Ag-Fe3O4@rGO ternary magnetic adsorbent for gaseous elemental mercury removal from coal-fired flue gas.

Abstract Ag nano-particles (NPs) with high dispersion possess the capacity for elemental mercury (Hg0) removal in low temperature. To further enhance its thermo-stability and electron transfer ability, Ag-Fe 3 O 4 @rGO ternary magnetic composite was synthesized for gaseous Hg0 capture. Results indicated that such composite has a Hg0 removal performance with higher than 92% removal efficiency at 100 °C. The ternary composite has a higher Hg0 removal performance than that of pure rGO and Fe 3 O 4 @rGO. The physical-chemical characterization results indicated that Ag nano-particles in-situ grow on the surface of Fe 3 O 4 @rGO support. The large surface area of rGO supply efficient reaction room for Hg and Ag atoms. Ag-Hg amalgam is ascribed to the mercury uptake mechanism. The spent materials can be regenerated by a simple thermal-desorption method. In addition, this magnetic material provide an opportunity that can be separated from fly ashes when used in real flue gas. [ABSTRACT FROM AUTHOR]