Membrane absorption has garnered significant attention due to its ability to combine the advantages of membrane separation and chemical absorption methods. During the scale-up of membrane absorption equipment, the fluid flow and mass transfer processes tend to have serious non-ideal effects, arising from the increase in aspect ratio and the number of membrane fibers. However, traditional one-dimensional (1D) and two-dimensional (2D) models are unable to describe the impact of geometry on mass transfer performance. In this study, a three-dimensional (3D) steady-state model is established to simulate the mass transfer process in a multi-fiber membrane contactor using COMSOL Multiphysics software. The 3D steady-state model is proven to be able to accurately predict the CO 2 absorption flux (J CO2 ) under various operating conditions by comparing the simulation results with experimental data. The results indicate a strong correlation between mass transfer performance and fluid velocity distribution. To further explore the flow behavior of gas and liquid at different locations, a 3D dynamic simulation model is developed and compared with experimental data. This model can describe the non-ideal flow behavior and the characteristics of gas and liquid phases in reactors with complex geometries. The results of the 3D dynamic model show that there are priority and slow regions for fluid flow, and CO 2 mass transfer performance can be enhanced by concentrating the membrane fiber arrangement in the priority region. The model developed in this study can be used to evaluate defects in fluid flow patterns, such as channeling, back mixing, and tailing. Furthermore, the 3D steady-state and dynamic models can guide the design of membrane contactors, optimize operating conditions, and provide a reference for analyzing fluid flow morphology and structural optimization in membrane contactors.
Membrane absorption is a convenient and efficient flue SO 2 capture technology . In this study, NH 2 -MIL-125 filled mixed matrix membrane contactor (MMMC) is constructed by Non-solvent Induced Phase Separation (NIPS) method. The functional groups and metal active sites on the surface of NH 2 -MIL-125(Ti) exhibit high affinity for SO 2 . The microporous structure of NH 2 -MIL-125(Ti) provides storage for adsorbed SO 2 , which is conducive to the formation of SO 2 enrichment zone in the membrane. The membrane morphology, wetting resistance, and light responsiveness et al of MMMC have been tested. The combination of NH 2 -MIL-125(Ti) adsorption and membrane absorption process effectively promotes the transfer of gas molecules in the membrane pores. The SO 2 absorption flux of MMMC filled by NH 2 -MIL-125(Ti) has a significant increment, reaching 8.81 × 10 −4 mol·m −2 ·s −1 and 9.77 × 10 −4 mol·m −2 ·s −1 under non-light and visible light conditions respectively, which is comparability with results in literature. The membrane phase mass transfer coefficient calculated by Wilson model is 149.6 s·m −1 , which shows the low resistance in membrane. The SO 2 absorption flux keep stable after 4 cycles of tests. The membrane contactor coupled with function fillers enhances the SO 2 capture ability and further promotes the enrichment of SO 2 , which has favorable development foreground.
The nanodrug delivery system-based nasal spray (NDDS-NS) can bypass the blood–brain barrier and deliver drugs directly to the brain, offering unparalleled advantages in the treatment of central nervous system (CNS) diseases. However, the current design of NNDS-NS is excessively focused on mucosal absorption while neglecting the impact of nasal deposition on nose-to-brain drug delivery, resulting in an unsatisfactory nose-to-brain delivery efficiency. In this study, the effect of the dispersion medium viscosity on nasal drug deposition and nose-to-brain delivery in NDDS-NS was elucidated. The optimized formulation F5 (39.36 mPa·s) demonstrated significantly higher olfactory deposition fraction (ODF) of 23.58%, and a strong correlation between ODF and intracerebral drug delivery (R2 = 0.7755) was observed. Building upon this understanding, a borneol-modified lipid nanoparticle nasal spray (BLNP-NS) that combined both nasal deposition and mucosal absorption was designed for efficient nose-to-brain delivery. BLNP-NS exhibited an accelerated onset of action and enhanced brain targeting efficiency, which could be attributed to borneol modification facilitating the opening of tight junction channels. Furthermore, BLNP-NS showed superiority in a chronic migraine rat model. It not only provided rapid relief of migraine symptoms but also reversed neuroinflammation-induced hyperalgesia. The results revealed that borneol modification could induce the polarization of microglia, regulate the neuroinflammatory microenvironment, and repair the neuronal damage caused by neuroinflammation. This study highlights the impact of dispersion medium viscosity on the nose-to-brain delivery process of NDDS-NS and serves as a bridge between the formulation development and clinical transformation of NDDS-NS for the treatment of CNS diseases.
危险品化学品经营许可证（带存储）