| Alterations of the surface and morphology of tetraalkyl-ammonium modified montmorillonites upon acid treatment. | |
| | |
MedLine Citation:
|
PMID: 21820667 Owner: NLM Status: Publisher |
Abstract/OtherAbstract:
|
The effect of short alkyl chain cations on the modification of the structure, surface and textural properties of organo-montmorillonites upon their acid treatment was investigated. Samples prepared from Ca-SAz montmorillonite and tetramethylammonium (Me(4)N(+)-), tetraethylammonium (Et(4)N(+)-), tetrapropylammonium (Pr(4)N(+)-) and tetrabutylammonium (Bu(4)N(+)-) salts were treated in 6M HCl at 80°C for 2-8h and analyzed by different methods. Acid treatment of organo-montmorillonites caused gradual release of Al and Mg from the octahedral sheets and destruction of their layered structure. The extent of the changes depended significantly on the size of organo-cation. While large plate-like particles of Ca-SAz and Me(4)N-SAz were disintegrated during acid treatment and smaller fine grains were created, the morphology of Bu(4)N-SAz was modified only slightly. Pore size analysis showed generation of pore network upon organo-montmorillonites dissolution. After longer acid attack, pore volume increased and pore size distribution curves were shifted to pores with diameter above 25Å. The surface area of acid-treated samples increased due to destruction of the montmorillonite layers and formation of the SiO(2)-rich reaction product. The highest value 475m(2)/g was observed for Me(4)N-SAz treated 4h. Surface area of Et(4)N-SAz, Pr(4)-SAz and Bu(4)N-SAz was 441, 419 and 293m(2)/g, respectively, after 8h treatment. Similar decomposition level was observed for Ca-SAz and Me(4)N-SAz, and less destruction was found for Et(4)N-SAz, Pr(4)-SAz and very low for Bu(4)N-SAz. Though Bu(4)N(+) is short alkyl chain cation, its size is large enough to cover the inner and outer surfaces of montmorillonite and thus to protect the clay layers from acid attack. |
| | |
Authors:
|
Helena Pálková; L'uboš Jankovič; Małgorzata Zimowska; Jana Madejová |
Related Documents
:
|
490547 - Structural analogues of l-glutamic acid gamma-(4-hydroxyanilide) and gamma-(3,4-dihydro... 16866477 - New protonation microequilibrium treatment in the case of some amino acid and peptide d... 6146137 - The ferrier lecture, 1983. amino acids and peptides: fast and slow chemical signals in ... 10028257 - Novel characteristic for distinguishing lactococcus lactis subsp. lactis from subsp. cr... 512637 - Regular arrangement of wall polymers in staphylococci. 10069037 - Significant role of the nitrogen recycling system through the ceca occurs in protein-de... |
Publication Detail:
|
Type: JOURNAL ARTICLE Date: 2011-7-20 |
Journal Detail:
|
Title: Journal of colloid and interface science Volume: - ISSN: 1095-7103 ISO Abbreviation: - Publication Date: 2011 Jul |
Date Detail:
|
Created Date: 2011-8-8 Completed Date: - Revised Date: - |
Medline Journal Info:
|
Nlm Unique ID: 0043125 Medline TA: J Colloid Interface Sci Country: - |
Other Details:
|
Languages: ENG Pagination: - Citation Subset: - |
Copyright Information:
|
Copyright © 2011 Elsevier Inc. All rights reserved. |
Affiliation:
|
Institute of Inorganic Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, 845 36 Bratislava, Slovakia. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
|
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: In situ aqueous derivatization and determination of non-steroidal anti-inflammatory drugs by salting...
Next Document: Effect of particle surface selectivity on composite nanostructures in nanoparticle/diblock copolymer...