A filtering device is for obtaining a chemical liquid by purifying a liquid to be purified, and has an inlet portion, an outlet portion, a filter A, at least one filter B different from the filter A, and a flow path which includes the filter A and the filter B arranged in series between the inlet portion and the outlet portion and extends from the inlet portion to the outlet portion, in which the filter A includes at least one kind of porous membrane selected from the group consisting of a first porous membrane having a porous base material made of polytetrafluoroethylene and a non-crosslinked coating which is formed to cover the porous base material and contains a perfluorosulfonic acid polymer and a second porous membrane containing polytetrafluoroethylene blended with a perfluorosulfonic acid polymer.

A filtering device is for obtaining a chemical liquid by purifying a liquid to be purified, and has an inlet portion, an outlet portion, a filter A, at least one filter B different from the filter A, and a flow path which includes the filter A and the filter B arranged in series between the inlet portion and the outlet portion and extends from the inlet portion to the outlet portion, in which the filter A includes at least one kind of porous membrane selected from the group consisting of a first porous membrane having a porous base material made of polytetrafluoroethylene and a non-crosslinked coating which is formed to cover the porous base material and contains a perfluorosulfonic acid polymer and a second porous membrane containing polytetrafluoroethylene blended with a perfluorosulfonic acid polymer.

A method of removing carbon dioxide from a carbonate-containing diaminoalkane solution, the method including passing the carbonate-containing diaminoalkane solution through a membrane module, and a method of preparing diaminoalkane including the same.

The apparatus for filtering and dispensing drinking water is disclosed which includes a container having an interior space with a dividing wall defining a first chamber for receiving unfiltered water and a second chamber for storing filtered drinking water, wherein a passage is formed through the interior wall adjacent a bottom surface of the container to provide fluid communication between the first and second chambers, and wherein at least one multi-layered filter pack is disposed across the passage to filter water flowing from the first chamber to the second chamber under force of gravity.

The apparatus for filtering and dispensing drinking water is disclosed which includes a container having an interior space with a dividing wall defining a first chamber for receiving unfiltered water and a second chamber for storing filtered drinking water, wherein a passage is formed through the interior wall adjacent a bottom surface of the container to provide fluid communication between the first and second chambers, and wherein at least one multi-layered filter pack is disposed across the passage to filter water flowing from the first chamber to the second chamber under force of gravity.

Disclosed herein are ceramic selective membranes and methods of forming the ceramic selective membranes by forming a selective silica ceramic on a porous membrane substrate.

Disclosed herein are ceramic selective membranes and methods of forming the ceramic selective membranes by forming a selective silica ceramic on a porous membrane substrate.

There is provided a pleated cartridge filter for high-purity chemicals that minimizes elution of metal from polyethylene into high-purity chemicals and is suitable mainly for a resist manufacturing process. A cylindrical pleated cartridge filter including a cylindrical core, a pleated filter material wound on the core, and caps sealing both ends of the core, wherein the pleated filter material is composed of a filtration membrane and a spacer laminated together, and the spacer is a nonwoven fabric made of polyethylene fibers having a metal element content of less than 40 ppm.

There is provided a pleated cartridge filter for high-purity chemicals that minimizes elution of metal from polyethylene into high-purity chemicals and is suitable mainly for a resist manufacturing process. A cylindrical pleated cartridge filter including a cylindrical core, a pleated filter material wound on the core, and caps sealing both ends of the core, wherein the pleated filter material is composed of a filtration membrane and a spacer laminated together, and the spacer is a nonwoven fabric made of polyethylene fibers having a metal element content of less than 40 ppm.

A polyolefin multilayer microporous membrane includes at least first microporous layers which form both surface layers of the membrane and at least a second microporous layer disposed between the both surface layers, wherein static friction coefficient of one of the surface layers of the polyolefin multilayer microporous membrane against another surface layer in a longitudinal direction (MD) is 1.1 or less, and wherein pore density calculated from an average pore radius measured by mercury porosimetry method and porosity, according to Formula (1) is 4 or more:
Pore density=(P/A.sup.3)×10.sup.4  (1)
wherein A represents the average pore radius (nm) measured by mercury porosimetry method and P represents the porosity (%).