A polyolefin fiber that is formed by a thermoplastic composition containing a continuous phase that includes a polyolefin matrix polymer and nanoinclusion additive is provided. The nanoinclusion additive is dispersed within the continuous phase as discrete nano-scale phase domains. When drawn, the nano-scale phase domains are able to interact with the matrix in a unique manner to create a network of nanopores.

A hollow fiber membrane including a dense layer at least on an inner surface side of the hollow fiber membrane, in which when the inner surface of the hollow fiber membrane is observed under an atomic force microscope, a plurality of groove-like recesses oriented in a lengthwise direction of the hollow fiber membrane are observed, an aspect ratio defined as a ratio of a length to a width of each of the recesses is greater than or equal to 3 and less than or equal to 30, a yield strength of the hollow fiber membrane in a dry state is greater than or equal to 30 g/filament, and a breaking elongation is less than or equal to 20%/filament.

A method is disclosed for forming a microporous membrane that incorporates an additive having low water solubility at the membrane's active surface from a precipitation fluid. The incorporated additive at the membrane's active surface can improve one or more of the membrane's hydrophilicity, wettability, anti-fouling behavior, blood compatibility, and stability over long periods of use or repetitive use. The microporous membrane with this modified active surface can be a hollow fiber, flat sheet, or other self-supporting shape. The microporous membranes can be used for membrane filtering or a solute and/or solvent exchange process, which involve contacting aqueous-based fluid or blood with the microporous membrane, such processes for dialysis, blood oxygenation, or blood separation filtering, or other processes.

The present invention deals with a method for obtaining membranes in the form of hollow fibers with application in the field of carbon dioxide removal from natural gas. The aforementioned membranes are obtained by means of heat treatment of polymeric membranes. In this method, polymeric membranes are obtained by a phase-inversion technique by immersion-precipitation and are subsequently subjected to a heat treatment, that is, that the membranes effectively become precursor membranes of the heat treatment. The heat treatment process involves the optimization of the heating rate, temperature, and stabilization time variables, aiming at the improvement of the transport properties of the polymeric membranes. After the heat treatment, it becomes possible to use the membranes in separation processes of gases which operate at pressures greater than 30 bar, with selectivity for carbon dioxide (CO.sub.2).

Disclosed is a thin film composite hollow fiber that includes an outer support layer having a thickness of 10 to 1000 μm and a polyamide thin film layer having a thickness of 1 to 10000 nm; and has a transmembrane pressure resistance rate of higher than 15 bar and a pure water permeability rate of higher than 0.8 Lm.sup.−2h.sup.−1bar.sup.−1. Also disclosed are methods of preparing the above-described support and composite hollow fiber.

The invention proceeds from a filter device which is provided for stabilising a liquid, having at least one filter unit, a membrane filter unit, which has at least one filter element and at least one integrated stabiliser. It is proposed that the filter unit has at least one further integrated stabiliser. It is proposed in a further aspect of the invention that the filter device comprises at least one first precursor which is provided for forming the filter element at least partially, and the same first precursor is provided for forming the stabiliser at least partially.

A carbon membrane for fluid separation, i.e., a fiber-form carbon membrane for fluid separation, has protrusions having a height difference of at least 1 μm formed on the fiber surface. In the carbon membrane for fluid separation, adhesion between membranes is inhibited and clogging tends not to occur when a gas mixture containing water vapor is separated. A carbon membrane module for fluid separation that includes the fibrous carbon membrane for fluid separation is also disclosed.

The present invention provides a hollow fiber membrane including a cellulose acetate-based polymer, in which when an inner surface of the hollow fiber membrane is observed under an atomic force microscope, a plurality of groove-like recesses oriented in a lengthwise direction of the hollow fiber membrane are observed, an average length of the recesses is greater than or equal to 200 nm and less than or equal to 500 nm, an average width of the recesses is greater than or equal to 15 nm and less than or equal to 50 nm, and an aspect ratio defined as a ratio of the average length to the average width of each of the recesses is greater than or equal to 6 and less than or equal to 22.

There is provided a hollow fiber membrane for vacuum membrane distillation having a maximum tensile strength of a ≥3.5 MPa and a liquid entry pressure (LEP) of ≥3.0 bar, wherein the hollow fiber membrane is a single layer hollow fiber membrane comprising a wall with a thickness of ≤150 μm and a cross-section comprising two open cell layers with an array of interconnected pores and a macrovoid layer between the two open cell layers. The hollow fiber has improved mechanical strength and vacuum membrane distillation flux.

Providing new distilling and/or de-scaling methods and systems herein is a matter of allowing for thermal balance without the need to fill a hot wet emulsion separation system with more steam and heat rejection devices to waste steam. A solutions set begins with efficiently utilizing three types of waste: (1) de-oiled and/or cooled down produced water; (2) blowdown steam from drum-type boilers (DBs); and (3) return condensate of dry steam from the DBs. It ends with: (1) removing calcium hardness, magnesium hardness and silica, thereby recovering them as useful minerals; and (2) producing distillate for viscous oil recovery by steam injection and de-scaled hot brine for improved oil recovery by hot water flooding and/or other related methods. The vehicle to attain this solutions' set is a multi-effect distillation train comprises a backward feed section along with two flashing stages.