Removal of Gaseous Elemental Mercury in a Diffusion Electrochemical Reactor Based on a Three-Dimensional Electrode

A novel three dimensional electrochemical reactor with nickel foam and carbon paper used as the anode and stainless steel mesh used as the cathodewas studied in this research. Oxidation mercury removal is performed in a self-made diffusion reactor. The influence of the electrolysis voltage, pH, gas flow, and other factors on mercury removal is discussed, as well as the mechanism of anodization mercury removal is explored. The experimental results show that nickel foam has a significant effect on the removal of Hg⁰, and 80-85% removal can be achieved under optimal conditions. Meanwhile, nickel foam has stable performance at high temperatures (60 °C) and in strong alkaline electrolytes, which also play an effective role in anodized oxidation. Although carbon paper is more stable than nickel foam and less affected by experimental factors, it is sensitive to reaction temperature and can only work in the neutral electrolyte at low temperatures. In contrast, electrochemical catalytic oxidation technology using the nickel foam is more promising for Hg⁰ removal.