Activation of Periodate by Freezing for the Degradation of Aqueous Organic Pollutants

A new strategy (i.e., freezing) for the activation of IO 4 – for the degradation of aqueous organic pollutants was developed and investigated. Although the degradation of furfuryl alcohol (FFA) by IO 4 – was negligible in water at 25 °C, it proceeded rapidly during freezing at −20 °C. The rapid degradation of FFA during freezing should be ascribed to the freeze concentration effect that provides a favorable site (i.e., liquid brine) for the proton-coupled degradation process by concentrating IO 4 –, FFA, and protons. The maximum absorption wavelength of cresol red (CR) was changed from 434 nm (monoprotonated CR) to 518 nm (diprotonated CR) after freezing, which confirms that the pH of the aqueous IO 4 – solution decreases by freezing. The degradation experiments with varying experimental parameters demonstrate that the degradation rate increases with increasing IO 4 – concentration and d…