The CO₂ capture technology using a membrane contactor is a hybrid approach that combines the advantages of traditional chemical absorption (high CO₂ selectivity) with those of separation membranes (compactness). Compared to conventional packed towers, membrane contactors can reduce their volume by up to one-tenth by dramatically increasing the specific surface area between gas and liquid. Additionally, because they use hollow fiber membranes made of polymeric material, the process volume is small and lightweight. The modular nature of membrane contactors also allows for easy scale-up, making them a suitable alternative to existing packed tower technology when CO₂ capture is needed in confined spaces.

Despite these many advantages, a significant obstacle to commercialization is membrane wetting, a phenomenon that reduces membrane performance. In the membrane contactor, CO₂ is transferred by diffusion and separated by reactivity with the absorbent. When membrane wetting occurs, the mass transfer resistance within the pores increases significantly, resulting in a decrease in CO₂ absorption performance. To solve this problem, the most effective methods involve increasing the surface tension of the absorbent or enhancing the hydrophobicity of the membrane itself.

In this study, a membrane contactor was fabricated using polyvinylidene fluoride (PVDF), a fluorine-based polymer with excellent hydrophobicity, and CO₂ absorption experiments were then conducted. When modularizing the hollow fiber membranes produced with an optimized recipe, the packing density and specific surface area were calculated based on the number of hollow fiber membranes. These calculated values were then compared with experimental results to confirm the CO₂ absorption performance under various conditions. In the future, we aim to confirm the possibility of scale-up by discussing performance optimization plans, including the design of hollow fiber membrane packaging under controlled spinning conditions and during modularization.

Keywords: Carbon Dioxide; Carbon Capture; Hollow Fiber Membrane; Membrane Contactor; Membrane Wetting

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