Two Birds with One Stone: Copper-Based Adsorbents Used for Photocatalytic Oxidation of Hg (Gas) after Removal of PH.

Cu/TiO adsorbents with CuO as the active component were prepared via a simple impregnation method for efficient purification of phosphine (PH) under the conditions of low temperatures (90 °C) and low oxygen concentration (1%). The PH breakthrough capacity of optimal adsorbent (Cu/TiO) is 136.2 mg(PH)·g, and the excellent dephosphorization performance is mainly attributed to its abundant sur face-active oxygen and alkaline sites, large specific surface area, and strong interaction between CuO and the support TiO. Surprisingly, CuO is converted to CuP after the dephosphorization by Cu/TiO. Since CuP is a P-type semiconductor with high added value, the deactivated adsorbent (CuP/TiO) is an efficient heterostructure photocatalyst for photocatalytic removal of Hg (gas) with the Hg removal performance of 92.64% under visible light. This study provides a feasible strategy for the efficient removal and resource conversion of PH under low-temperature conditions and the alleviation of the environmental risk of secondary pollution.