Preparation and regulation of high-strength and high-permeability porous ceramic/PDMS composite membranes for gas-liquid separation

• Porous ceramic/PDMS composite membranes for gas–liquid separation. • It can achieve high methane permeability and robust mechanical property. • Performance of the support layer was optimized by adding SG porogen. • Effects of different porogens on the properties of support layer were analyzed. • Sintering mechanism of porous ceramics containing SG was discussed. Methane detection is crucial in identifying combustible ice within the energy sector. The gas–liquid separation membrane, a key component of methane sensors, plays a critical role in effectively separating methane and water. It significantly enhances the efficiency and stability of detecting methane concentration in situ. However, the related permeability and mechanical property present conflicting requirements in order to achieve optimal membrane performance. This work proposes an investigation into the mass transfer performance of a high-strength composite membrane, utilizing PDMS as the functional layer and porous ceramics as the supporting layer. By adjusting the pore distribution of the porous ceramics, particularly through the use of spherical graphite as a porogen, the study examines the impact of spherical graphite (SG) on the support layer’s morphology and its ability to regulate pore structure. Results indicate that incorporating spherical graphite with a porogen content of 10 wt% and a particle size of 25 μm enhances connections between ceramic grains, resulting in a flexural strength of 56.36 MPa and a permeability coefficient of 1861.57 barrer. This configuration demonstrates good waterproof and breathable performance. Overall, this research presents a novel approach for fabricating methane-water separation membranes, offering valuable insights for underwater methane detection efforts.