modified AC for removing gaseous elemental mercury from flue gas

Area of Science:

• Environmental Science
• Materials Chemistry
• Chemical Engineering

Background:

• Mercury pollution from coal-fired power plants is a significant environmental concern.
• Adsorption technology is a key method for elemental mercury (Hg⁰) removal from flue gas.
• Conventional adsorbents often face challenges with efficiency and stability in flue gas conditions.

Purpose of the Study:

• To synthesize and evaluate a novel copper-iron binary metal sulfide modified activated carbon adsorbent.
• To investigate the mercury removal performance and underlying mechanisms of the synthesized adsorbent.
• To assess the adsorbent's efficiency and stability under simulated flue gas (SFG) conditions.

Main Methods:

• Synthesis of copper-iron binary metal sulfide modified activated carbon.
• Adsorption experiments using simulated flue gas (SFG) at 150 °C.
• Characterization methods to elucidate the mercury removal mechanism.

Main Results:

• The synthesized adsorbent achieved a mercury removal efficiency of 91% under SFG conditions at 150 °C.
• The introduction of iron enhanced the proportion of Cu^IS^I species, facilitating Hg⁰ oxidation.
• Active sulfur sites were generated, promoting Hg⁰ oxidation, with mercuric sulfide (HgS) as the predominant product.

Conclusions:

• Copper-iron binary metal sulfide modified activated carbon exhibits superior mercury removal performance compared to unmodified activated carbon.
• The enhanced performance is attributed to the synergistic effects of copper and iron sulfides, promoting Hg⁰ oxidation.
• The adsorbent demonstrates improved sulfur resistance, making it a viable option for industrial applications.