Preparation of Wheat Straw Matrix-g-Polyacrylonitrile-Based Adsorbent by SET-LRP and Its Applications for Heavy Metal Ion Removal

Polyacrylonitrile (PAN) was grafted onto the surface of a wheat straw matrix (WSM) by single-electron transfer-living radical polymerization (SET-LRP). A novel agricultural residue adsorbent amidoxime WSM-g-PAN (AO WSM-g-PAN) was obtained by modifying WSM-g-PAN with hydroxylamine hydrochloride (NH2OH·HCl). AO WSM-g-PAN was used to remove heavy metal ions. Compared with WSM, the adsorption capacity of AO WSM-g-PAN for Hg(II) increased greatly, and the maximum adsorption capacity was 4.7 mmol g–1. AO WSM-g-PAN could effectively adsorb Hg(II) from binary ion systems in the existence of Ni(II), Pb(II), Cu(II), Zn(II), and Ag(I).