Related Experiment Video
Updated: Jan 18, 2026

Inactivation of Pathogens via Visible-Light Photolysis of Riboflavin-5′-Phosphate
Published on: April 6, 2022
Alkaline UV/PAA synergistic degradation of iron-cyanide complexes: UV-driven ligand disruption and radical oxidation
Yuanna Zhou1, Siqi Zhu1, Zhun Yan1
1Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing, 400045, PR China.
Abstract:
The advanced degradation of ferricyanide ([Fe(CN)₆]³⁻) in industrial wastewater faces dual bottlenecks of self-acidification-induced hydrogen cyanide (HCN) release and inefficient decomplexation. This study innovatively constructs an alkaline UV/Peracetic Acid (PAA) synergistic system and systematically elucidates its triple action mechanism: (1) UV irradiation at 254 nm directly drives ligand-to-metal charge transfer (LMCT) excitation of ferricyanide, achieving efficient Fe-CN bond breaking (Φ₂₅₄ = 0.235-0.267 mol·Einstein⁻¹); (2) hydroxyl radicals (•OH) and organic radicals from PAA photolysis dominate the deep oxidation of free cyanide (contribution rate > 90 %); (3) The alkaline UV/PAA system possesses a self-stabilization mechanism: the oxide radical ion (O•⁻) derived from photolysis of deprotonated PAA and H₂O₂ release alkalinity during their conversion to •OH, neutralizing the acidification effect caused by ferricyanide decomplexation and maintaining pH fluctuations < 0.17 units. Addressing the kinetic mismatch between ferricyanide decomplexation and PAA pyrolysis (where kPAA/k[Fe(CN)₆]³⁻ ranges from 14.95 to 1.56), a delayed addition strategy is proposed: UV irradiation of ferricyanide is performed first, followed by PAA introduction. This strategy reduces total cyanide in actual wastewater to < 0.004 mg·L⁻¹, while shortening total treatment time by 50 % and avoiding HCN risk. This research provides a sustainable solution for safe treatment of cyanide-containing wastewaters with reduced chemical consumption and enhanced process stability.
More Related Videos
08:30A Complete Method for Evaluating the Performance of Photocatalysts for the Degradation of Antibiotics in Environmental Remediation
Published on: October 6, 2022
11:20An Integrated System to Remotely Trigger Intracellular Signal Transduction by Upconversion Nanoparticle-mediated Kinase Photoactivation
Published on: August 30, 2017
Related Concept Videos
Radical Autoxidation
EDTA: Auxiliary Complexing Reagents
The Electron Transport Chain
Inhibitors of the electron transport chain
Rotenone, a widely used pesticide, prevents electron transfer from Fe-S cluster to ubiquinone or Q...
Extraction: Advanced Methods
Alkynes to Carboxylic Acids: Oxidative Cleavage
Radical Oxidation of Allylic and Benzylic Alcohols