This document presents the research activities related to the development of membrane technologies for high-temperature oxygen separation to be integrated into industrial processes, with the aim of reducing energy consumption and production costs of this gas in high-temperature industrial processes. Specifically, the results of experimental activities conducted for the fabrication, optimization, and characterization of ceramic membranes for oxygen separation are reported. Planar asymmetric membranes (diameter ~ 15 mm), produced using the sequential tape casting technique, were tested at high temperatures (700 – 1020°C) in both air and pure oxygen. The test results highlighted excellent performance in terms of permeation, layer density, and stability during thermal cycles. These results were also confirmed by microstructural characterization performed on the samples after testing.

The manufacturing activity focused on scaling up the membrane samples, starting with the optimization of the deposition process through tape casting to produce samples with a large area and uniform thickness. Subsequently, tests were carried out on cutting porous layers to create the necessary interlayers that would give the membrane sample a channel structure and feed the sweep gas. These were then laminated with the asymmetric membranes. The laminated samples were subsequently sintered at high temperatures, resulting in multilayer planar membrane structures (semi-cells) free from defects.

For the membrane module assembly, it is necessary to have a sealing system for the ceramic samples that ensures the closure of all lateral porosities of the support. To this end, ceramic pastes were developed, applied to the lateral surface of the samples, and then thermally treated. Subsequent characterization showed that sufficient density was achieved for both sealing and assembly paste purposes. Additionally, initial tests were conducted to join ceramic membranes with metal samples from the module, using a glass-ceramic sealant.

Finally, based on the results of permeation tests conducted in the laboratory on asymmetric ceramic membrane samples, a numerical model was developed to describe the fluid dynamic behavior of the membrane module. This model will be used to optimize its operation and efficiency in preparation for the next detailed design phase.