Efficient organic iodide capture by a mesoporous bimetallic-organic framework

Release of radioactive organic iodide into atmosphere without any treatment will seriously endanger the environment and life safety. However, removal of radioactive organic iodides is challenging due to their extremely low concentration combined with harsh operational conditions such as high humidity and acidic conditions. Here, we report the generation of mesopores from a metal-organic framework, enabling a record adsorption of >2.8 g/g at room temperature and >0.87 g/g at 423 K toward CH3I under dynamic conditions as demonstrated by breakthrough experiments. Even under humid and acidic conditions, its adsorption performance is maintained. The complete removal of CH3I (expressed by retention time) using this material under humid and acidic conditions is as long as 100 min/g, suggesting its potential application in sequestrating radioactive organic iodide. The excellent adsorption performance is mainly due to (1) physical adsorption and (2) the methylation reaction between pyrazole-4-carboxylic acid and CH3I.