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Title: Mesoporous aluminosilicate ropes with improved stability from protozeolitic nanoclusters

Abstract

Mesoporous aluminosilicate ropes with improved hydrothermal stability have been prepared through S{sup +}X{sup -}I{sup +} route via self-assembly of protozeolitic nanoclusters with cetyltrimethylammonium bromides (CTAB) template micelles in HNO{sub 3} solution. SEM observation confirmed that high-yield aluminosilicate ropes could be produced under proper HNO{sub 3} concentration. NO{sub 3} {sup -} ions had strong binding strength to the CTA{sup +} ions and tended to form more elongated surfactant micelles, thus fibrous products were fabricated under the direction of these long rod micelles in shearing flow. At the same time, the NO{sub 3} {sup -} ions combining with CTA{sup +} ions generated more active (CTA{sup +}NO{sub 3} {sup -}) assembly, which effectively catalysed the polymerization of protozeolitic nanoclusters with large volume into highly ordered mesostructures. Compared with normal MCM-41 silica synthesized through S{sup +}X{sup -}I{sup +} route in acidic media, the hydrothermal stability was improved considerably. These protozeolitic nanoclusters survived strongly acidic media and entered into mesostructured framework, which contributed to the improvement of hydrothermal stability. - Graphical abstract: Mesoporous aluminosilicate ropes with enhanced hydrothermal stability were fabricated from protozeolitic nanoclusters through S{sup +}X{sup -}I{sup +} route in HNO{sub 3} solution under the direction of CTAB templates.

Authors:
 [1];  [2];  [1];  [1];  [1];  [3];  [4]
  1. Shanghai Research Institute of Petrochemical Technology, SINOPEC, Shanghai 201208 (China)
  2. (China)
  3. State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001 (China)
  4. State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001 (China), E-mail: mesozheng@hotmail.com
Publication Date:
OSTI Identifier:
21015684
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 180; Journal Issue: 2; Other Information: DOI: 10.1016/j.jssc.2006.11.017; PII: S0022-4596(06)00598-6; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; BROMIDES; NANOSTRUCTURES; NITRATES; NITRIC ACID; NITROGEN OXIDES; POLYMERIZATION; SCANNING ELECTRON MICROSCOPY; SILICA; STABILITY; ZEOLITES

Citation Formats

Zheng Junlin, State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, Kong Dejin, Yang Weimin, Xie Zaiku, Wu Dong, and Sun Yuhan. Mesoporous aluminosilicate ropes with improved stability from protozeolitic nanoclusters. United States: N. p., 2007. Web. doi:10.1016/j.jssc.2006.11.017.
Zheng Junlin, State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, Kong Dejin, Yang Weimin, Xie Zaiku, Wu Dong, & Sun Yuhan. Mesoporous aluminosilicate ropes with improved stability from protozeolitic nanoclusters. United States. doi:10.1016/j.jssc.2006.11.017.
Zheng Junlin, State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, Kong Dejin, Yang Weimin, Xie Zaiku, Wu Dong, and Sun Yuhan. Thu . "Mesoporous aluminosilicate ropes with improved stability from protozeolitic nanoclusters". United States. doi:10.1016/j.jssc.2006.11.017.
@article{osti_21015684,
title = {Mesoporous aluminosilicate ropes with improved stability from protozeolitic nanoclusters},
author = {Zheng Junlin and State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001 and Kong Dejin and Yang Weimin and Xie Zaiku and Wu Dong and Sun Yuhan},
abstractNote = {Mesoporous aluminosilicate ropes with improved hydrothermal stability have been prepared through S{sup +}X{sup -}I{sup +} route via self-assembly of protozeolitic nanoclusters with cetyltrimethylammonium bromides (CTAB) template micelles in HNO{sub 3} solution. SEM observation confirmed that high-yield aluminosilicate ropes could be produced under proper HNO{sub 3} concentration. NO{sub 3} {sup -} ions had strong binding strength to the CTA{sup +} ions and tended to form more elongated surfactant micelles, thus fibrous products were fabricated under the direction of these long rod micelles in shearing flow. At the same time, the NO{sub 3} {sup -} ions combining with CTA{sup +} ions generated more active (CTA{sup +}NO{sub 3} {sup -}) assembly, which effectively catalysed the polymerization of protozeolitic nanoclusters with large volume into highly ordered mesostructures. Compared with normal MCM-41 silica synthesized through S{sup +}X{sup -}I{sup +} route in acidic media, the hydrothermal stability was improved considerably. These protozeolitic nanoclusters survived strongly acidic media and entered into mesostructured framework, which contributed to the improvement of hydrothermal stability. - Graphical abstract: Mesoporous aluminosilicate ropes with enhanced hydrothermal stability were fabricated from protozeolitic nanoclusters through S{sup +}X{sup -}I{sup +} route in HNO{sub 3} solution under the direction of CTAB templates.},
doi = {10.1016/j.jssc.2006.11.017},
journal = {Journal of Solid State Chemistry},
number = 2,
volume = 180,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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