Effect of surface-exposed chemical groups on calcium-phosphate mineralization in water-treatment systems.
Environ Sci Technol
; 44(20): 7937-43, 2010 Oct 15.
Article
en En
| MEDLINE
| ID: mdl-20873736
ABSTRACT
Calcium-phosphate-scale formation on reverse osmosis (RO) membranes is a major limiting factor for cost-effective desalination of wastewater. We determined the effects of various organic chemical groups found on membrane surfaces on calcium-phosphate scaling. Langmuir films exposing different functional groups were equilibrated with a solution simulating the ionic profile of secondary effluent (SSE). Surface pressure-area (Langmuir) isotherms combined with ICP elemental analyses of the interfacial precipitate suggested acceleration of calcium-phosphate mineralization by the surface functional groups in the order PO(4) > COOH â¼ NH(2) > COOHNH(2) (11) > OH > ethylene glycol. Immersion of gold-coated silicon wafers self-assembled with different alkanethiols in SSE solution showed formation of a hydroxyapatite precipitate by X-ray diffraction and ATR-IR analysis. Data showed diverse influences of functional groups on mineralization, implying low calcium-phosphate scaling for uncharged surfaces or surfaces coated with both positively and negatively charged groups. This information is valuable for understanding scaling processes, and for designing of novel low-scaling membranes for water desalination.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Fosfatos de Calcio
/
Agua
Idioma:
En
Revista:
Environ Sci Technol
Año:
2010
Tipo del documento:
Article
País de afiliación:
Israel