Hydrophobic modification of Al₂O₃ ceramic membranes and application to CO₂ desorption from carbon-rich amine solvents

In the process of engineering the application of membrane reactors, membrane wetting remains a concern for people to hinder the efficient application of membrane reactors. When membrane wetting occurs, the liquid-phase solvent penetrates the pore structure of the membrane, destroying the original stable gas-liquid interface. This brings about a lower mass transfer capacity of the membrane and may trigger chain reactions like membrane fouling to weaken the stability of the membrane separation, amplify economic expenditures of the system, and severely restrict the large-scale promotion and application of membrane technology in chemical engineering, energy, environmental protection, and other fields. As the most commonly used and effective strategy to inhibit membrane wetting, hydrophobic modification of membranes has become a research hotspot and core direction in the field of membrane technology. Its core technical principle is to significantly increase the contact angle formed in the interspace of the membrane surface and the liquid through specific surface modification methods, thereby constructing an effective hydrophobic barrier to fundamentally inhibit the occurrence of membrane wetting. With the advantages of high operational feasibility and remarkable modification effect, this method stands out among many membrane modification technologies and has attracted widespread attention. Based on the above research background, this study selects two excellent hydrophobic modifiers, 1H,1H,2H,2H-perfluorodecyltriethoxysilane (FC16) and hexadecyltriethoxysilane (C16), to carry out a systematic hydrophobic modification study on ceramic membranes. During the experiment, the performance of multiple variables was evaluated and compared before and after the hydrophobic modification in terms of surface properties, micro-morphology, and mass transfer performance of ceramic membranes based on various characterization methods including water contact angle (WCA) measurement, scanning electron microscope (SEM) observation, and N 2 mass transfer flux test. In addition, to better fit the actual application scenarios, the application potential of hydrophobic modified ceramic membranes in the CO 2 membrane desorption process is further explored. Today, the specially built membrane-based desorption device is recognized as an interesting tool for assessing the mass transfer of modified ceramic membranes in the MEA solution system. In this way, a good understanding of strong theoretical and practical foundations, development, and optimization of high-performance membranes will be offered.