Development of Nanoscale Hydrated Titanium Oxides Support Anion Exchange Resin for Efficient Phosphate Removal from Water

Abstract

In this work, a macroporous strongly basic anion exchange resin D201 was used as the matrix and loaded with nano hydrated titanium oxide (HTO) to fabricate a novel resin-based nano hydrated titanium oxide adsorbent (HTO-D201), which was characterized by scanning electron microscope-energy dispersion spectroscopy (SEM-EDS), transmission electron microscope (TEM), X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET) analysis. Adsorption isotherm, pH influence competitive adsorption and column adsorption experiments were conducted to investigation the adsorption behavior of HTO-D201 to phosphorus in water. The adsorption effect of adsorbent HTO-D201 on phosphorus in water, and the corresponding adsorption mechanism, are discussed. It was observed that HTO-D201 exhibited spontaneous adsorption behavior with Langmuir fitting maximum adsorption capacity of 34.08 mg∙g−1 under a pH of 6.8 and a temperature of 298 K. Adsorption isotherms confirmed that enhancing temperature could promote the adsorption process. SO42−, NO3− and Cl− were used as competing ions in competitive adsorption, which confirmed better anti-interference ability of HTO-D201 compared with that of unmodified D201. The column adsorption experiment implied that HTO-D201 possessed a stable structure and good dynamic adsorption performance, with effective processing capacity of 420BV, which could be regenerated and recycled. The adsorption mechanism of HTO-D201 to phosphorus in water is discussed, which was ascribed to a quaternary amine group on the resin and a hydroxyl group on the HTO. This work shows that HTO-D201 is a promising adsorbent that a possesses excellent phosphorus-removing capacity from wastewater and the potential for practical application.