3D-printed ceramic membranes: Fabrication and hydrogen permeation performance
Andrea Bartoletti, Elisa Mercadelli, V. Saraceni, Alex Sangiorgi, Angela Gondolini, Cesare Melandri, Paola Pinasco, Pio Gramazio, Andrea Fasolini, Jacopo De Maron, Francesco Basile, Alessandra Sanson
Abstract
: In this work, the possibility of using 3D printing technology as a tool to boost the widespread use of all-ceramic membranes operating at high temperatures for hydrogen separation and membrane reactors is proposed for the first time. Dense ceramic-ceramic composite membranes based on BaCe 0.65 Zr 0.20 Y 0.15 O 3-δ -Gd 0.2 Ce 0.8 O 2-δ were produced by 3D microextrusion. A suitable water-based ink was formulated and thermally/rheologically characterized. Both printing parameters and post-printing operations were carefully adjusted to obtain crack-free and planar membranes. In particular, the use of polyethylene glycol with the lowest molecular weight as desiccant liquid combined with a warm ethanol washing bath is crucial for the production of defect-free microextruded ceramics. The optimization of the whole ceramic process allows the fabrication of ceramic membranes with a relative density of 98.7 ± 1.1 % and a flexural strength of 98.4 ± 18.9 MPa. After activation with Pt nanoparticles, the 3D microextruded membranes show H 2 permeabilities of 0.21 and 0.32 mL min -1 cm -2 at 750 °C using a feed stream with respectively 50 % and 80 % of H 2 in He. These hydrogen fluxes are among the highest reported so far for symmetric all-ceramic membranes.