Silica Polyamine Composites: New Supramolecular Materials for Cation and Anion Recovery and Remediation
The surface coverage of amorphous silica gels used in the synthesis of silica polyamine composites has been investigated by 29Si NMR. By diluting the polyamine anchor silane, chloropropyl trichlorosilane, with methyl trichlorosilane it was found that surface coverage could be markedly improved for a...
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Published in | Macromolecular symposia Vol. 235; no. 1; pp. 161 - 178 |
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Main Authors | , , , , , , |
Format | Journal Article Conference Proceeding |
Language | English |
Published |
Weinheim
WILEY-VCH Verlag
01.03.2006
WILEY‐VCH Verlag Wiley-VCH |
Subjects | |
Online Access | Get full text |
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Summary: | The surface coverage of amorphous silica gels used in the synthesis of silica polyamine composites has been investigated by 29Si NMR. By diluting the polyamine anchor silane, chloropropyl trichlorosilane, with methyl trichlorosilane it was found that surface coverage could be markedly improved for a range of amine polymers after grafting to the silica surface. The commensurate decrease in the number of anchor points and increase in the number of free amines results in an increase in metal capacity and/or an improvement in capture kinetics. Solid state CPMAS‐13C NMR has been employed to investigate the structure and metal ion binding of a series of these composite materials. It is reported that the highly branched polymer, poly(ethyleneimine) (PEI) exhibits much broader 13C NMR resonances than the linear polymers poly(allylamine) (PAA) and poly(vinylamine) (PVA). These results are understood in terms of the low energy conformations calculated from molecular modeling studies. Three new applications of the technology are also presented: 1) separation of lanthanides as a group from ferric ion and all other divalent ions; 2) a multi step process for recovering and concentrating the valuable metals in acid mine drainage; 3) a process for removing low level arsenic and selenium in the presence of sulfate using immobilized cations on the composite materials. |
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Bibliography: | ArticleID:MASY200650320 istex:A146F72FEF3C7DC1CECBB9291F03DA652A435932 ark:/67375/WNG-DSHB287R-0 ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 content type line 23 ObjectType-Article-1 ObjectType-Feature-2 |
ISBN: | 3527315187 9783527315185 |
ISSN: | 1022-1360 1521-3900 |
DOI: | 10.1002/masy.200650320 |