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The upscaling process of multicomponent mass transfer and reaction in a rigid and homogeneous porous media was carried out using the method of volume averaging. The first-order reversible reaction which occurs at the solid-fluid interface was considered in this paper. The corresponding macroscopic governing equations were derived from the system dynamics at the pore scale. The effective coefficients were obtained by solving the associated closure problems. This study shows that if the backward reaction rate constant at the microscale is small enough, i.e. k - → 0 , the obtained upscaled model is in accordance with the macroscopic model derived from the first-order irreversible heterogeneous reaction case which was extensively investigated in the literature. The influence of reaction rates on the effective parameters in the macroscopic equations was also investigated. It has been found that both forward and backward reaction rates have significant influence on the effective diffusivities and effective reaction rates in the macroscopic equations. The established equations were successfully verified by the comparison of the direct numerical calculations. [ABSTRACT FROM AUTHOR]

• The rise of alkyl chain length led to different trend of mass transfer enhancement. • Biggest mass transfer enhancement by 36.8% was obtained under the C4H9 alkyl chain. • Interfacial mass transfer enhancement mechanisms by JNPs were elucidated. • Solute diffusion behaviors and molecule interaction energy are main mechanisms. Janus nanoparticles (JNPs) have drawn significant attention due to their unique surfaces with dual character. Herein, molecular dynamics simulation was conducted to investigate the molecular transfer characteristics across the hexane/water interface with amphiphilic JNPs, to elucidate the interfacial mass transfer enhancement mechanisms. The results manifested that the enhancement by JNPs first increases and then decreases with the rise of alkyl chain length, which is up to the biggest improvement under the C 4 H 9 alkyl chain (JNPs-4). The enhancement can be ascribed to the competitive balance between solute diffusion behaviors and molecule interaction energy. The self-diffusion coefficient of solute and the interaction between the solute and oil phases decreases, while the interaction between the solute and water phases increases with the rise of alky chain length. Moreover, maximum enhancement can be obtained by 5 vol% concentration JNPs-4 with 13.4 Å particle diameter, in which the mass transfer resistance is reduced by 36.8%. [ABSTRACT FROM AUTHOR]

• Vapor-liquid mass transfer layer performance was studied by the tracer method. • Mass transfer coefficients that consider four structure parameters were obtained. • The correlations of mass transfer coefficients exhibit good universality. • The correlations were used for the structure optimization of mass transfer layer. In order to implement the multi-scale model to optimize the structure of vapor-liquid mass transfer layer, vapor and liquid mass transfer coefficients that embrace the effects of structure parameters of mass transfer layer should be obtained in advance. In the study, the influences of four structure parameters on mass transfer performance were studied by the tracer method. Moreover, the corresponding mass transfer coefficients were correlated. By comparing with the experimental data of different types of structured catalytic packings, it has been found that the correlations exhibit good universality. Furthermore, the correlations were applied to the non-equilibrium model for the hydrolysis of methyl acetate (MA), so as to investigate the influences of four structure parameters on catalytic distillation process. The results indicated that wavy height and the area ratio of mass transfer layer to catalyst layer have more significant influences on the conversion of MA than inclined angle and base length. [ABSTRACT FROM AUTHOR]