Aminated glycidyl methacrylates as a support media for goethite nanoparticle enabled hybrid sorbents for arsenic removal: From copolymer synthesis to full-scale system modeling

Abstract

To achieve short mass transfer zones that enable arsenic removal under high hydraulic loading rates and short empty bed contact times needed for small point-of-use packed bed applications, hybrid media was developed and tested. Cross-linked macroporous glycidyl methacrylate copolymer support media was synthetized, amino modified and in-situ impregnated by goethite nanoparticles via an oxidative deposition in a hydrophilic/hydrophobic (water/xylene) system. The media properties were characterized via scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDS), X-ray diffraction (XRD), and surface area analysis. Arsenic removal capabilities of the hybrid goethite impregnated media were evaluated by conducting batch sorption tests, developing isotherms and simulating the breakthrough curve with a pore surface diffusion model (PSDM), after being verified by a short bed column (SBC) test. The high porous media (ep ≈ 0.7) contained ∼16% of iron and exhibited Freundlich adsorption capacity parameter of K ≈ 369 (μg g−1)(L μg−1)1/n and Freundlich intensity parameter of 1/n ≈ 0.54. Without engaging in taxing pilot scale testing, the PSDM was able to provide a good prediction of the media’s capacity and intraparticle mass transport properties under high hydraulic loading rates.