The disclosure provides an apparatus and method for the separation of a paramagnetic component from a mixture using a mechanical membrane apparatus. The mechanical membrane comprises a supporting material having a plurality of pores where each pore is surrounded by a plurality of magnetic regions. The magnetic regions augment a magnetic field on one side of the supporting material while mitigating the field to near zero on the opposite side. In operation, a flow of fluid such as air comprising a paramagnetic component such as O.sub.2 is directed toward the mechanical membrane, and the paramagnetic component is typically attracted toward a magnetic field surrounding a pore while dimagnetic components such as N.sub.2 are generally repelled. As some portion of the fluid passes through the plurality of magnetic apertures to the opposite side of the mechanical membrane, the mechanical membrane generates a fluid enriched in the paramagnetic component. Alternately, the magnetic field may act to repel the paramagnetic component while diamagnetic components such as N.sub.2 are generally unaffected and pass to the opposite side of the mechanical membrane.

A separation membrane includes a polymer and a plurality of nanoparticles having magnetic properties when placed in an external magnetic field, the relative arrangement of the plurality of nanoparticles determining the selectivity of the separation membrane. A method of fabricating a separation membrane includes intercalating a plurality of nanoparticles with paramagnetic or magnetic ions or molecules to produce intercalated nanoparticles having magnetic properties, depositing a solution of the plurality of intercalated nanoparticles on a support, applying an external magnetic field to the deposited solution of intercalated nanoparticles, and drying the solution of intercalated nanoparticles.

In one aspect, the present invention relates to a membrane material having a first surface, an opposing second surface and a thickness between the first and second surfaces; the membrane material comprising a mineral comprising a metal; and at least one channel between the first surface and the second surface, wherein the channel has a diameter of less than 1 mm.

In one aspect, the present invention relates to a system comprising the membrane material. In one aspect, the present invention relates to a method of purifying a fluid, using said systems and membrane materials.

The present disclosure provides an efficient and stable magnetic nanofiber membrane and a preparation method and use thereof, and belongs to the technical field of composites. The preparation method includes the following steps: dissolving polyacrylonitrile or polystyrene, nZVI particles, and n-octyltrimethylammonium bromide in N,N-dimethylformamide, and mixing uniformly to obtain a spinning solution; subjecting the spinning solution to electrospinning; and vacuum-drying a resulting fiber membrane to obtain the efficient and stable magnetic nanofiber membrane. In the present disclosure, the magnetic nanofiber membrane has a high specific surface area, a desirable porosity, an excellent mechanical strength, and satisfactory magnetic properties. The membrane effectively exerts a synergistic effect of the nZVI particles and an organic polymer material carrier, avoids easy oxidation of a catalyst surface and easy particle agglomeration, enhances a catalytic activity of the magnetic nanofiber membrane, and improves an efficiency in organic wastewater treatment.

A water treatment system for removing contaminant from a feed solution is provided. The system includes a hollow fiber membrane chemical reactor (HF-MCR) and a magnetic field generator; or a magnetic confinement-enabled column reactor (MCCR) comprising one or more column filters and a magnetic field generator. The magnetic field generator is arranged to produce a magnetic field for realizing a magnetically confined zone that results in a formation of a plurality of microwires comprising the zerovalent iron (ZVI) nanoparticles or a plurality of ZVI wires comprising ZVI microparticles. The plurality of microwires can be a magnetic catalyst to enable catalytic degradation and chemical immobilization of the contaminant. The plurality of ZVI wires can reduce aqueous As (As.sub.aq) concentration in the feed solution after the feed solution is pumped through the one or more column filters.

High-quality membranes of complex oxide and complex nitrides are provided. Also provided are method of making the membranes by releasing films of the complex oxides and nitrides from an epitaxial heterostructure using metal islands on the surface of the films as strain-absorbing supports. The methods facilitate the release of flat, large-area membranes characterized by the absence of, or a very low density of, cracks and/or wrinkles. The released membranes are free of the surface organic residues that are present on membranes released with the aid of a polymer support.