Constructing a solar-driven capture material for iodide removal from aquatic radio waste

Abstract

Radioactive elements have recently received much attention considering that it does serious harm to the human and environment. The solar-driven adsorption coupled interface evaporation process is a more efficient method for treating volatile radioactive iodide ions. Herein, a newly induced capture strategy was designed to obtain efficient solar-driven adsorption coupled interface evaporation material for high performance treatment of iodide ions via skillfully molecular design and pore size regulate process, in which 1,3-dichloroisoquinoline with smaller block structures serving as the trapper. In addition, the unique π-π interactions of conjugated microporous polymers (CMPs), as well as the excellent water transport channel penetrated by hydrogel, contribute to the capture of target ions. In this paper, the hollow microspheres CMPs-1 exhibited the highest iodide adsorption capacity (15.96 mg g⁻¹), reaching equilibrium after 7 h of static adsorption in a 0.10 mmol L^-1 iodide ions solution. Under 1 sun, CMP-based porous composite hydrogel PCH-CMP-1 realized outstanding pure water interfacial evaporation rate (2.42 kg m⁻²h⁻¹), which exceeded the evaporation rate reported in many other literatures. Based on the iodine adsorption capacity of CMPs-1 and the excellent interfacial evaporation ability of PCH-CMP-1, PCH-CMP-1 had a good interfacial evaporation rate for iodide ions solutions (1.50 kg m⁻²h⁻¹), and the distillate did not contain iodide ions, in which some are adsorbed by the PCH-CMP-1 and some remain in the solution. With its extraordinary pore structure and excellent interfacial evaporation ability, the PCH-CMP-1 demonstrates the potential of an excellent solar-driven adsorption coupled interface evaporation materials for treating radioactive iodine.