Covalent organic polymers with azido group for efficient recovery of gold from gold-bearing waste

Abstract

BackgroundGold is a rare precious metal. Efficient and selective adsorption of Au(III) is of great significance for gold recovery. MethodsA covalent organic polymer with azido group (N3-COP) was synthesized utilizing enaminone covalent organic polymer and Ts-N3 as raw materials. Significant FindingsThe adsorption capacity of N3-COP for gold ions was up to 1220 mg·g−1 under the condition that the adsorption process took place at room temperature and at a pH value of 4. The results of adsorption thermodynamic and adsorption kinetic experiments illustrated that the adsorption process of N3-COP for the trivalent gold ion is consistent with the Langmuir adsorption model and Quasi second-order adsorption model. Additionally, this adsorbent has high adsorption selectivity when it is used to adsorb trivalent gold ion from effluent containing gold (III), cadmium (II), nickel (II), cobalt (II), and copper (II) ions. This adsorbent also has good reusability for it maintains excellent adsorption performance after five consecutive adsorption operations.