▎ 摘　　要

Graphene oxide has great potential for use as an adsorbent due to the high specific surface area, high negative charges, and abundant oxygen-containing functional groups. However, the difficulty of graphene oxide to separate from water renders it impractical for real water treatment. In the present study, a novel graphene oxide/hexadecyltrimethylammonium composite sponge (GO/HDTMA) was prepared and investigated for use as a filtration material for the removal of Cu(II) from water. The formed porous GO/HDTMA sponge was highly stable in water. The adsorption was spontaneous and exothermic, increasing with decreasing temperatures. The material showed good ability to remove Cu(II) with competing cations (K+, Na+, Ca2+, and Mg2+) present. Five cycles of adsorption-desorption-regeneration studies showed that, after adsorption, the material could be successfully regenerated for repeated use by using a 1-M HCl solution as the desorption reagent. At a sufficiently high dose, GO/HDTMA showed an excellent performance for Cu(II) removal from river water containing different coexisting solutes. Finally, our 30-day column study revealed that the GO/HDTMA sponge is a good filtering material for the removal of Cu(II) from river water. In conclusion, the GO/HDTMA sponge is an excellent adsorbent material for use in flow-through water treatment applications for Cu(II) removal.