Removal of 17 beta-Estradiol from Groundwater Using Nanoporous Molecularly Imprinted Polymer Adsorbent

A polymer adsorbent specific for 17 beta-estradiol (E2) was prepared by using a molecular imprinting technique. E2 is a female hormone (i.e., estrogen) and it has been recently reported in drinking water resources. In this paper, the writers present a method for the remediation of E2 in ground water by using a molecularly imprinted polymer (MIP) adsorbent. The molecular modeling software (HyperChem 8.0) was used to select best polymer precursors for polymer preparation on the basis of interaction energy scorings. The scanning electron microscopy (SEM) and transmission electron microscopy (TEM) micrographs revealed the existence of nanopores (0.65 to 0.8 nm in diameter) in the polymer because of imprinting. The Fourier transform infrared (FT-IR) spectra of the MIP and non-imprinted polymer (NIP) further confirmed an H-bond formation between the carboxylic acid group of methacrylic acid (MAA) and E2, which was responsible for the selective adsorption of E2. The adsorption capacity and binding affinity of the MIP were determined by using Langmuir and Freundlich isotherm models. The adsorption capacity of the MIP was 96: 75 mg/g this value is twice that of the commercially used activated carbon. The effect of environmental parameters [ such as total dissolved solids (TDS) and pH] on the adsorption removal of E2 was studied for water and for groundwater samples collected from industrial areas. In this study, the writer report, for the first time, the reusability of an MIP adsorbent that retains its adsorption capacity for more than eight cycles. High adsorption capacity and resistance to environmental parameters such as TDS and pH demonstrated the merits of MIP over the single use of activated carbon for the remediation of E2-contaminated water. (C) 2012 American Society of Civil Engineers.