A method of and apparatus for obtaining potable water from the exhaust of an internal combustion engine is disclosed essentially comprising separating a water vapor permeate containing water vapor and noncondensable gases from the exhaust by a nonporous nonionic hydrophilic membrane, then separating the water vapor from noncondensable gases by either condensing the water vapor or compressing the entire water vapor permeate followed by condensation of the water vapor contained in the permeate.

Hybrid membrane-based separation systems are disclosed that are useful in separating solvents and solutes. The hybrid systems combine any of the solvent removal processes reverse osmosis, nanofiltration, membrane distillation and pervaporation with any one of more of the solute removal processes utilizing pervaporation membranes, supported-liquid membranes, coupled transport membranes, and membrane contactors, the solvent and solute removal processes forming part of a recycle stream that utilize...

An improvement to processes for the selective extractation of organic solutes from organic solvents by water-based extractants is disclosed, the improvement comprising coupling various membrane separation processes with the organic extraction process, the membrane separation process being utilized to continuously recycle the water-based extractant and at the same time selectively remove or concentrate organic solute from the water-based extractant.

A gas dehydration method and apparatus are disclosed which utilize lumen-side feed, thin-film which is highly permeable, such composite membranes being used in a module wherein the permeate flows countercurrent to the flow of the feed.

A system for the ultrapurification of organic solvents comprising (1) a membrane-based vapor permeation step for selective removal of water vapor from the solvent, wherein a countercurrent sweep stream is used that has a particular partial pressure of water vapor, (2) a filtration step for selective removal of particulates, and (3) an ion exchange step for selective removal of ionic species.

There is described a process for the removal of at least one component of a liquid mixture, the basic process comprising directing a liquid mixture against the feed side of a membrane, directing a condensable vapor sweep stream past the permeate side of the membrane in a manner such that the flow of the condensable vapor sweep is substantially countercurrent to the flow of the liquid mixture, thereby transporting at least a portion of at least one component of the liquid mixture from the feed si...

The present invention discloses a method for the enzymatic synthesis of a peptide. A protected peptide having a C-terminal carboxylate group or a protected, N-acyl amino acid having an alpha carboxylate group is reacted with a protected peptide having an N-terminal ammonium group or a protected amino acid having an alpha ammonium group in the presence of a condensation enzyme under conditions in which the carboxylate group and the ammonium group condense to form a protected, uncharged, peptide p...

A process for removing and recovering a condensable vapor from a gas stream by a membrane contactor is disclosed wherein a gas stream containing a condensable vapor is circulated on one side of hollow fiber membranes while cool extraction fluid is circulated on the other side under a total pressure differential, thereby condensing the condensable vapor in the gas stream, the condensed vapor permeating the membrane and becoming entrained in the cool extraction fluid.

A gas dehydration method and apparatus are disclosed which utilize lumen-side feed, hydrophilic polymer-inside-coated, thin-film composite hollow fiber membranes, the support fiber of which is highly permeable, such composite membranes being used in a module wherein the permeate flows countercurrent to the flow of the feed, and in which dried raffinate gas is mixed with water-containing permeate at a point opposite the feed end of the module.

A process for the removal of at least one non-water vapor component of a vaporous mixture, the basic process comprising directing a vaporous mixture against the feed side of a membrane, directing a condensable vapor sweep stream past the permeate side of the membrane in a manner such that the flow of the condensable vapor sweep is substantially countercurrent to the flow of the vaporous mixture, thereby transporting at least a portion of at least one non-water vapor component of the vaporous mix...