Solid phase extraction of phenolic compounds with trimethylstearylammonium-immobilized cation exchange membranes

• Main Authors: Tien-Yu Wang, 王天佑
• Other Authors: 孫幸宜
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/70997175460450253891

碩士 === 國立中興大學 === 化學工程學系所 === 97 === In this study, cationic octadecyltrimethylammonium surfactant was immobilized onto a strong cation exchange membrane (P and S membrane) to form a hydrophobic membrane for application in the solid phase extraction (SPE) of phenolic compounds. The results indicate that the surfactant counter ion OH- (or OCH3-) could greatly improve the surfactant immobilization performance. Through elemental analysis (EA), the resulted surfactant immobilization percentage (immobilized surfactant amount divided by membrane ion exchange capacity) was <100 % for the feed amount of 150 μmol of octadecyltrimethylammonium oxide (or methoxide), 100 % for 5000μmol, and >100 % for 2000μmol respectively. (V = 20 mL). Phenol, 4-nitrophenol, 4-chloro-3-methylphenol and bisphenol-A were the test analytes and their order of hydrophobicity is bisphenol A (log Kow = 3.32) > 4-chloro-3-methylphenol (log Kow = 3.10) > 4-nitrophenol (log Kow = 1.90) > phenol (log Kow = 1.50). The adsorption of different feed concentrations of phenolic compounds for the membranes with 100 % surfactant immobilization demonstrated an adsorption order of bisphenol A > 4-chloro-3-methylphenol > 4-nitrophenol > phenol, similar to their hydrophobic power. Further more, 100mL bisphenol A (of an initial concentration of 1ppm) was also applied in SPE. A concentrated bisphenol A which was fully recovered could be achieved in the SPE when isopropanol was used.