Abstract: A bi-directional air exchanger for a metal-air battery having a housing. The air exchanger includes an ambient air passageway for a first flow of air in a first direction, a battery exhaust passageway for a second flow of air in a second direction, and one or more membranes. The ambient air passageway and the battery exhaust passageway are separated within the housing by the one or more membranes such that the first and the second flows of air are in fluid communication with one another for the exchange of humidity.

Abstract: Multi-step methods of making a non-skinned isotropic microfiltration membrane, the common steps of which include heating a PVDF-type casting dope above its cloudpoint, forming a film, and immersing the film in a gelation bath.

Abstract: Improved methods of rendering PVDF membranes hydrophilic are disclosed.

Abstract: 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 product. This peptide product is transported across a water-immiscible hydrophobic phase into an aqueous product phase and prevented from back diffusing across the water-immiscible hydrophobic phase. The peptide product can be converted, chemically or enzymatically, to a charged species that cannot back diffuse across the water-immiscible phase into the aqueous reaction phase.

Abstract: There is disclosed a method of separating enantiomers of 4-(3',4'-dichlorophenyl)-3,4-dihydro-1(2H)-naphthalenone comprising contacting the same with a homogeneous or nonhomogeneous liquid mixture of solvent and water, the mixture containing substantially pure and unsupported gamma-cyclodextrin or its derivatives. Also disclosed are methods of further enantiomerically enriching solid mixtures obtained from the enantiomer separation method and further extracting one enantiomer by solvent extraction of the solid mixtures obtained.

Abstract: There are disclosed two types of apparatus using membrane extractions of citrus juice bittering agents, both using extraction fluids. In one type, a membrane contactor facilitates contact between bittering agents present in a citrus juice feed and a hydrophobic bittering agents extraction fluid; a second membrane contactor may be used to extract bittering agents from the hydrophobic extraction fluid by use of a basic stripping fluid on the permeate side. In a second type, an immobilized liquid membrane containing hydrophobic extraction fluid supported within the pores of a microporous hydrophobic polymeric membrane is used to facilitate transport of bittering agents across the membrane.

Abstract: Semipermeable membrane-enclosed solid core adsorbent devices for the selective removal of volatile chemical species from an aqueous environment are disclosed.

Abstract: 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.