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"Zeolit terstruktur yang menggabungkan mikro- danmesoporositas 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 didesilikasimenggunakan 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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AbstractHierarchical 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 alkalinetreated zeolites were virtually unchanged compared to bothof 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 templateplays an important role in preserving the zeolitic structure during the alkaline treatment. "

"The main problem with the slurry process is the difficulty in recovering the photocatalyst nanoparticle from water following purification. An alternative solution proposed the photocatalyst be immobilized on magnetic carriers, which would allow them to be recollected from the water suspension following treatment using an external magnetic field. Magnetically photocatalyst composites were prepared using simple heteroagglomeration by applying attractive electrostatic forces between the nanoparticles with an opposite surface charge. The Fe3O4/SiO2/TiO2 photocatalysts were synthesized in an aqueous slurry solution containing Fe3O4/SiO2 and TiO2 nanoparticles under pH 5 conditions. Meanwhile, Fe3O4/SiO2 was prepared by a simple procedure via a coprecipitation of iron(II) and iron(III) ion mixtures in ammonium hydroxide and was leached by sodium silicate. The synthesized samples were investigated to determine the phase structure, the magnetic properties, and the morphology of the composites by X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and transmission electron microscopy (TEM), respectively. The results indicated that the composites contained anatase and rutile phases and exhibited a superparamagnetic behavior. Fe3O4/SiO2 particles, which were of the aggregation spherical form at 20 nm in size, were successfully attached onto the TiO2 surface. The catalytic activity of Fe3O4/SiO2/TiO2 composites was evaluated for the degradation of methylene blue under ultraviolet (UV) irradiation. The presence of SiO2 as a barrier between Fe3O4 and TiO2 is not only improves the photocatalytic properties but also provides the ability to adsorb the properties on the composite. The Fe3O4/SiO2/TiO2 (50% containing TiO2 in composite) were able to eliminate 87.3% of methylene blue in water through the adsorption and photocatalytic processes. This result is slightly below pure TiO2, which is able to degrade 96% of methylene blue. The resulting Fe3O4/SiO2/TiO2 composite exhibited an excellent ability to remove dye from water and it is easily recollected using a magnetic bar from the water. Therefore, they have high potency as an efficient and simple implementation for the dye effluent decolorization of textile waste in slurry reactor processes."

"ABSTRAKDua tipe organoclay telah dapat disintesis dengan surfaktan yang berbedasebagai agen penginterkalasi. Surfaktan HDTMABr dan ODTMABr diinterkalasikanke dalam bentonit alam serta dilakukan karakterisasi dengan XRD, FT-IR, dan SEMEDS.Sebelumnya Na-bentonit disintesis kemudian dihitung nilai kapasitas tukarkation dengan metode tembaga amin sebesar 45,35 mek/100gram clay. Variasijumlah KTK digunakan untuk dapat melihat peningkatan besarnya basal spacingdengan difraksi sinar-X. Organoclay 1.0 KTK yang telah disintesis digunakansebagai adsorben fenol, katekol dan benzaldehida kemudian dilakukan pengukurandengan spektrofotometer UV. Perbedaan gugus yang melekat pada cincin benzenmempengaruhi kemampuannya untuk terserap pada bentonit. Dengan bertambahnyagugus hidroksi, maka semakin sulit untuk terserap oleh bentonit. Dan apabilasemakin nonpolar senyawa organik, akan semakin mudah terserap. Dengan semakinpanjang rantai alkil surfaktan, bentonit menjadi lebih hidrofobik sehingga menyeraplebih banyak senyawa nonpolar.

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ABSTRACTTwo types of organoclay have been synthesized using different cationicsurfactants as intercalating agents. HDTMABr and ODTMABr are intercalated intothe interlayer space of sodium-clay. With the CEC value sodium-clay is about 45, 35mek/100gram clay using copper amine method. X-ray diffraction is used to study thecharacteristic of organoclay by its variation of CEC value. The resulting of 1,0 CECorganoclay are used to adsorb the organic molecules. UV spectra of this organicmolecule on filtrate reaction are further confirming adsorptions of both organoclay.The different groups which are binding on phenol, benzaldehide, and catechol havedifferent effect to organoclay. No polar organic molecules are the easier moleculewhich adsorbed on the interlayer clay. The longest alkyls chain surfactant will makemore hydrophobic clay furthermore it could adsorb no polar organic molecules."

"ABSTRAKBentonit alam Merangin Jambi merupakan jenis Ca-bentonit dengan dengankandungan smectit sebesar 91,24%. Pada penelitian ini telah berhasil dilakukanmodifikasi bentonit Merangin Jambi dengan KOH 0,1 M; 0,2; 0,3 M; 0,4 M; dan1 M sebagai katalis reaksi transesterifikasi minyak kelapa sawit untuk produksibiodiesel. Biodiesel adalah metil ester asam lemak yang dihasilkan darialkoholisis minyak hewani atau nabati. Selain itu, diamati juga pengaruh dari suhureaksi, waktu reaksi, rasio mol minyak : metanol, dan jumlah katalis. Persentaseyield metil ester cenderung lebih besar pada suhu reaksi 60 oC, waktu reaksi 2jam, rasio mol minyak dengan metanol 1 : 12, jumlah katalis 3%, dan katalis Nabentonityang dimodifikasi dengan KOH 0,4 M. Katalis hasil regenerasi masihdapat digunakan kembali dengan % yield metil palmitat, metil oleat, dan metillinoleat, berturut-turut sebesar 0,34 %, 1,03 %, dan 3,19%.

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ABSTRACT Natural bentonite from Merangin Jambi is a type of Ca-bentonite with thesmectite content of 91,24%. This study has been performed successfully tomodify bentonite from Merangin Jambi as catalyst for the transesterification ofpalm oil for biodiesel production. Biodiesel is fatty acid methyl esters producedby alcoholysis of animal or vegetable oil. In addition, it was observed the effectsof temperature, reaction time, oil to methanol ratio, catalyst amount, and loadingamount KOH. The max percentage yield of methyl ester was obtained attemperature of 60 oC, reaction time 2 hour, oil to methanol ratio 1 :12, 3% catalystamount, and KOH loading at 0,4 M. Recycle catalyst was used for thetransesterification with the percentage yield of methyl palmitate, methyl oleate,and methyl linoleate respectively 0,34%, 1,03%, and 3,19%."

"In order to enhance adsorption capacity of gibbsite (Al(OH)3 as an adsorbent for the adsorption of phosphate in water, gibbsite was modified through lithium-intercalation. The purification method of Tributh and Lagaly was applied prior to intercalation. The Li-Intercalation was prepared by the dispersion of gibbsite into LiCl solution for 24 hours. This intercalation formed an cationic clay with the structure of [LiAl2(OH)6]+ and exchangeable Cl- anions in the gibbsite interlayer. A phosphate adsorption test using Lithium-intercalated gibbsite (LIG) resulted in optimum adsorption occurring at pH 4.5 with an adsorption capacity of 11.198 mg phosphate/g LIG which is equivalent with 1.04 wt% LIG. The adsorption capacity decreased with decreasing amounts of H2PO4-/HPO4- species in the solution. This study showed that LIG has potential as an adsorbent for phosphate in an aqueous solution with pH 4.5?9.5."