Investigation of microwave enhanced catalytic degradation of VOCs with a novel double ridge field compressed cavity

The Effective Flow Coefficient Design Method of Microwave-Assisted Catalytic Reactor for Gas Treatment

“…Based on the model established above, the multiphysics simulation calculation is carried out through COMSOL Multiphysics 6.0. The mathematical equations related to electromagnetic fields, microwave heating, heat conduction, and fluid fields are as follows Electromagnetic fields The microwave field inside the reactor is determined by solving the Helmholtz representation of Maxwell’s equation: , ∇ × ( μ normalr − 1 false( ∇ × bold-italicE false) ) − k 0 2 ( ε normalr j σ ωε 0 ) bold-italicE = 0 where μ r is the relative permeability, E is the complex electric field vector of the time-harmonic oscillating microwave field, k 0 is the wavenumber of vacuum, j is the imaginary unit, ω is the angular frequency of electromagnetic wave oscillation, σ is the electrical conductivity, and ε r is the complex relative permittivity of the medium, consisting of real and imaginary parts ( ε r = ε normalr ′ − j ε normalr ′′ ), where ε normalr ′′ is the dielectric loss factor, which determines the ability of the material to absorb electromagnetic energy and convert it into heat energy. Microwave heating When the microwave acts on the catalyst, the conversion of heat is represented by the following equation: , Q mw = πε 0 ε normalr ′′ f false| bold-italicE false| 2 Heat conduction In this model, the heat transfer in the solid catalyst and the heat transfer between the solid catalyst and the fluid reactants is considered. The energy balance is determined by the following equation: ρ C p ...…”

“…The microwave field inside the reactor is determined by solving the Helmholtz representation of Maxwell’s equation: , ∇ × ( μ normalr − 1 false( ∇ × bold-italicE false) ) − k 0 2 ( ε normalr j σ ωε 0 ) bold-italicE = 0 where μ r is the relative permeability, E is the complex electric field vector of the time-harmonic oscillating microwave field, k 0 is the wavenumber of vacuum, j is the imaginary unit, ω is the angular frequency of electromagnetic wave oscillation, σ is the electrical conductivity, and ε r is the complex relative permittivity of the medium, consisting of real and imaginary parts ( ε r = ε normalr ′ − j ε normalr ′′ ), where ε normalr ′′ is the dielectric loss factor, which determines the ability of the material to absorb electromagnetic energy and convert it into heat energy.…”

“…The mathematical equations related to electromagnetic fields, microwave heating, heat conduction, and fluid fields are as follows 1. Electromagnetic fields The microwave field inside the reactor is determined by solving the Helmholtz representation of Maxwell's equation: 28,34…”

“…Due to the difficulty in controlling this adaptability, the aforementioned promising research is mainly limited to laboratory-scale experiments, and the microwave reactors reported for heterogeneous catalysis are typically small-scale single-mode systems, , with the reaction region volume occupying only a small fraction of the reactor. To address this challenge, our research group has developed a novel double-ridged field compressed cavity (DRFC) reactor, which offers a larger reaction region and higher electric field intensity than previously reported reactors of comparable size. Additionally, some researchers are exploring a new type of traveling wave reactor − that can expand the reaction volume laterally.…”

Analysis of Microwave Effects on the MnO2-Catalyzed Toluene Oxidation Pathway

“…Microwave irradiation, renowned for its efficient heating capabilities, presents a novel approach to catalytic VOC degradation. Differing from traditional heating methods, microwave heating ensures uniform heating throughout the catalyst, minimizing the risk of local temperature spikes that can lead to catalyst deactivation [22]. Additionally, microwave-assisted catalytic oxidation has shown greater efficiency compared to conventional thermal catalytic combustion, mainly due to enhanced mass transfer and reaction kinetics [23].…”