of ZSM-5 Zeolite Received May 27, 2020
on the economic benefits of refineries. Moreover, in the ... 2.3 Traditional in-situ hydrothermal synthesis of ZSM-5 molecular sieve The steps of synthesis of ZSM-5 molecular sieve were as follows ...
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Synthesis and Characterization of a New …
A novel structure aluminosilicate molecular sieve, named BUCT-3, was prepared by dynamic hydrothermal synthesis, and the critical factor to obtain the new structure is using an active silicon and aluminum source, aluminosilica …
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Properties of molecular sieve membranes
A molecular sieve is a material that can separate molecules based on size and shape. A subgroup of molecular sieves is zeolites. These minerals are natural and ... Zeolites are commonly prepared by hydrothermal treatment in a synthesis mixture. The synthesis mixture mostly contains; water, a silica source, an alumina
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Synthesis of borosilicate TON-framework type molecular sieves
technical field [0001] The present disclosure relates to the use of 1,3-dimethylimidazolium cation or 1,4-bis(N-methylimidazolium)butane divalent cation (1,4-bis(N-methylimidazolium) butanedication) as a structure-directing agent for the synthesis of borosilicate TON framework molecular sieves. Background of the invention [0002] Molecular sieves are a …
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Microwave-Assisted Hydrothermal Synthesis of SBA-15 …
Recently, the micro-wave-assisted hydrothermal synthesis (MAHS) method has been successfully applied to synthesize some molecular sieves, such as AlPO4-55, Beta6, MCM-417, Y8, ZSM …
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Improvement of hydrothermal stability of MCM-41 …
The recent development of the mesoporous molecular sieve MCM-41 by the workers of Mobil 1,2 has attracted much attention because of the potential of these materials for use as
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Synthesis of Nanosized NaY Molecular Sieve under Dynamic Hydrothermal
Nanosized NaY molecular sieves with high crystallinity was synthesized using sodium silicate solution (industrial water glass) without the presence of additive via dynamic hydrothermal method. The influences of aging time of the seed-gel, the temperature and route of gelation, and the alkalinity of the feed-stock gel on the grain size, relative crystallinity and framework …
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Shape-controlled synthesis of manganese oxide octahedral molecular …
Cryptomelane-type manganese oxide octahedral molecular (OMS) sieve three-dimensional (3D) nanostructures were synthesized via facile temple-free low-temperature hydrothermal reactions. Morphologies of the cryptomelane-type OMS-2 nanoparticles with tunnel dimension of 4.6 x 4.6 A can be tuned by vary …
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Hydrothermal Synthesis of New Pure Beryllophosphate Molecular Sieve
A few new pure beryllophosphate molecular sieves have been hydrothermally synthesized by using concentrated amines such as triethylene tetramine, polyethylene polyamine, piperazine, and pyridine as structure-directing agents. The structures of these compounds were characterized by single-crystal X-ray diffraction. Their structures are similar to the zeolite gmelinite, gismondine, …
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Conventional hydrothermal synthesis of nanoporous …
Nanoporous molecular sieve 13X was successfully synthesized through the conventional hydrothermal method by using sodium aluminates as Al source and water-glass …
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NEW DIRECTIONS IN MOLECULAR SIEVE SCIENCE AND …
molecular sieve family represents more than two dozen crystal structures and about 200 chemical compositions. The aluminophosphate-based molecular sieves are synthesized by …
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Conventional hydrothermal synthesis of nanoporous molecular sieve …
Nanoporous molecular sieve 13X was successfully synthesized through the conventional hydrothermal method by using sodium aluminates as Al source and water-glass solution as an economic reagent for Si source. The hydrothermal reaction was performed under a static condition in an air oven maintained at 90 ± 5 °C for 24 h. Nano molecular sieve was …
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Synthesis of SAPO-34 Molecular Sieves via Novel …
In the MTO reaction, the SAPO-34 molecular sieve has been considered to be a uniquely effective catalyst for the conversion of methanol to olefins with high catalytic activity and selectivity, due to its appropriate small …
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Zeolite and molecular sieve synthesis
Zeolite and molecular sieve syntheses are reviewed. The synthesis of aluminum-rich zeolites, high-silica zeolites, and phosphate-based molecular sieves are evaluated. Unresolved mechanistic issues are outlined and areas for exploration suggested. The ability to plan zeolite and molecular sieve syntheses is discussed and a strategy for synthesizing a chiral zeolite is …
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Key parameters in hydrothermal synthesis and …
Nanomaterials, 2021. Two-dimensional SAPO-34 molecular sieves were synthesized by microwave hydrothermal process. The concentrations of structure directing agent (SDA), phosphoric acid, and silicon in the gel solution were varied and their effect on phase, shape, and composition of synthesized particles was studied.
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Study on the Synthesis of LTA-Type Molecular Sieves from …
Coal gangue and aluminum ash emerge as quintessential constituents within the ambit of coal-derived solid waste and industrial residue, respectively. Leveraging coal gangue as a primary substrate and aluminum ash as an adjunct aluminum source, molecular sieves can be synthesized through hydrothermal means. By modulating the dosage of aluminum ash, …
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Review Mesoporous molecular sieve-based materials for …
Controllable synthesis of mesoporous molecular sieves with different properties can be achieved by changing the types of surfactants or block copolymers and the synthesis conditions. ... Zhao et al. (2010) synthesized Al-HMS by hydrothermal method, and then impregnated with 0.9 wt.% Pd to obtain Pd/Al-HMS (Si/Al molar ratio of 50) to be applied ...
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Microwave-Assisted Hydrothermal Synthesis of SBA-15 …
Synthesis of SBA-15 molecular sieve by microwave-hydrothermal synthesis method: Microwave-hydrothermal synthesis of SBA-15 molecular sieve was performed using a LG WD900 [MG-5515SD, LG Electronics (Tianjin) Appl. Co., Ltd., China] domestic microwave ovens. The experiment was operated under a maximum power
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Cationic Surfactant-Assisted Hydrothermal Synthesis: an Effective …
Herein, we summarize the work on the seed-assisted synthesis of AlPO/SAPO molecular sieves compared with the zeolite synthetic system, aiming to prompt the synthesis and application of AlPO/SAPO ...
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Synthesis of MCM-41 mesoporous molecular sieves based …
This paper presents an innovative approach to the high-value utilization of recycled glass fibers as Si and Al sources for the synthesis of Si–Al MCM-41 mesoporous molecular sieves by the alkali fusion–hydrothermal method.
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Organotemplate-Free Hydrothermal Synthesis of Isomorphously …
An organotemplate-free hydrothermal route was investigated for synthesizing isomorphously Co-substituted mordenite molecular sieve using only the inorganic raw materials such as sodium silicate ...
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Microwave-Assisted Hydrothermal Synthesis of SBA-15 …
In the present study, SBA-15 molecular sieve was successfully synthesized by a microwave-assisted hydrothermal synthesis method, using poly (ethylene glycol)-block-poly …
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Two-Step Hydrothermal Synthesis of …
A submicrometric and hierarchical hollow SAPO-34 molecular sieve was synthesized by an easy and low-cost two-step hydrothermal method. First, the crystallized mixture was obtained by direct drying after a first-step …
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Hydrothermal Synthesis of Structure‐ and …
Highly uniform single‐crystal Na‐OMS‐2 (OMS: octahedral molecular sieve), pyrolusite, and γ‐MnO2 nanostructures with an interesting 3D urchinlike morphology have been successfully prepared using a hydrothermal method based on a mild and direct reaction between sodium dichromate and manganese sulfate. The crystal phases, shapes, and tunnel sizes of …
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Direct synthesis of titanium-substituted mesoporous SBA-15 molecular …
Titanium-substituted mesoporous SBA-15 molecular sieve has been successfully prepared at 373 K by direct synthesis under microwave - hydrothermal conditions within about 2 h. By means of X-ray diffraction, nitrogen adsorption, infrared, UV - vis diffuse reflectance, and Raman spectroscopies, a successful isomorphous substitution of titanium in ...
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Hydrothermal synthesis of alkali cation heulandite …
ELSEVIER Hydrothermal synthesis of alkali cation heulandite aluminosilicate molecular sieves Dongyuan Zhao and Larry Kevan Department of Chemisty, University of Houston, Houston, Texas, USA Rosemarie Szostak Department of Chemistry, Clark Atlanta University;, Atlanta, Georgia, USA Heulandite molecular sieves with a SVAI ratio of 3.2 -3.8 …
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Synthesis and mechanism of porous molecular sieves
Chemical agents or hydrothermal treatment can also be used to remove aluminum from the skeleton of the molecular ... synthesis of molecular sieve [16] : (1) structure-oriented
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Hydrothermal synthesis of nanosized SAPO-34 molecular …
Silicoaluminophosphate molecular sieves were hydrothermally synthesized by using different combinations of TEAOH, morpholine, DEA and TEA as SDAs. The results …
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Solventless synthesis of AEL-type aluminophosphate molecular sieve …
Javier Perez-Ramirez and co-workers recently reviewed the benefits of (seed) milling as a tool for preparing and "activating" precursor mixtures prior to their hydrothermal treatment for molecular sieve synthesis. A lot of advantages of this mechanochemical process had been demonstrated in a series of studies [13].
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Synthesis of mesoporous silicate molecular sieves by the …
There are three main methods for the synthesis of mesoporous molecular sieves: the sol–gel method, the hydrothermal synthesis method and the phase transition method [24–27]. However, there are some problems with these methods, such as low product yield, a large amount of template agent and high production cost and serious wastewater ...
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