CONVERSION OF THE LOW QUALITY INDONESIAN NATURALLY-OCCURRING MINERALS INTO SELECTIVE TYPE OF ZEOLITES BY SEED-ASSISTED SYNTHESIS METHOD

An X-ray diffraction (XRD) revealed that Indonesian naturally-occurring mineral from Nanggung, Bogor shows to be a low quality product as it does not seem to contain any zeolite materials. As located in the volcanic area, Indonesia essentially has abundant source of natural zeolites and the country has put much efforts on these treasured materials for export commodity. In order to bring the local natural mineral into high value and to discover whether the mineral has at least zeolitic fragments. we have implemented seed-assisted synthesis to see the possibility of growing zeolite and turn this mineral into high quality. In principle, once the mineral has zeolitic fragment or nuclei, recrystallization of the mineral may occur. By utilizing this mineral as seed in aluminosilicate mother solution, selective mordenite-type (MOR) zeolite can be obtained after hydrothermal treatment. Characterization by XRD showed that this MOR zeolite has high crystallinity and scanning electron microscopy (SEM) depicted the crystal morphology. The natural mineral is conclusively essential for the formation of MOR zeolite by seeding the aluminosilicate mother solution. In the absence of aluminosilicate mother solution, natural mineral can be recrystallized into selective analcime-type (ANA) zeolite. MOR zeolite is known to be useful for several applications such as catalysis whereas ANA zeolite has been considered to be less potential due to relatively small microporosity. Hasil analisis difraksi sinar X (XRD) menunjukkan bahwa mineral alam Indonesia yang berasal dari daerah Nanggung, Bogor memiliki kualitas yang rendah dimana tidak terdapat kandungan material Zeolit. Indonesia yang terletak di kawasan vulkanik memiliki sumber zeolit alam dalam jumlah yang besar dan negara ini telah berusaha untuk menjadikan material ini sebagai komoditi ekspor. Untuk meningkatkan kualitas serta menggali lebih jauh lagi apakah mineral alam ini memiliki setidaknya fragmen atau benih Zeolit, kami telah menerapkan metode sintesis dengan bantuan benih untuk melihat kemungkinan terbentuk atau menumbuhkan material Zeolit dan memberikan mineral ini suatu nilai tambah. Pada prinsipnya, ketika mineral alam memiliki fragmen atau benih Zeolit, rekristalisasi mineral dapat dilakukan. Dengan menggunakan mineral alam sebagai benih Zeolit tipe Mardenit dapat dihasilkan setelah proses hidrotermal. Karakterisasi dengan XRD menunjukkan bahwa zeolit tipe Mordenit yang dihasilkan memiliki kristalinitas yang tinggi, selain itu karakterisasi dengan mikroskopi elektran (SEM) menunjukkan morfologi kristal Zeolit. Hasil ini menunjukkan bahwa keberadaan mineral alam sebagai benih dalam larutan induk aluminosilikat pada metode sintesis penelitian ini, sangat berperan panting dalam pembentukan material Zeolit tipe Mordenit. Sedangkan tanpa adanya larutan induk aluminosilikat, mineral alam tersebut hanya dapat direkristalisasi menjadi material Zeolit tipe Analsim. Material zeolit tipe Mordenit memiliki aplikasi yang lebih leas dan bermanfaat contohnya sebagai katalis, dibandingkan material Zeolit tipe Analsim yang kurang potensial pemanfaatannya karena ukuran mikroporinya yang relatif kecil

Metal-promoted mesoporous ZSM5 for CO methanation to produce synthetic natural gas (SNG)

In recent years, enormous emissions of carbon oxide (CO and CO2) by combustion of fossil and fuel have contributed to the increase in global temperatures and climate changes due to the ‘greenhouse effect’ [1]. In order to solve this problem, production of synthetic natural gas (SNG) from synthetic gas (CO and H2) via methanation process is one of the essential alternatives [2]. Therefore, developing an efficient catalyst formethanation reaction is indispensable. Mesoporous zeolites have been reported to have superiorcatalytic performance with respect to their conventional (purely microporous) zeolites due to the combination features of intrinsic microporosity with an auxiliary mesopore network of inter- or intracrystalline nature [3, 4]. In this study, mesoporous ZSM5 (mZSM5) and a series of metal-promoted mZSM5 for CO methanation were prepared by dual templating and impregnation methods, respectively. The physical properties of the catalysts were characterized with X-ray diffraction (XRD), nitrogen physisorption and Field Emission Scanning Electron Microscopy (FESEM). The catalytic CO methanation was performed on metal-promoted mZSM5 at 423-723 K under atmospheric pressure in the presence of H2. The result showed that the catalytic performance of CO methanation followed the order: Rh/mZSM5 >Co/mZSM5 > Pd/mZSM5 > Zn/mZSM5 at 723 K. The highest activity was observed on Rh/mZSM5 with conversion and selectivity of 94.7% and 86.6%, respectively. This study showed that the addition of metal on mZSM5 can significantly improve the catalytic activity on CO methanation

Characteristics of Heavy Metals Adsorption Cu, Pb and Cd Using Synthetics Zeolite Zsm-5

It is generally known that zeolite has potential for heavy metal adsorption. The objectives of this study were to synthesize and characterize zeolite ZSM-5 and to figure out the adsorption capacity of zeolite ZSM-5 for heavy metals of Cu2+, Pb2+ and Cd2+. Characterization of zeolite ZSM-5 included some variables i.e. crystal structure (XRD), morphology (SEM), specific surface area and total pore volume (N2 physisorption). Adsorption capacity of zeolite ZSM-5 was analysed using a batch system with heavy metals of Cu2+, Pb2+ and Cd2+ in various concentrations (50, 100, 150, 200 and 250 ppm) with contact times 30, 60, 90, 120 and 250 minutes. Adsorption data was calculated by Langmuir and Freundlich isotherm. The results showed that the maximum adsorption capacity of zeolite ZSM-5 against heavy metals of Pb2+, Cu2+, and Cd2+, were 74.07, 69.93 and 60.24 mg g-1, respectively. These indicated that synthetic zeolite ZSM-5 had potential to adsorb heavy metals. The results also suggested that the adsorption capacity was affected by the pore size of zeolite, negative charge of zeolite, diameter of hydrated and electronegative ion

Exceptional Aromatic Distribution in the Conversion of Palm-Oil to Biohydrocarbon Using Zeolite-Based Catalyst

A series of four catalysts, i.e. ZSM-5 (Si/Al = 25) (Z1), a combination of ZSM-5 (Si/Al = 25) and zeolite Y (Si/Al = 25) (Z2), zeolite Y (Si/Al = 25) (Z3), and ZSM-5 (Si/Al = 80) (Z4), was successfully prepared for catalytic cracking of palm oil. All three catalysts utilized silica as a binder without other additional components. Catalytic cracking tests showed that the aromatic distribution was very high, according to the following order: Z4 (98%) > Z1 (90%) > Z2 (84%) > Z3 (60%). It was shown that ZSM-5 promotes the formation of aromatics better than zeolite Y does. From 98% of aromatics products in Z1, 71% were benzene, toluene, and xylene (BTX). It appears that the formation of aromatics needs milder acidity since a higher number of acids extends the cracking reaction, resulting in the formation of more gaseous and heavy aromatics products. The results of this study show potential for the sustainable production of bio-hydrocarbons with exceptional aromatic distributions, which may fulfill the demands of the petroleum, petrochemical, and fine chemical sectors

PENGARUH VARIASI MOL H2O TERHADAP KRISTALINITAS ZEOLIT ZSM-5

Zeolit adalah suatu padatan kristalin berpori dengan tiga dimensi yang strukturnya mengandung aluminosilikat, (SiO4) 4- dan (AlO 4) 5- untuk menurunkan konsentrasi ion logam berat. Sintesis zeolit ZSM-5 dengan proses hidrotermal mempunyai kelemahan yaitu memerlukan suhu tinggi, biaya produksi besar, dan sintesis dalam skala besar sulit dilakukan. Oleh karena itu perlu dilakukan sintesis zeolit ZSM-5 pada suhu rendah. Tujuan penelitian ini adalah mensintesis zeolit ZSM-5 dengan variasi mol H O pada suhu rendah (90°C) sehingga diperoleh precursor larutan encer yang dapat diaplikasikan pada sintesis membran ZSM-5 dengan metoda elektrodeposisi dan mengkarakterisasi produk ZSM-5 dengan XRD. Sintesis zeolit ZSM-5 pada suhu rendah adalah dengan mencampur 0,027 mol NaAlO 2 ; 0,184 molNaOH 50% b/b;  0,093mol TPABr;;2,8 mol Ludox HS-40, dan 21,8 mol H 2 2 O. Selanjutnya  dilakukan pengocokan dengan kecepatan 900 rpm selama 30 menit, kemudian dimasukkan ke dalam oven 90°C selama 4 hari. Padatan putih yang terbentuk dicuci dengan akuades dan dipanaskan pada suhu 60°Cselama 3 jam, serta dikalsinasi pada suhu 550°C selama 8 jam. Sintesis ZSM-5 dilakukan variasi mol H O dan zeolit ZSM-5 yang dihasilkan dikarakterisasi dengan XRD. Hasil penelitian adalah sintesis zeolit ZSM-5 dengan 174,4 mol H 2 O (8x) berbentuk larutan precursor yang encer dan mempunyai kristalinitas 68,69 % yang dapat diaplikasikan pada sintesismembran ZSM-5 dengan metoda elektrodeposisi

Preparation of alkali-activated fly ash-based geopolymer and their application in the adsorption of copper (II) and zinc (II) ions

Alkali activation of fly ash can a promising alternative of the system to improve adsorption capability of fly ash. In finding the best chemical composition of the activator solution, geopolymer has been synthesized using molar ratios of Na2O/SiO2 0.16, 0.3, and 0.5 (Gr1, Gr3, Gr5). The results indicated that the geopolymer synthesized with a ratio molar of Na2O/SiO2 0.3 (Gr3) improved the adsorption properties of fly ash substantially. Gr3 was characterized by BET, XRD, and FTIR. The batch experiment was conducted at the different duration and initial concentrations. The equilibrium sorption data were fitted for the Langmuir and Freundlich equations. The maximum sorption capacities calculated from Langmuir isotherm was 54 mg g-1 and 47 mg g-1 for Cu (II) and Zn (II) respectively. The kinetic data reveal that the pseudo-second order model was appropriate for a description of the kinetic performance

Hierarchically Porous ZSM-5 Synthesized by Nonionic- and Cationic-Templating Routes and Their Catalytic Activity in Liquid-Phase Esterification

Hierarchically porous MFI zeolites (ZSM-5) have been synthesized by hydrothermal treatment in the presence of trialkoxysilylated-derivatives of nonionic poly(oxyethylene) alkyl ether or alkyl quaternary ammonium cation as mesopore-generating agent, along with tetrapropylammonium cation as zeolite structure-directing agent. Powder X-ray diffraction revealed that zeolites have been crystallized, and scanning electron microscopy showed rugged surface morphology that was quite different from conventional ZSM-5. The mesoporosity was confirmed by nitrogen adsorption-desorption measurement showing type IV isotherms with narrow distribution of mesopore diameters. The catalytic activity of these mesoporous ZSM-5 was tested in liquid-phase esterification of benzyl alcohol with hexanoic acid. The conversion of benzyl alcohol on mesoporous ZSM-5 prepared via cationic-templating route was almost 100%, being much higher than on mesoporous ZSM-5 prepared with silylated nonionic surfactant as well as on conventional ZSM-5 with no mesopores. The presence of Brønsted acid sites, together with the mesopores, was responsible for this catalytic conversion, as confirmed by pyridine adsorption monitored by in situ infrared and 27Al magic angle spinning nuclear magnetic resonance spectroscopy

Nanocellulose-based fibres derived from palm oil by-products and their in vitro biocompatibility analysis

Fibres with nanocellulose isolated from oil palm empty fruit bunches (OPEFBs) were produced. Nanocellulose and PVA-nanocellulose fibres were prepared by wet spinning in an acetone coagulation bath without drawing. The addition of nanocellulose was varied from 10% to 30%, to reveal the beneficial effects of nanocellulose content on the properties of produced spun-fibres. Higher concentration of nanocellulose increased the stiffness of spun-fibres. PVA and PVA-bacterial cellulose fibres were also produced as a control and for comparison, respectively. The nanocellulose fibre formed a compact structure, while PVA fibres had hollow structures. The effect of the produced spun-fibres on the biocompatibility of calf pulmonary artery endothelial cells was assayed by an MTT test. Based on the MTT assay the addition of nanocellulose increased the percentage of cell viability of the obtained spun-fibres slightly. These results point towards the use of sustainable sources of nanocellulose as a beneficial and biocompatible fibre material. Keywords: Spun-fibres, nanocellulose, cellulose nanofibers, wet spinning, biocompatibilit

Structural rearrangement of mesostructured silica nanoparticles incorporated with ZnO catalyst and its photoactivity: effect of alkaline aqueous electrolyte concentration

ZnO-incorporated mesostructured silica nanoparticles (MSN) catalysts (ZM) were prepared by the introduction of Zn ions into the framework of MSN via a simple electrochemical system in the presence of various concentrations of NH4OH aqueous solution. The physicochemical properties of the catalysts were studied by XRD, 29Si MAS NMR, nitrogen adsorption-desorption, FE-SEM, TEM, FTIR, and photoluminescence spectroscopy. Characterization results demonstrated that the alkaline aqueous electrolyte simply generated abundant silanol groups on the surface of the catalysts as a consequence of desilication to form the hierarchical-like structure of the MSN. Subsequent restructuring of the silica network by the creation of oxygen vacancies and formation of Si-O-Zn during the electrolysis, as well as formation of new Si-O-Si bonds during calcination seemed to be the main factors that enhanced the catalytic performance of photodecolorization of methyl orange. A ZM prepared in the presence of 1.0 M NH4OH (ZM-1.0) was determined to be the most effective catalyst. The catalyst displays a higher first-order kinetics rate of 3.87 × 10-1 h-1 than unsupported ZnO (1.13 × 10-1 h-1) that prepared under the same conditions in the absence of MSN. The experiment on effect of scavengers showed that hydroxyl radicals generated from the three main sources; reduced O2 at the conduction band, decomposed water at the valence band and irradiated H2O2 in the solution, are key factors that influenced the reaction. It is also noted that the recycled ZM-1.0 catalyst maintained its activity up to five runs without serious catalyst deactivation