Recognizing Functional Groups of MES/APG Mixed Surfactants for Enhanced Solubilization toward Benzo[a]pyrene.
Environ Sci Technol
; 58(19): 8565-8575, 2024 May 14.
Article
en En
| MEDLINE
| ID: mdl-38575864
ABSTRACT
Benzo[a]pyrene is difficult to remove from soil due to its high octanol/water partition coefficient. The use of mixed surfactants can increase solubility but with the risk of secondary soil contamination, and the compounding mechanism is still unclear. This study introduced a new approach using environmentally friendly fatty acid methyl ester sulfonate (MES) and alkyl polyglucoside (APG) to solubilize benzo[a]pyrene. The best result was obtained when the ratio of MES/APG was 71 under 6 g/L total concentration, with an apparent solubility (Sw) of 8.58 mg/L and a molar solubilization ratio (MSR) of 1.31 for benzo[a]pyrene, which is comparable to that of Tween 80 (MSR, 0.95). The mechanism indicates that the hydroxyl groups (-OH) in APG form "O-H···OSO2-" hydrogen bonding with the sulfonic acid group (-SO3-) of MES, which reduces the electrostatic repulsion between MES molecules, thus facilitating the formation of large and stable micelles. Moreover, the strong solubilizing effect on benzo[a]pyrene should be ascribed to the low polarity of ester groups (-COOCH3) in MES. Functional groups capable of forming hydrogen bonds and having low polarity are responsible for the enhanced solubilization of benzo[a]pyrene. This understanding helps choose suitable surfactants for the remediation of PAH-contaminated soils.
Palabras clave
Texto completo:
1
Base de datos:
MEDLINE
Asunto principal:
Solubilidad
/
Tensoactivos
/
Benzo(a)pireno
Idioma:
En
Revista:
Environ Sci Technol
Año:
2024
Tipo del documento:
Article
País de afiliación:
China