Facile and Eco-Friendly Fabrication of Multifunctional Melamine Sponge for Labeled Cr(VI) Removal and Highly Efficient Oil/Water Separation

Fabrication of multifunctional adsorbent of single-phase material is quite challenging and meaningful for water treatment. In this work, a polyaminosiloxane functionalized melamine sponge is used to remove both heavy metal ions and oil from water. Benefiting from its porous structure, superhydrophobic surface, and abundant amino groups on the surface, the sponge shows excellent performance in Cr(VI) removal and oil/water separation. Notably, the sponge exhibits fluorescent detection function for Cr(VI) owing to the packing of Schiff-base bonds, facilitating the adsorption process to be monitored in real time. The maximum adsorption capacity of Cr(VI) is 252.82 mg g(-1) with good selectivity. In addition to the excellent Cr(VI) removal performance, its superhydrophobic nature allows it to adsorb 92.42 times the weight of oil and realize 99.97% oil/water separation efficiency. This trifunctional cost-effective adsorption material shows great potential for large-scale water purification application.