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 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 including an extrusion head movably mounted in space relative to and above a fixed horizontal plate, said 3D printing machine allowing the deposition of a string of inorganic composition to build, from a 3D digital model, a manipulable three-dimensional green structure intended to form the monolithic inorganic porous support, the method consisting of:

• having the inorganic composition, 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 of the 3D printing machine with the inorganic composition, said extrusion head being at a temperature allowing the extrusion of the inorganic composition to form the string,
• building, using said string on said horizontal plate, the manipulable three-dimensional green structure in accordance with the 3D digital model,
• placing this manipulable three-dimensional green structure 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.