Preparation and use of magnetic poly(glycidyl methacrylate) resin in drinking water treatment

摘要

Magnetic poly(glycidyl methacrylate) (m-PGMA) was synthesized and characterized, and its efficiency in removing natural organic matter (NOM) and carbamazepine (CBZ) from synthetic water was studied. The effects of factors such as time and m-PGMA dosage on NOM removal were investigated. Furthermore, magnetic ion exchange resin (MIEX?) was used for comparison with m-PGMA in CBZ removal. m-PGMA was found to have a strong magnetic character whose specific saturation magnetization and mass fraction of magnetite were 10.79 emu g ~(-1) and 6.166 wt %, respectively, thus providing additional utility for m-PGMA in slurry form in completely mixed continuous-flow reactors. Lab-scale studies showed that the removal rate rose rapidly with time and reached a pseudo-equilibrium after 30 min. In addition, the highest doses of m-PGMA achieved the highest removal efficiency. After 30 min of contact with 5, 10, and 15 mL L~(-1) of m-PGMA, the removal rates, based on UV absorbance measurements at 254 nm (UV_(254)), were 56%, 67%, and 79%, respectively, whereas the removal rates of dissolved organic carbon (DOC) were 53%, 60%, and 72%, respectively. Additionally, the scale ultraviolet absorbance values (SUVA) decreased during a 30 min contact time, thereby suggesting that the NOM removed by m-PGMA had greater aromatic character. In multiple-loading tests, UV254 removal gradually decreased and achieved 18.39% at 1600 bed volume; it was kept constant at this level. Compared to MIEX?, m-PGMA had a higher CBZ removal rate (27.8% and 34.7% for 20 mL L~(-1) and 25 mL L~(-1) of m-PGMA, corresponding to the removal of 200 μg L ~(-1) CBZ). The resulting higher removal rate of CBZ contributed to stronger adsorption, a higher specific surface area, and larger pore volume.