A method for purifying a liquid is described. A liquid feed is fed to a feed chamber. A carrier gas is fed through the liquid feed in the feed chamber to form a humidified carrier gas. A coolant is fed to a coolant chamber. The coolant chamber is separated from the feed chamber by an air gap chamber. The air gap chamber is separated from the feed chamber by a membrane that allows vapor to pass while blocking liquid flow across the membrane. The coolant chamber is separated from the air gap chamber by a thermally conductive plate. At least a portion of the vapor from the feed chamber that transported through the membrane is condensed by the coolant in the coolant chamber and the thermally conductive plate to form a first distillate. At least a portion of the humidified carrier gas is condensed to form a second distillate.

An air dehydration module includes polymeric fibers for separating water vapor from air, and also includes a carbon filter material, positioned at an outlet end of the module, and within the same pressure vessel which houses the fibers. The module may generate its own sweep stream, in which case a portion of its output is directed to flow through an orifice, towards the inlet end of the module. In an alternative embodiment, the sweep gas is produced by a distinct gas-separation module, which receives an input stream from the output of the dehydration module. The dehydration module produces clean and dry air which can be used as is, or as an input stream to an air separation module.

In one embodiment, a separation membrane includes: a porous support structure; and at least one alkali metal hydroxide disposed within pores of the porous support structure. In another embodiment, a method for separating acidic gases from a gas mixture includes exposing the gas mixture to a separation membrane at an elevated temperature, where the separation membrane includes a porous support and at least one molten alkali metal hydroxide disposed within pores of the porous support.

Internally reheated sweep gas-aided membrane gas separation module in which the sweep gas is expanded retentate that is warmed through heat exchange with non-expanded retentate within the module.

A method for removing hydrogen sulfide from a liquid stream is described. The method includes contacting the liquid stream including a first amount of hydrogen sulfide with a first side of a porous gas-liquid separation membrane. The hydrogen sulfide moves through the pores of the membrane from the first side to a second, opposite side of the membrane. The method further includes contacting a receiving fluid with the second, opposite side of the porous membrane to receive the hydrogen sulfide. The liquid stream is thus converted to a reduced-sulfide liquid stream having a second amount of hydrogen sulfide that is less than the first amount of hydrogen sulfide. A method for removing ammonia from a liquid stream is also described.

Equipment, systems, processes and techniques for conducting processing of solutions are described. The techniques can be applied to provide diluted solution (i.e. purified solvent), concentrate solution or each. A variety of specific equipment, example systems and processes are depicted and described.

The present application is directed to systems and methods for on-board fuel separation. The system includes: a source fuel tank for liquid fuel; a pump; and a membrane module. The membrane module includes a hydrophilic membrane, a retentate channel, and a permeate channel. The retentate and permeate channels are on opposing sides of the membrane. The membrane module receives fuel from the source fuel tank and separates the liquid fuel into a high octane fraction that collects in the retentate channel and a low octane fraction that diffuses through the membrane to the permeate channel. The system further includes a low octane fuel tank for receiving at least a portion of the low octane fraction, a high octane fuel tank for receiving at least a portion of the high octane fraction, and an engine configured to selectively receive at least a portion of the low and high octane fractions.

A process for producing nitrogen-rich air by feeding high temperature air at 150 C. or more to an air separation membrane module is described. After being placed at 175 C. for two hours, the air separation module exhibits a shape-retention ratio of 95% or more in one embodiment. The nitrogen-rich air can be fed to a fuel tank for an aircraft, for example.

A process for producing nitrogen-rich air by feeding high temperature air at 150 C. or more to an air separation membrane module is described. After being placed at 175 C. for two hours, the air separation module exhibits a shape-retention ratio of 95% or more in one embodiment. The nitrogen-rich air can be fed to a fuel tank for an aircraft, for example.

Equipment, systems, processes and techniques for conducting processing of solutions are described. The techniques can be applied to provide diluted solution (i.e. purified solvent), concentrate solution or each. A variety of specific equipment, example systems and processes are depicted and described.