A novel method has been developed for the concurrent treatment of Cr(VI)-contaminated wastewater and the production of useful I2 chemical. This innovative technique relies on a redox reaction between Cr(VI) and I– that occurs when freezing an aqueous solution containing these components. The freeze concentration effect, which accumulates Cr(VI), I–, and protons in the ice grain boundaries, drives this reaction. Confocal Raman spectroscopy confirmed this effect, alongside experiments varying I– concentration and pH. Complete Cr(VI) reduction (20 μM) was achieved under freezing conditions with I– concentrations ≥ 100 μM, pH ≤ 3.0, and temperatures ≤ −10°C. The cooling method (liquid vs air) impacted the reduction rate but not the final efficiency. Tested on electroplating wastewater, simultaneous Cr(VI) reduction and I2 production were efficient in frozen solutions but absent in liquid. Other wastewater substances did not hinder the process, making this freezing/Cr(VI)/I– system a promising water-energy nexus technology.-Scientific Journal cover design by scapiens
[Scientific Journal cover design] Low-Thermal-Budget Fluorite-Structure Ferroelectrics for Future Electronic Device Applications
In article number 2100028, Jiyoung Kim, Si Joon Kim, and their team review key factors involved in developing fluorite-structure ferroelectrics
