Hydrothermally robust carbon-silica-zirconia ceramic membranes for efficient pervaporation dehydration

Silica-derived membranes offer significant potential for pervaporation (PV) dehydration applications due to their distinct sieving properties and tunable chemical structures. However, simultaneously enhancing hydrothermal stability, hydrophilicity, and porosity remains a formidable challenge. In this study, carbon-SiO 2 -ZrO 2 ceramic composite membranes were fabricated by calcining organic chelating ligand-modified SiO 2 -ZrO 2 (APTES-ZrTB-GA, AZG) precursors under an inert atmosphere. The AZG-550 membrane, carbonized at 550 °C, exhibits an optimal balance of high microporosity and moderate hydrophilicity, resulting in outstanding PV dehydration performance governed by both adsorption-diffusion and molecular sieving mechanisms. During the PV dehydration of H 2 O/MeOH (10/90 wt. %) and H 2 O/EtOH (10/90 wt. %), the membrane achieved H 2 O permeances exceeding 10 -6 mol m -2 s -1 Pa -1 , with H 2 O/MeOH and H 2 O/EtOH selectivities of 140 and 2000, respectively. Moreover, the free carbon derived from the calcination process played a crucial role in preserving the integrity of the SiO 2 -ZrO 2 network, thereby significantly enhancing the hydrothermal stability of the membrane. This study provides important insights into the design of high-performance silica-derived membranes for PV dehydration, emphasizing the potential of carbon incorporation to improve both stability and membrane performance. • Hydrothermal robust C-SiO 2 -ZrO 2 membranes are fabricated for PV dehydration • Carbonization ensures thermal stability, membrane hydrophilicity, and microporosity • Combination of hydrophilicity and loose structure drives superior PV performance • Free carbon ensures structural hydrothermal stability of C-SiO 2 -ZrO 2