nano-kristalin TiO2 adalah kandidat yang sangat menjanjikan dalam memberikan sumbangan yang sangat signifikan untuk mengatasi permasalahan lingkungan dan krisis energi yang melanda dunia. Namun demikian, hingga sekarang ini masih sulit untuk memperoleh kombinasi sinergis dua hal utama yaitu susunan pori yang teratur (highly-oriented) dan tingkat kristalinitas yang tinggi. Penelitian ini bertujuan untuk mensintesis mesopori Fe2O3 TiO2 dari mineral ilmenit (FeTiO3) untuk aplikasi pemurnian air limbah dan pembuatan prototipe DSSC. Metode yang digunakan dalam penelitian adalah kombinasi teknik hidrotermal dan sol−gel. Tahapan proses adalah mineral ilmenit yang telah dihaluskan dilakukan proses dekomposisi dengan larutan basa dalam autoklaf kemudian dilanjutkan dengan proses pelindian menggunakan asam sulfat. Larutan TiOSO4 yang dihasilkan digunakan sebagai prekursor dalam mempersiapkan nanopartikel TiO2 atau material mesopori Fe2O3 TiO2. Pengontrolan dalam proses sol−gel dilakukan dengan penambahan Fe, dextrin dan triblock copolimer. Hasil penelitian dikarakterisasi menggunakan XRF, AAS, TEM/SEM, BET, XRD, DRS, UV Vis. Hasil penelitian memberikan gambaran tentang potensi yang besar terhadap ilmenit Bangka untuk dimanfaatkan sebagai bahan baku dalam pembuatan material mesopori Fe2O3 TiO2. Ilmenit terdekomposisi dengan pelarut basa (KOH dan NaOH) membentuk fase intermediet yaitu kalium titanat dan natrium titanat dengan morfologi yang berbentuk benang-benang halus. Penambahan bubuk Fe dan dextrin mampu mengontrol pembentukan nanopartikel dan meningkatkan kemurnian TiO2. Penelitian ini juga berhasil mempersiapkan mesopori Fe2O3 TiO2 yang digolongkan sebagai bidang kristal anatase maupun rutil dengan ukuran kristal rata-rata berkisar 5 -7 nm, energi band gab berkisar 3,00 ? 3,16 eV dan luas permukaan, SBET berkisar.100 ? 151 m2/g.;

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ABSTRACT
Indonesia has many natural resources including ilmenite which could be exploited further into mesoporous TiO2 Fe2O3 materials. Mesoporous materials with walls composed of nano-crystalline TiO2 are very promising candidate in a very significant contribution for solving environmental problems and energy crisis that hit in the world. However, until now it is still difficult to obtain a synergistic combination of two major things that the regular arrangement of pores (highlyoriented) and a high degree of crystallinity. This study aims to synthesize mesoporous TiO2 Fe2O3 of the ilmenite (FeTiO3) mineral for waste water purification applications and prototyping DSSC. The method used in the study is a combination of hydrothermal and sol-gel techniques. Stage of the process was ilmenite mineral which has been smoothed carried out the decomposition process using alkaline solution in the autoclave and then followed by a leaching process using sulfuric acid. The TiOSO4 solution obtained was used as a precursor in the preparation of TiO2 nanoparticles or mesoporous TiO2 Fe2O3 material. Controlling the sol-gel process was done with the addition of Fe, dextrin and triblock copolimer. The results of the study were characterized using XRF, AAS, TEM/SEM, BET, XRD, DRS, UV-Vis apparatus. The results of the study provided an overview of the enormous potential of the Bangka-Indonesia ilmenite to be used as raw material in the manufacture of mesoporous TiO2 Fe2O3 materials. Ilmenite decomposed by alkaline solvent (KOH and NaOH) formed the intermediate phase of potassium titanate and sodium titanate with morphology shaped by fine threads. The addition of Fe powder and dextrin were able to control the formation nanoparticles and increase the purity of TiO2. This study also succeeded in preparing mesoporous TiO2 Fe2O3 classified as anatase and rutile crystal planes with an average crystal size ranges from 5 to 7 nm, the band gap energy ranges from 3.00 to 3.16 eV and the surface area (SBET) ranges from 100 to 151 m2/g.;Indonesia has many natural resources including ilmenite which could be exploited further into mesoporous TiO2 Fe2O3 materials. Mesoporous materials with walls composed of nano-crystalline TiO2 are very promising candidate in a very significant contribution for solving environmental problems and energy crisis that hit in the world. However, until now it is still difficult to obtain a synergistic combination of two major things that the regular arrangement of pores (highlyoriented) and a high degree of crystallinity. This study aims to synthesize mesoporous TiO2 Fe2O3 of the ilmenite (FeTiO3) mineral for waste water purification applications and prototyping DSSC. The method used in the study is a combination of hydrothermal and sol-gel techniques. Stage of the process was ilmenite mineral which has been smoothed carried out the decomposition process using alkaline solution in the autoclave and then followed by a leaching process using sulfuric acid. The TiOSO4 solution obtained was used as a precursor in the preparation of TiO2 nanoparticles or mesoporous TiO2 Fe2O3 material. Controlling the sol-gel process was done with the addition of Fe, dextrin and triblock copolimer. The results of the study were characterized using XRF, AAS, TEM/SEM, BET, XRD, DRS, UV-Vis apparatus. The results of the study provided an overview of the enormous potential of the Bangka-Indonesia ilmenite to be used as raw material in the manufacture of mesoporous TiO2 Fe2O3 materials. Ilmenite decomposed by alkaline solvent (KOH and NaOH) formed the intermediate phase of potassium titanate and sodium titanate with morphology shaped by fine threads. The addition of Fe powder and dextrin were able to control the formation nanoparticles and increase the purity of TiO2. This study also succeeded in preparing mesoporous TiO2 Fe2O3 classified as anatase and rutile crystal planes with an average crystal size ranges from 5 to 7 nm, the band gap energy ranges from 3.00 to 3.16 eV and the surface area (SBET) ranges from 100 to 151 m2/g.;Indonesia has many natural resources including ilmenite which could be exploited further into mesoporous TiO2 Fe2O3 materials. Mesoporous materials with walls composed of nano-crystalline TiO2 are very promising candidate in a very significant contribution for solving environmental problems and energy crisis that hit in the world. However, until now it is still difficult to obtain a synergistic combination of two major things that the regular arrangement of pores (highlyoriented) and a high degree of crystallinity. This study aims to synthesize mesoporous TiO2 Fe2O3 of the ilmenite (FeTiO3) mineral for waste water purification applications and prototyping DSSC. The method used in the study is a combination of hydrothermal and sol-gel techniques. Stage of the process was ilmenite mineral which has been smoothed carried out the decomposition process using alkaline solution in the autoclave and then followed by a leaching process using sulfuric acid. The TiOSO4 solution obtained was used as a precursor in the preparation of TiO2 nanoparticles or mesoporous TiO2 Fe2O3 material. Controlling the sol-gel process was done with the addition of Fe, dextrin and triblock copolimer. The results of the study were characterized using XRF, AAS, TEM/SEM, BET, XRD, DRS, UV-Vis apparatus. The results of the study provided an overview of the enormous potential of the Bangka-Indonesia ilmenite to be used as raw material in the manufacture of mesoporous TiO2 Fe2O3 materials. Ilmenite decomposed by alkaline solvent (KOH and NaOH) formed the intermediate phase of potassium titanate and sodium titanate with morphology shaped by fine threads. The addition of Fe powder and dextrin were able to control the formation nanoparticles and increase the purity of TiO2. This study also succeeded in preparing mesoporous TiO2 Fe2O3 classified as anatase and rutile crystal planes with an average crystal size ranges from 5 to 7 nm, the band gap energy ranges from 3.00 to 3.16 eV and the surface area (SBET) ranges from 100 to 151 m2/g., Indonesia has many natural resources including ilmenite which could be exploited further into mesoporous TiO2 Fe2O3 materials. Mesoporous materials with walls composed of nano-crystalline TiO2 are very promising candidate in a very significant contribution for solving environmental problems and energy crisis that hit in the world. However, until now it is still difficult to obtain a synergistic combination of two major things that the regular arrangement of pores (highlyoriented) and a high degree of crystallinity. This study aims to synthesize mesoporous TiO2 Fe2O3 of the ilmenite (FeTiO3) mineral for waste water purification applications and prototyping DSSC. The method used in the study is a combination of hydrothermal and sol-gel techniques. Stage of the process was ilmenite mineral which has been smoothed carried out the decomposition process using alkaline solution in the autoclave and then followed by a leaching process using sulfuric acid. The TiOSO4 solution obtained was used as a precursor in the preparation of TiO2 nanoparticles or mesoporous TiO2 Fe2O3 material. Controlling the sol-gel process was done with the addition of Fe, dextrin and triblock copolimer. The results of the study were characterized using XRF, AAS, TEM/SEM, BET, XRD, DRS, UV-Vis apparatus. The results of the study provided an overview of the enormous potential of the Bangka-Indonesia ilmenite to be used as raw material in the manufacture of mesoporous TiO2 Fe2O3 materials. Ilmenite decomposed by alkaline solvent (KOH and NaOH) formed the intermediate phase of potassium titanate and sodium titanate with morphology shaped by fine threads. The addition of Fe powder and dextrin were able to control the formation nanoparticles and increase the purity of TiO2. This study also succeeded in preparing mesoporous TiO2 Fe2O3 classified as anatase and rutile crystal planes with an average crystal size ranges from 5 to 7 nm, the band gap energy ranges from 3.00 to 3.16 eV and the surface area (SBET) ranges from 100 to 151 m2/g.]

Abstrak :
Zeolit terstruktur yang menggabungkan mikro- dan mesoporositas disiapkan dengan menggunakan metode desilikasi dalam larutan basa NaOH 0,2 M terhadap dua jenis zeolit ZSM5: ZSM5 komersial tanpa template ? (Si/Al 8,62) dan ZSM5 yang disintesis menggunakan template (Si/Al 25). Pola difraksi sinar-X menunjukkan bahwa kristalinitas dan short-range order dalam zeolit yang didesilikasi menggunakan basa tidak mengalami perubahan dibandingkan dengan zeolit awal untuk kedua sampel. Pengukuran permukaan pada zeolit ZSM5 ?tanpa template? menunjukkan bahwa luas permukaan berkurang sebesar 2,33% namun isoterm adsorpsinya dapat dikategorikan ke dalam Tipe IV, yang merupakan karakteristik dari material mesopori. Hal ini didukung dari adanya perubahan pada volume mesopori dari 0,38 cm 3/g menjadi 0,45 cm 3/g, dan distribusi ukuran pori BJH meningkat dari 10 menjadi 18 nm. Di sisi lain, luas permukaan ZSM5 sintesis yang didesilikasi dengan basa meningkat sebesar 8,25%, tetapi kurva isoterm adsorpsinya menjadi Tipe I yang terkait dengan struktur mikropori. Lebih jauh lagi, analisis t-plot menunjukkan bahwa volume mesopori dari ZSM5 sintesis yang didesilikasi dengan basa meningkat sebesar 26%, dari 0,037 cm 3/g menjadi 0,046 cm 3/g, dengan sifat intrinsik zeolit tidak berubah. Dari penelitian ini, dapat disimpulkan bahwa keberadaan template organik memainkan peranan penting dalam mempertahankan struktur zeolit selama perlakuan menggunakan basa.

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Abstract
Hierarchical zeolites combining micro- and mesoporosity were prepared using desilication method in alkaline solution of NaOH 0.2 M on two types of ZSM5: ?template free? commercial ZSM5 (Si/Al 8.62) and ?templated? as-synthesized ZSM5 (Si/Al 25). The powder X-ray diffraction patterns revealed that crystallinity and short-range order in the alkaline treated zeolites were virtually unchanged compared to both of the parent zeolites. The surface measurement on the template free ZSM5 zeolites showed that the surface area was reduced by 2.33%, but the adsorption isotherm can be categorized into Type IV which is typical of for mesoporous material, supported by the change in mesopore volume, and the BJH pore size distribution (from 10 to 18 nm). On the other hand, the surface area of the alkaline treated as-synthesized ZSM5 was increased by 8.25%, but its isotherm adsorption curve falls into Type I for microporous structure. The mesopore volume was increased by 26%, from 0.037 cm 3/g to 0.046 cm 3/g, with the intrinsic zeolite properties were mainly preserved. Based on these results, it can be concluded that the existence of organic template plays an important role in preserving the zeolitic structure during the alkaline treatment.

Abstrak :
Pemanfaatan bahan bakar fosil, batu bara, minyak, serta gas alam yang kaya akan karbon semakin marak digunakan guna keberlangsungan hidup manusia. Pemanfaatan bahan-bahan tersebut juga turut andil dalam peningkatan konsentrasi CO₂ di atmosfir. Meningkatnya emisi CO₂ menyebabkan turut meningkatnya suhu bumi dan perubahan iklim yang disebabkan oleh ‘efek rumah kaca’. Sehingga, konversi CO₂ menjadi senyawa yang lebih bermanfaat sangatlah diperlukan. Dalam penelitian ini, dilakukan sintesis dan karakterisasi karbon mesopori termodifikasi NiZn sebagai katalis heterogen reaksi karboksilasi asetilena dengan CO₂. Karbon mesopori disintesis dengan metode soft template menggunakan surfaktan pluronik F127 sebagai template organik, serta phloroglucinol sebagai prekursor karbon. Karbon mesopori kemudian dimodifikasi dengan logam nikel dan seng (NiZn/MC) dengan metode deposisi-presipitasi homogen, dilanjutkan dengan reduksi dengan aliran gas H₂ (30 ml per menit) selama 90 menit pada suhu 400 ^oC. Pola difraksi XRD menunjukkan puncak-puncak pada 2q sekitar 31,79^o; 34,54^o; 36,31^o; 44,04^o; 51,51^o; 56,51^o; 62,22^o; dan 75,68^o yang mengindikasikan terdapatnya spesi NiZn dan ZnO. Berdasarkan hasil EDX, material karbon mesopori berhasil dimodifikasi dengan logam nikel dan seng dengan persen loading 11,68%, untuk nikel dan 8,69% untuk logam seng. Katalis NiZn/MC kemudian digunakan sebagai katalis heterogen dalam reaksi karboksilasi asetilena dengan CO₂. Reaksi dilakukan dalam reaktor batch dengan kondisi reaksi yang bervariasi, yakni tekanan 1,5 bar; 2,5 bar; dan 3,5 bar. Asam akrilat, sebagai produk yang diinginkan, tidak terdeteksi pada analisis dengan HPLC. Namun, terdeteksi spesi yang lebih polar pada waktu retensi 3 menit, di mana kondisi optimum terjadi pada tekanan 2,5 bar. ...... Utilization of fossil fuel, charcoal, oil, and natural gases, which are carbon-rich materials, is widely used for human sustainability. However, utilization of such materials contributes to higher atmospheric CO₂ concentration. The increase of CO₂ emission leads to higher temperature and climate change ea t ‘green house effect’. Therefore, conversion of CO₂ to value-added chemicals has drawn many attentions. In this research, carboxylation reaction of acetylene and CO₂ has been carried out using mesoporous carbon modified by nickel and zinc metals as heterogeneous catalyst. Mesoporous carbon has been successfully synthesized using soft template method with pluronic F127 as template and phloroglucinol as carbon precursor. Mesoporous carbon was then modified with nickel and zinc (NiZn/MC) using homogeneous deposition precipitation method, followed by reduction for 90 mins at 400 ^oC under a flow of H₂ (30 ml/min). XRD diffraction pattern showed peaks for 2q around 31.79^o, 34.54^o, 36.31^o, 44.04^o, 51.51^o, 56.51^o, 62.22^o, and 75.68^o which indicate the presence of NiZn and ZnO. EDX result revealed that mesoporous carbon material has been successfully modified by nickel and zinc metals, with 11.68% and 8.69% metal loadings for nickel and zinc, respectively. NiZn/MC catalyst was then used for carboxylation reaction of acetylene with CO₂. The reactions were carried out in batch reactor with varied pressure, 1.5 bar, 2.5 bar, and 3.5 bar. Acrylic acid, as the desired product, was not observed in analysis with HPLC. However, more polar species was noticed at retention time of 3 minutes, where optimum pressure was found to ea t 2.5 bar.

Abstrak :
Lignoselulosa merupakan sumber biomassa yang melimpah, namun belum banyak dimanfaatkan. Sumber lignoselulosa yang keberadaanya cukup melimpah di Indonesia salah satunya adalah limbah kayu mahoni. Selulosa sebagai salah satu komponen utama lignoselulosa limbah kayu mahoni berpotensi dikonversi menjadi asam levulinat, yang merupakan salah satu platform chemical. Konversi selulosa limbah kayu mahoni menjadi asam levulinat dilakukan dengan mereaksikan selulosa dalam kondisi asam, dengan bantuan katalis heterogen Mn/ZSM-5 mesopori dan reagen mirip fenton. Oleh karena itu, peneliti melakukan studi optimasi reaksi konversi selulosa hasil delignifikasi limbah kayu mahoni menjadi asam levulinat. Kandungan lignin limbah kayu mahoni diturunkan melalui pretreatment secara bertahap: (1) delignifikasi dengan alkali NaOH dan (2) delignifikasi oksidatif dengan NaOCl. Pretreatment dengan NaOH berhasil menurunkan kadar lignin dari 31,82% menjadi 15,58%, dan dengan NaOCl kadar lignin turun lingga 6,4%. Reaksi konversi selulosa dari limbah kayu mahoni dilakukan dengan katalis heterogen Mn/ZSM-5 mesopori dalam sistem mirip fenton. Selulosa melalui dua tahap reaksi agar dapat memproduksi asam levulinat, yaitu hidrolisis menjadi glukosa dan didehidrasi menjadi asam levulinat. Mesoporisitas katalis Mn/ZSM-5 cukup selektif memproduksi asam levulinat karena tidak dihasilkan produk intermediet HMF. Konsentrasi H3PO4 dan H2O2 yang paling optimum yaitu 40% dan 30% secara berturut-turut, dengan % konversi selulosa kayu mahoni menjadi asam levulinat yaitu 1,89% pada jam ke-8 pada optimasi untuk H3PO4 dan % konversi α-selulosa menjadi asam levulinat pada optimasi H2O2 yaitu 2,44%. ...... Lignocelluloses is one of biomass source abundance on earth. One of the most abundance lignocelluloses source in Indonesia is mahogany waste wood. Cellulose as the main content of mahogany waste wood can be converted into levulinic acid that has been known as platform chemical. Cellulose from mahogany waste wood into levulinic acid is performed in acidic condition, with mesoporous Mn/ZSM-5 catalyst and fenton-like reagent Therefore, it is important to know the optimization reaction of delignified cellulose conversion from mahogany waste wood into levulinic acid. Lignin constituent within mahogany waste wood is decreased by two steps pretreatment: (1) delignification by alkaline NaOH and (2) oxidative delignification using NaOCl. Alkaline pretreatment and NaOCl pretreatment reduced lignin into 15,58% (%wt), and 6,4% (%wt) respectively from its original level of 31,82%. Reaction held with heterogenous Mn/ZSM-5 catalyst in fenton-like system. Cellulose conversion occur in two steps: hydrolysis of cellulose into glucose and dehydration of glucose into levulinic acid. Mesoporpus catalyst Mn/ZSM-5 is proven to be selective catalyst, because there is no intermediate product of HMF. H3PO4 and H2O2 concentration to produce optimum conversion are 40% and 30% respectively, with % conversion of cellulose of mahogany waste wood into levulinic acid are 18,89% and 24,51% using optimization of H3PO4 and H2O2 respectively.