Advancing Water Circularity and Decarbonization: A Scalable Electrochemical Pathway for Cyanide-Contaminated Wastewater Treatment

Unofficial AI-generated summary based on the public title and abstract. Not an official translation.

🔬研究者:Provides a novel electrochemical approach for cyanide destruction with low energy consumption and high efficiency, offering a safe alternative to conventional methods.

🏢実務担当者:Can be applied for on-site wastewater treatment to achieve compliance with discharge limits and enable water reuse, reducing operational risks and costs.

🏛政策担当者:May inform regulations on cyanide discharge limits and promote circular water use in industrial operations, aligning with environmental sustainability goals.

Abstract Cyanide bearing wastewater generated from industrial operations, including oil and gas and mining activities, presents significant environmental and occupational risks due to the acute toxicity and volatility of hydrogen cyanide (HCN) under sub alkaline conditions. Conventional treatment methods often rely on chemical oxidation or physical separation processes that either introduce handling risks or fail to achieve complete contaminant destruction at low concentrations. This study evaluates a conductivity enhanced electrochemical oxidation pathway employing an alkaline supporting electrolyte to achieve controlled cyanide destruction under closed loop laboratory conditions. Feed wastewater containing 1.0 mg/L free cyanide and 17,940 mg/L total dissolved solids (TDS) was treated for one hour under controlled alkaline conditions (pH > 9.5) to prevent HCN volatilization. Free cyanide concentrations were quantified using APHA Standard Method 4500-CN− E, with a method detection limit (MDL) of 0.001 mg/L. Electrochemical treatment reduced free cyanide to below the MDL (<0.001 mg/L), corresponding to >99.9% removal efficiency. In contrast, evaporation only testing reduced TDS but retained measurable cyanide (0.025 mg/L), demonstrating that physical separation alone does not eliminate toxicity. The addition of an alkaline supporting electrolyte increased TDS during electro oxidation; however, integration with downstream multi effect evaporation restored water quality by partitioning dissolved solids into a concentrate stream while producing low TDS distillate suitable for industrial reuse. Estimated specific energy consumption (SEC) for the electro-oxidation stage was 2 - 6 kWh/m3, supporting modular scale up and field deployment. The achieved cyanide concentration (<0.001 mg/L) is substantially below commonly applied international discharge thresholds (0.02 - 0.5 mg/L), providing a significant compliance safety margin and enabling water circularity within industrial operations. The results demonstrate that conductivity enhanced electrochemical oxidation offers a safe, scalable, and energy competitive alternative to conventional cyanide treatment approaches.

• crossref https://doi.org/10.2118/232744-msfirst seen 2026-05-18 05:28:23 · last seen 2026-05-31 04:57:49
• semanticscholar https://doi.org/10.2118/232744-msfirst seen 2026-05-23 05:51:53 · last seen 2026-06-16 05:10:12