Title : Recent progress for removal of Hg0 and/or NOx with graphene-based catalysts
Abstract:
Graphene or graphene oxide (GO) is an outstanding material that has been commonly applied to modify/assist the catalysts consisting of metal oxides due to its excellent physical and chemical properties. This article reviews recent development on the application of graphene-based catalysts to remove Hg0 and/or NO, the types of graphene application, and the evolution of catalyst preparation methods. The surface characterization analysis was further presented to evaluate the physical and chemical properties and further assess the overall performance of the catalysts. The morphology (2D, 3D, and spherical), heterojunction, and heteroatom doping are expected to have better performance under complex gas conditions. The removal efficiencies of Hg0 and/or NO, the N2 selectivity, the mechanisms of Hg0 and/or NO removal, and the N2O production are thoroughly reviewed. The removal of Hg0 and/or NO can be simulated and described by Eley-Rideal (E-R) and Langmuir-Hinshelwood (L-H) mechanisms to estimate and evaluate the reaction rate and activation energy. The promoting effects on the N2 selectivity of heteroatom doping were further discussed. Furthermore, developing innovative photo- and photothermo-catalysts with high removal efficiency, strong stability, and high resistance are crucial for low-temperature (100-200oC) SCR technology to simultaneously remove Hg0 and NO emitted from coal-fired power plants. This article overviewed graphene-based catalysts including fundamental graphene species, efficient synthesis methods, characterization analysis, the capability of graphene-based materials for the removal of Hg0 and/or NO, and the reaction mechanisms of Hg0 oxidation and NO reduction.
Audience Take Away Notes:
- We provide the recent progress of graphene-based catalysts for Hg0 and/or NOx removal, including the catalyst preparation method, modification for better catalysts in a selective catalytic reduction (SCR), and the advantage brought by graphene, and the reaction mechanisms. This knowledge can help the audience synthesize novel catalysts
- This article could help the audience to conduct the surface characterization, evaluate the physical and chemical properties more efficiently, and understand the potential of using graphene as a modification material, which thus enhance the removal efficiencies of Hg0 and NOx in the flue gases emitted from coal-fired power plants
- This article reviewed and summarized the catalyst preparation methods, the physical and chemical properties of graphene-based catalysts, potential application for simultaneous removal of Hg0 and NOx, and reaction mechanisms, which can be widely applied for their research and teaching works
- Yes, this article provides practical solutions to remove target pollutants, particularly Hg0 and/or NOx, with the existence of poison gases by doping heteroatoms. This will help the engineers and designer’s job more efficient
- This article provides new technical information for developing innovative low-temperature SCR technology for simultaneous removal of Hg0 and/or NOx in the flue gases
- This article will help the environmental scientists and engineers to thoroughly understand the fundamental and practical information on catalysts application to air pollution control
