A filtration membrane comprising cellulose fibres, the membrane having a pore size distribution such that the modal pore diameter is between 10 nm and 25 nm and/or wherein less than 5% of the pore volume comprises pores of greater than 40 nm and having a total porosity greater than 30%.

Provided herein are methods for making a freeze-cast material having a internal structure, the methods comprising steps of: determining the internal structure of the material, the internal structure having a plurality of pores, wherein: each of the plurality of pores has directionality; and the step of determining comprises: selecting a temperature gradient and a freezing front velocity to obtain the determined internal structure based on the selected temperature gradient and the selected freezing front velocity; directionally freezing a liquid formulation to form a frozen solid, the step of directionally freezing comprising: controlling the temperature gradient and the freezing front velocity to match the selected temperature gradient and the selected freezing front velocity during directionally freezing; wherein the liquid formulation comprises at least one solvent and at least one dispersed species; and subliming the at least one solvent out of the frozen solid to form the material.

The present invention relates to a tangential flow separator element for separating a fluid medium for treatment into a filtrate and a retentate, said separator element comprising a monolithic rigid porous support (2) of rectilinear structure with a plurality of channels (3) formed therein for passing a flow of the fluid medium for treatment between an inlet (6) and an outlet (7) for the retentate, in order to recover a filtrate from the outside surface (5) of the support.

According to the invention, the monolithic rigid porous support (2) defines obstacles (9) to the flow of the fluid for treatment, which obstacles extend from the inside walls (31) of said channels, are identical in material and porous texture to the support, and present continuity of material and of porous texture with the support, the obstacles (9) generating variations in the flow sections of the channels.

A ceramic filter 20 has a porous support formed from particles containing a metal oxide as a main component and a membrane layer coated on a surface of the porous support and formed from particles containing the same kind of metal oxide as that of the porous support, wherein the particles forming the membrane layer are loaded with a different kind of metal oxide from that of the particles forming the membrane layer.

Disclosed are a CMS membrane, characterized in that it is obtainable by pyrolysis of a polyimide composed of the monomers 1-(4-aminophenyl)-1,3,3-trimethyl-2H-inden-5-amine and 5-(1,3-dioxo-2-benzofuran-5-carbonyl-2-benzofuran-1,3-dione of the following formulae:

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preferably by pyrolysis of the polyimide having the CAS number 62929-02-6, and a supported CMS membrane comprising a CMS membrane obtainable from a polyimide by pyrolysis and a porous support, characterized in that a mesoporous intermediate layer is provided between the CMS membrane and the porous support.

Further disclosed are a process for preparing the supported membrane, the use of the membranes for separating gas mixtures or liquid mixtures, an apparatus for gas separation or for liquid separation, and the use of the polyimide for preparing a CMS membrane by pyrolysis.

A thin micro-porous membrane sheet and filtering device using it is presented. The membrane sheet includes a thin porous metal sheet of thickness between 20 and 200 μm with a porous ceramic coating of thickness less than 25 μm on at least one of its surfaces. The porous metal sheet has mean pore sizes at micro and sub-micrometer level and has a surface substantially free of pores greater than 10 micrometers. The ceramic coating layer may be made of particles with a mean particle size in a range of 10 to 300 nm and contains certain sintering promoters. The ceramic coating is sintered with the metal sheet in non-oxidizing environment at lower temperatures than typical ceramic membranes. The thin membrane sheet is used to filter fine particulates from micrometers to nanometers from a liquid or gas stream. The thin membrane sheet may be assembled into a filter device having high surface area packing density and straight mini-flow channels.

A method of manufacturing a separator element for obtaining molecular and/or particulate separation by tangential flow of a fluid medium for treatment into a filtrate and a retentate, the element having a structure (2) of at least two porous rigid columns (3) made of the same material, positioned side by side to define, outside their outside walls, a volume (4) for recovering the filtrate, each column (3) presenting, internally, at least one open structure (5) for passing a flow of the fluid medium, opening out in one of the ends of the porous column for inlet of the fluid medium for treatment, and in the other end for outlet of the retentate. The element is a single-piece rigid structure (2) made as a single piece that is uniform and continuous throughout, without any bonds or exogenous additions.

A membrane for fluid species transport includes a porous substrate and a selective-transport layer comprising 2-D-material flakes. The porous substrate defines surface pores with dimensions larger than 2 microns, and the selective-transport layer coats the porous substrate and spans across the surface pores. The porous substrate can be contacted with a liquid or coating to fill or coat the surface pores of the porous substrate. Next, a 2-D-material-flake solution is deposited on the porous substrate. Evaporation of solvent from the deposited 2-D-material-flake solution forms the selective-transport layer.

A method for preparing a graphene composite membrane on the surface of a tubular support. In the method, a tubular ceramic membrane is used as the support, a layer of graphene material is uniformly prepared on the surface of the support by vacuum suction, and the defect-free tubular graphene composite membrane is obtained by the drying process.

Described herein is a crosslinked graphene and biopolymer (e.g. lignin) based composite membrane that provides selective resistance for gases while providing water vapor permeability. Methods for making such membranes, and methods of using the membranes for dehydrating mixtures, are also described.