Durable, porous alumina-carbon nanotube membranes and methods for making them using spark plasma sintering. Methods for removing heavy metals such as cadmium from waste water using alumina-carbon nanotube membranes.

The present invention discloses a FeAl-based metal porous membrane and a preparation method thereof, which relate to the technical field of industrial gas-solid and liquid-solid separation and purification, and mainly address problems in the prior art, such as cracking-prone and peeling of a membrane layer of an existing FeAl-based metal porous membrane during its preparation and use. The preparation method of the present invention comprises the steps of: adding a FeAl-based metal powder and a metal fiber powder into an organic-additive-added water-based solvent, and mixing them into a slurry; casting the slurry, through a casting machine, to form a membrane green body on a metal substrate layer, and letting it dry; and placing the dried membrane green body in a sintering furnace, to remove organic substances and perform high-temperature sintering and predetermined-temperature reaction synthesis.

The invention relates to a multilayer metallic or ceramic membrane device, comprising a macroporous carrier layer including pores having a pore diameter of more than 50 nm, and at least one mesoporous intermediate layer disposed thereon, including pores having a pore diameter of 2 nm to 50 nm. The membrane device according to the invention furthermore comprises at least one microporous cover layer disposed on the mesoporous intermediate layer, including pores having an average pore diameter of 0.3 nm to 1.5 nm, comprising graphite oxide or few-layer graphene oxide or graphite or few-layer graphene. In an advantageous embodiment, the cover layer comprises between 5 and 1000 layers of graphene oxide. In an advantageous embodiment, the cover layer can comprise between 5 and 1000 layers of partially reduced graphene oxide or graphene as a result of the at least partial reduction of the graphene oxide. The multilayer, chemically and mechanically stable and temperature-resistant membrane device according to the invention, comprising the functional cover layer thereof including microporous graphene oxide or graphene, is advantageously suitable for use in water separation or purification, or for gas separation.

A universal, scalable, solvent-free, one-step method for thermal annealing a stainless steel membrane to create a superhydrophilic surface. The superhydrophilic membrane itself, and methods for using it to separate oil and water in an oil and water mixture or for photocatalytic degradation of methylene blue and other organic contaminants.

Described are porous sintered metal membranes that include multiple layers made from different metal particles, that may be useful as filter membranes, and methods of making and using the porous sintered metal membranes.

The present invention relates to a membrane and a method for manufacturing a membrane for filtering a fluid, said membrane comprising: a substrate having a three-dimensional structure and consisting of an one-piece ceramic porous body; and at least one separating filtering layer having a porosity that is lower than that of the substrate, in which the three-dimensional structure of the substrate is produced by forming elemental layers that are stacked and connected in series with one another, by repeating steps: a) depositing a continuous bed of powder at least partially consisting of a powder intended for forming the ceramic porous body; b) locally consolidating, part of the deposited material such as to create the elemental layer, and simultaneously linking the elemental layer thus formed with the preceding layer such as to gradually grow the desired three-dimensional shape.

A process for making an iron oxide impregnated carbon nanotube membrane. In this template-free and binder-free process, iron oxide nanoparticles are homogeneously dispersed onto the surface of carbon nanotubes by wet impregnation. The amount of iron oxide nanoparticles loaded on the carbon nanotubes range from 0.25-80% by weight per total weight of the doped carbon nanotubes. The iron oxide doped carbon nanotubes are then pressed to form a carbon nanotube disc which is then sintered at high temperatures to form a mixed matrix membrane of iron oxide nanoparticles homogeneously dispersed across a carbon nanotube matrix. Methods of characterizing porosity, hydrophilicity and fouling potential of the carbon nanotube membrane are also described.

A method of making a ceramic honeycomb article which includes: applying at least one green membrane coating layer on a green substrate, the green substrate comprising a plurality of cells comprised of a plurality of interior channels and a plurality of porous interior walls between the channels; drying the at least one green membrane coating layer on the green substrate to produce a green coated substrate; and firing the green coated substrate into a porous substrate, wherein applying the at least one green membrane coating layer and the drying the at least one green membrane coating layer are repeated from 2 to 10 times prior to firing to form multiple green membrane coating layers on the green substrate and wherein the firing the green coated substrate forms a ceramic honeycomb article comprised of the porous substrate and multiple fired coating layers on the porous substrate.

Zeolite membrane sheets for separation of mixtures containing water are provided, as well as methods for making the same. Thin, but robust, zeolite membrane sheets having an inter-grown zeolite crystal film directly on a thin, less than 200 micron thick, porous support sheet free of any surface pores with a size above 10 microns. The zeolite membrane film thickness is less than about 10 microns above the support surface and less than about 5 microns below the support surface. Methods of preparing the membrane are disclosed which include coating of the support sheet surface with a seed coating solution containing the parent zeolite crystals with mean particle sizes from about 0.5 to 2.0 microns at loading of 0.05-0.5 mg/cm2 and subsequent growth of the seeded sheet in a growth reactor loaded with a growth solution over a temperature range of about 45 C. to about 120 C.

A process for making an iron oxide impregnated carbon nanotube membrane. In this template-free and binder-free process, iron oxide nanoparticles are homogeneously dispersed onto the surface of carbon nanotubes by wet impregnation. The amount of iron oxide nanoparticles loaded on the carbon nanotubes range from 0.25-80% by weight per total weight of the doped carbon nanotubes. The iron oxide doped carbon nanotubes are then pressed to form a carbon nanotube disc which is then sintered at high temperatures to form a mixed matrix membrane of iron oxide nanoparticles homogeneously dispersed across a carbon nanotube matrix. Methods of characterizing porosity, hydrophilicity and fouling potential of the carbon nanotube membrane are also described.