Method for material additive manufacturing of an inorganic filter support from a hot-melt composition and resulting membrane

A method for manufacturing a monolithic inorganic porous support (1) having a porosity comprised between 10% and 60% and an average pore diameter ranging from 0.5 μm to 50 μm, using a 3D printing machine (I) including an extrusion head (6) movably mounted in space relative to and above a fixed horizontal plate (5), said 3D printing machine allowing the deposition of a string (7i,j) of inorganic composition (4) to build, from a 3D digital model (M), a manipulable three-dimensional raw structure (2) intended to form the monolithic inorganic porous support(s) (1), the method consisting of:

• having the inorganic composition (4), said inorganic composition, including a first powdery solid inorganic phase in the form of particles with an average diameter comprised between 0.1 μm and 150 μm, and a second phase in the form of a matrix comprising a hot-melt polymer,
• supplying the extrusion head (6) of the 3D printing machine (I) with the inorganic composition (4), said extrusion head (6) being at a temperature allowing the extrusion of the inorganic composition (4) to form the string (7i,j),
• building, using said string (7i,j) on said horizontal plate (5), the manipulable three-dimensional raw structure (2) in accordance with the 3D digital model (M),
• placing this manipulable three-dimensional raw structure (2) in a heat treatment furnace in order to carry out a sintering operation at a temperature comprised between 0.5 and 1 times the melting temperature of a material forming the powdery solid inorganic phase.