Eco-friendly synthesis of high silica zeolite Y with choline as green and innocent structure-directing agent

Two dealuminated β-zeolites, zeolite Y and MCM-22 as well as silicalite, MCM-41 and AlPO4-5 have been studied as hydrophobic adsorbents in water solutions. Dealuminated β-zeolite, MCM-22 and silicalite all adsorb alcohols from water solutions. Enhanced adsorption is obtained for alcohols with longer alkyl chains. Adsorption in the practically most interesting 10–80% range of zeolite filling may adequately be described by Langmuir isotherms. The Langmuir adsorption constants are similar for β-zeolite, MCM-22 and silicalite. This indicates that the adsorption is independent of the pore structure for the alcohols tested in this study. The surface silanol density is however important, such that a low SiOH density is required to give lipophilic properties. In line with this, dealuminated zeolite Y, as prepared here, and MCM-41 give only a poor preference for alcohols from water. For the β-zeolite, the dealumination procedure is important for retaining the micropore volume and adsorption capacity of the zeolite. AlPO4-5 shows no potential as an adsorbent for alcohols from water solutions.

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Influencing factors on rapid crystallization of high silica nano-sized zeolite Y without organic template under atmospheric pressure

Journal of Porous Materials ◽

10.1007/s10934-008-9200-4 ◽

2008 ◽

Vol 16 (3) ◽

pp. 299-306 ◽

Cited By ~ 30

Author(s):

Young Chang Kim ◽

Ji Yeon Jeong ◽

Ji Yeong Hwang ◽

Shin Dong Kim ◽

Wha Jung Kim

Keyword(s):

Influencing Factors ◽

Atmospheric Pressure ◽

Zeolite Y ◽

Organic Template ◽

Rapid Crystallization ◽

High Silica

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Enhanced Catalytic Performance of the FCC Catalyst with an Alumina Matrix Modified by the Zeolite Y Structure-Directing Agent

Industrial & Engineering Chemistry Research ◽

10.1021/acs.iecr.8b04890 ◽

2019 ◽

Vol 58 (14) ◽

pp. 5455-5463

Author(s):

Mengjie Xie ◽

Yifang Li ◽

Ubong Jerome Etim ◽

He Lou ◽

Wei Xing ◽

...

Keyword(s):

Zeolite Y ◽

Catalytic Performance ◽

Alumina Matrix ◽

Structure Directing Agent ◽

Fcc Catalyst

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Sulfonamide Antibiotics Embedded in High Silica Zeolite Y: A Combined Experimental and Theoretical Study of Host−Guest and Guest−Guest Interactions

Langmuir ◽

10.1021/la9049132 ◽

2010 ◽

Vol 26 (12) ◽

pp. 9524-9532 ◽

Cited By ~ 43

Author(s):

Ilaria Braschi ◽

Giorgio Gatti ◽

Geo Paul ◽

Carlo E. Gessa ◽

Maurizio Cossi ◽

...

Keyword(s):

Theoretical Study ◽

Zeolite Y ◽

Sulfonamide Antibiotics ◽

High Silica

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Floating Adsorbent for Organic Removal Fabricated Through Crystallization of Silicalite-1 on Hollow Glass Microspheres

Science of Advanced Materials ◽

10.1166/sam.2020.3622 ◽

2020 ◽

Vol 12 (2) ◽

pp. 173-179 ◽

Cited By ~ 1

Author(s):

Supinya Nijpanich ◽

Takeshi Hagio ◽

Yuki Kamimoto ◽

Ryoichi Ichino

Keyword(s):

Hydrothermal Synthesis ◽

Crystallization Rate ◽

Glass Microspheres ◽

Hollow Glass Microspheres ◽

Structure Directing Agent ◽

Hollow Glass ◽

Key Factor ◽

Type Zeolite ◽

High Silica ◽

Filter Clogging

MFI-type zeolite is a crystalline microporous aluminosilicate with an intersecting two-dimensional pore structure and well-defined windows of approximately 0.55 nm. It generally crystallizes in high silica to alumina ratios, leading to a rather hydrophobic character. This makes it an attractive adsorbent for removing organic pollutants from wastewater. However, separating the conventional powdery-zeolites from the media after treatment is difficult because they require considerable time to settle. They also trigger filter clogging. In this work, high silica MFI-type zeolite, namely, silicalite-1, was synthesized on the surfaces of hollow glass microspheres to develop a floating adsorbent with high hydrophobicity. Tetraethylorthosilicate and tetrapropylammonium hydroxide were used as the additional silica source and structure directing agent, respectively. The crystallization of silicalite-1 on hollow glass microspheres was performed using hydrothermal synthesis at 180 °C or 150 °C for 40 h using a precursor sol with a molar composition of 3SiO2:1TPA:14EtOH:286H2O. The surface coverage and crystallinity of the as-prepared samples were optimized, and the floatability and adsorption performance of the optimized sample were investigated. Well-covered microspheres were obtained when hydrothermal synthesis was conducted at 180 °C using 0.5 g of hollow glass microspheres and 15 g of a precursor sol adjusted to pH 12.5. The balance between the dissolution rate of the hollow glass microspheres and the crystallization rate of silicalite-1 appeared to be the key factor in the successful synthesis.

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Syntheses of high-silica zeolites in urea/choline chloride deep eutectic solvent

Canadian Journal of Chemistry ◽

10.1139/cjc-2016-0115 ◽

2016 ◽

Vol 94 (6) ◽

pp. 533-540 ◽

Cited By ~ 6

Author(s):

Zheng Sonia Lin ◽

Yining Huang

Keyword(s):

Choline Chloride ◽

Deep Eutectic Solvent ◽

Reaction Times ◽

Ammonium Ion ◽

Structure Directing Agent ◽

Nmr Spectrum ◽

Local Ordering ◽

High Silica ◽

High Silica Zeolites ◽

Urea Decomposition

This paper presents the first example of high-silica and siliceous zeolite synthesis in the urea/choline chloride mixture as a deep eutectic solvent (DES) using F– as the mineralizing agent. A urea/choline chloride mixture was previously used as solvent to prepare AlPO4-based microporous materials SIZ-2 and AlPO-CJ2. However, generating these materials depends on the formation of ammonium ion as a structure-directing agent (SDA) that is the side product of urea decomposition. In the present study, we show that several highly siliceous zeolites with targeted topologies (MFI, BEA, MEL, and MTN) can be purposely synthesized by adding SDAs of choice rather than relying on solvent decomposition. The Si atoms in zeolite Beta synthesized in a urea/choline chloride mixture exhibit exceptionally high local ordering as shown in a 29Si MAS NMR spectrum. The synthesis of ZSM-11 using eutectic solvents or ionic liquid has not been reported. The major challenge in ZSM-11 synthesis is the intergrown structure formed with ZSM-5 due to the high similarity in their topologies. The present work shows that preparation of pure ZSM-11 can be achieved in urea/choline chloride DES using either DPHMII or DECDMPI as SDA. Using a urea/choline chloride mixture rather than alcohol-based traditional nonaqueous solvents is the key for the success of preparing phase-pure ZSM-11 free of any MFI intergrowths. This is because some alcohols can serve as SDA for MFI. The use of urea/choline chloride based DES eliminates the potential templateing effect of solvent for MFI formation. For MTN zeolite, morphology may be controlled in urea/choline chloride by choosing different SDAs. The disadvantage of this system is the long reaction times.

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Synthesis of high-silica ZSM-5 with seeds in the presence of ethanol and amine

Cerâmica ◽

10.1590/0366-69132019653752705 ◽

2019 ◽

Vol 65 (375) ◽

pp. 378-387

Author(s):

T. R. D. Mendonça ◽

J. R. Santos ◽

L. R. A. Sarmento ◽

D. C. M. Silva ◽

O. M. S. Cysneiros ◽

...

Keyword(s):

Crystallite Size ◽

Organic Compounds ◽

Nitrogen Adsorption ◽

Structure Directing Agent ◽

X Ray ◽

Synthesis Conditions ◽

Combined Use ◽

Cracking Reaction ◽

High Silica ◽

Alternative Structure

Abstract The possibility of crystallization of ZSM-5 with high Si/Al ratio was evaluated through the combined use of crystallization seeds and organic compounds that are not conventional directing agents for ZSM-5 (ethanol, methylamine, ethylamine, propylamine, butylamine, isopropylamine and diethylamine) in order to find a less toxic and costly route of synthesis. In addition, the influence of the stirring during the crystallization step on the properties of the ZSM-5 obtained in these synthesis conditions was verified. The obtained zeolites were analyzed by X-ray diffractometry in order to understand the effects of the templates. The analyses of NH3-TPD, nitrogen adsorption, SEM, and TG/DTA were performed for the samples with better crystallinity. The procedure was successfully employed for the synthesis of MFI samples using propylamine as an alternative structure-directing agent. Its mean crystallite size ranged from 23 to 24 nm and was efficient in the cracking reaction of n-hexane.

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