Highly Efficient Adsorption of Au(III) from Water by a Novel Metal-Organic Framework Constructed with Sulfur-Containing Ligands and Zn(II)

Recovery of precious metal ions from wastewater can bring huge economic benefits and alleviate current supply shortage in industries. Here, a novel metal-organic framework (2,5-TP) constructed with sulfur-containing ligands and Zn(II) was synthesized as a highly efficient adsorbent to adsorb Au(III) from water for the first time. Compared with that of the reported adsorbents, 2,5-TP exhibits excellent Au(III) adsorption performance with the maximum adsorption capacity of 1253.5 mg.g(-1) and an adsorption ratio of 97%. Significantly, 2,5-TP has excellent selectivity toward Au(III) and remarkable recycle performance. The adsorption kinetics for Au(III) adsorption can be described well by the pseudo-second-order kinetics and the adsorption isotherm data accord well with the Sips model, indicating that the adsorption of Au(III) onto 2,5-TP is a heterogeneous chemisorption process. The formation of Au-S and Zn-O-Au bonds suggests an important role in Au(III) adsorption. With the facile synthesis, high adsorption capacity, excellent selectivity, and outstanding reusability, the 2,5-TP adsorbent could be a promising candidate to adsorb Au(III) from water.