Preparation of magnetic biosorbents based on cypress wood that was pretreated by heating or TiO2 deposition

Abstract

The main objective of this work was to prepare magnetic adsorbents based on cypress wood (CW) that was pretreated by heating (HCW) or by deposition of TiO2 (TiO2-CW). Three magnetic adsorbents were prepared: magnetic cypress wood (MCW), magnetic heat-treated cypress wood (MHCW) and magnetic titanium dioxide treated cypress wood (M-TiO2-CW). These were then used for adsorption and magnetic solid phase extraction (MSPE) of Co(II), Cu(II) and Zn(II). The adsorbents were characterized by FT-IR, XRD, BET, elemental analysis and pHpzc. Adsorption studies showed that CW can be used for extraction of Cu(II) and Zn(II) at pH10.6; TiO2-CW can be used for extraction of Cu(II) and Zn(II) at either pH 9.2 or 10.6; while HCW can be used for extraction of all the investigated metals at pH10.6. After magnetization of the adsorbents, it was found that at pH 9.2 any of the magnetic adsorbents can be used for extraction of all the investigated metals. Three MSPE procedures (using the three magnetic adsorbents at pH 9.2) were optimized and applied on real water samples.