Milling Activation for the Solvent‐Free Synthesis of the Zeolite Mordenite (original) (raw)
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Synthesis of Mesoporous Mordenite Zeolite by Different Natural Raw Materials
Mordenite (Si/Al = 12.26) was hydrothermally synthesized from locally available low-cost materials using (Sunflower husk, Seed husk, Popcorn waste and chert rock) as a source of extracted Silica (SiO2) without the addition of a templating agent, seed powder, structure-directing agent, and additives. Chert rock is the best-extracted silica source that can be used in synthesizing mesoporous Mordenite Zeolite by this method, since (Sunflower husk, Seed husk and Popcorn waste) were not obtained a significant amount of silica. The starting material in the reaction temperature 25 ± 2 ° C for 72 h. The synthesized zeolites were characterized by Fourier Transform Infrared (FTIR) spectroscopy. The results obtained using X-ray diffraction (XRD) show moderate average crystal size of 26.65nm and confirm the formation of mordenite zeolite. X-ray Fluorescence (XRF) used to determine the Si/Al ratio and the result also confirmed the formation of mordenite zeolite. Field Emission Scanning Electron Microscopy (FE-SEM) was exploited to find out the morphology of the zeolite product and the result displayed a mixture of multi-faced spherules crystal with an ice hockey shape with different particle diameter along with round amorphous particles. The average pore size, pore volume and surface area were determined by Brunauer-Emmett and Teller (BET) method with values of 26.30 nm, 0.28 mL.g-1 and 254.38m 2 .g-1 respectively. Finally, Transmission Electron Microscopy (TEM) was used to find the average crystal size and shape of zeolite, showing 37.82 nm of its average crystal size. The results verified that mordenite zeolites obtained from the hydrothermal condition, present a good zeolitic property and then can be suitable for using in adsorption ion exchange and catalysis experiments. The properties of zeolite materials formed are strongly depended upon the composition and the type of raw materials used.
Hydrothermal Synthesis of Mordenite Type Zeolite
International Journal of Computational and Experimental Science and Engineering
Zeolite is a crystalline alumino-silicate microporous material, which has been widely used as ion-exchangers, adsorbent and catalyst. Recently, several researches highlights the progress of zeolite-based catalysts in the CO2 conversion to valuable products. In the present work, hydrothermal synthesis of mordenite zeolite crystals, with composition of the chemical products Al2O3, 12.5 SiO2,2.4 NaOH, 110 H2O at 160°C for 96 hours (4 days) at Ph 11 is described. Results of characterization of the mordenite zeolite by XRD, FTIR, EDAX, SEM, TGA, are presented and discussed. In the present work, hydrothermal synthesis and characterization of mordenite zeolite crystals is described.
Journal of Physics: Conference Series, 2019
Mordenite-type zeolites were prepared via hydrothermal method using silica gel and sodium aluminate as Si and Al sources respectively. The temperature was varied from 150°C up to 190°C to determine the minimum temperature to obtain crystalline mordenite using a 23 mL Teflon-lined stainless-steel autoclave. The samples were characterized using XRD, FTIR and SEM. With the given experimental conditions, mordenite-type zeolites with good crystallinity and excellent purity were produced at 190°C. Amorphous materials with notable peaks that correspond to mordenite planes were produced at 170°C. The sample produced at 150°C was completely amorphous. FTIR revealed that all the three samples contain bands associated to aluminosilicate vibrational groups. However, a significant decrease in the intensities of vibration bands associated to hydroxyl (HO-) stretching and water bending were observed as the temperature is decreased. From the SEM, the sample treated at 190°C was composed of particles with strikingly linear edges having an average grain size of~38.0 µm. Most particles are hexagonal in shape. Particle components of the samples synthesized at 170°C and 150°C have irregular sizes and shapes.
Ultrasonic Pretreatment as a Tool for the Preparation of Low-Defect Zeolite Mordenite
ACS Omega
The effects of the ultrasonic (US) pretreatment of synthesis gel for the preparation of mordenite zeolite were studied in comparison with the classical stirring method. Even though the US pretreatment was performed before the hydrothermal crystallization, it significantly affected the properties of the obtained mordenite crystals. The US-assisted procedure resulted in a material with improved textural characteristics, in particular, the micropore volume accessible for nitrogen molecules in the as-made form. On the other hand, mordenite prepared with the classical stirring method demonstrated comparable sorption properties only after a postsynthetic treatment. Moreover, in the case of US-pretreated mordenite, altered crystal shape and more homogeneous morphology were observed. 29 Si magic-angle spinning nuclear magnetic resonance (MAS NMR) demonstrated that the US pretreatment introduced structural changes on the atomic level, resulting in fewer defects (reflected in the number of silanol groups) and less pore blockage (affected by Na + cations) for the as-made sample.
Synthesis of mordenite type zeolite
Zeolites, 1986
The data presented show that the rare earth-exchanged USY zeolites combine the catalytic properties of USY zeolites with those of RE,H-Y. By varying the rare earth input into the zeolite, a series of yield-oriented catalysts can be prepared, each tailored to meet the demand of a particular segment of the refining industry.
Synthesis and morphological studies of nanocrystalline MOR type zeolite material
Journal of Colloid and Interface Science, 2008
A number of nanosize mordenite (MOR) analogues with particle size ranging from 5 to 50 nm were synthesized by the hydrothermal method. The effect of various growth parameters like: alkalinity of the medium, type of silica source, etc. on crystal morphology and the crystal size of MOR type of zeolites was investigated. Specific surface and micropore volume were investigated by the Brunauer-Emmett-Teller (BET) method. XRD, SEM, TEM studies indicate nanosize growth of the MOR type crystals. Electron diffraction patterns confirm the crystalline nature of the nanoparticles and the results of their indexing prove that the material is MOR. These synthesized materials show microporous as well mesoporous character. In the case of MOR material synthesized using sodium silicate, it was found that an increase in the alkalinity of the medium led to changes in the morphology and crystal size of the material. For low concentrations of NaOH, the crystallites were spherical in shape whereas at high concentrations, they were in the shape of nanorods of diameter 25 to 50 nm. The morphology of the MOR material synthesized using tetraethyl orthosilicate (TEOS), on the other hand, did not change when the NaOH concentration was increased beyond 2.0 molar. (P. Sharma). and morphology of zeolite L. Their investigation provides a detailed picture of the effects and interdependence of different variables influencing zeolite crystallization.
Microwave-assisted hydrothermal synthesis of mordenite zeolite: Optimization of synthesis parameters
Microporous and Mesoporous Materials, 2016
Sustainable industrial processes demand rapid and cost-effective synthesis procedures of zeolites. Herein, we report the synthesis zone of pure mordenite (MOR) zeolite under microwave irradiations. Phase purity, crystallinity, and morphology were carefully studied through optimization of synthesis parameters such as crystallization time, aging time and Si/Al ratio. Without the seeds, the organicstructure directing agent (OSDA)-free synthesis of pure MOR crystals was achieved in the shortest time of 12 h. Moreover, the addition of two different OSDAs, namely o-phenylenediamine (OPDA) and tetramethylammonium hydroxide (TEAOH), decreases the crystallization time up to 6 h with the same gel composition. Whereas, minimum crystallization time through conventional heating was 24 h with an OSDA and 48 h without the template. Rectangular and spherical shaped crystals with low aspect ratio were formed under this condition. The same optimized condition was used with different gel compositions (i.e. Si/Al of 15, 25, 50) to crystallize pure MOR. Also, effect of alkalinity was investigated at different Si/Al ratios.