Synthesis and Borate Uptake of Two Novel Chelating Resins

We examined the synthesis and borate uptake of novel chelating resins, named MGR and HMR, derived from the functionalization of macroporous poly(glycidyl methacrylate- co -trimethylolpropane trimethacrylate) matrixes with N -methyl- d -glucamine (MG) and 2-amino-2-(hydroxymethyl)-1,3-propanediol (HM), respectively. The structures of free matrixes, resins, and borate-loaded resins were confirmed by infrared spectroscopy. The borate uptake depends significantly on the proton capacity, which is proportional to the GMA fraction in matrixes, but little on the pore structure of macroporous matrixes. The ion-exchange isotherms of borate on MGR and HMR follow the Langmuir equation. MGR shows a larger uptake capacity toward borate than does HMR, comparable to that of Diaion CRB 02, because the tetradentate coordination mode of the former is more stable than the bidentate one of the latter. MGR exhibits a higher rate of borate uptake than does Diaion CRB 02, and the uptake kinetics are explained from a macropore diffusion model.