Filter media comprising non-woven fiber webs and having one or more advantageous structural properties are generally described. In some embodiments, a filter media and/or non-woven fiber web described herein has one or more properties that are both beneficial and easily obtainable by undulating the non-woven fiber web, such as by performing a creping procedure. This property may be characteristic of the procedure employed to form the undulations (e.g., creping and/or microcreping), or may be attainable via one or more methods of undulation.

A filter media for implementation in a sugar purification process that allows for a significant increase in sorbent material while maintaining, and enhancing the decolorization and. hydraulic properties. The filter media incorporates sorbent material, fiber having specific properties that allows for small particle sorbent material without jeopardizing the hydraulic properties of the media, and an electrolyte. The sorbent material is an inorganic, an adsorption, or ion exchange media, or a metal-organic framework. The implementation of this filter media in a sugar purification process eliminates the need for a clarification step during refining while providing for enhanced decolorization and hydraulic properties for fluid flow.

Disclosed is a filter medium useful for flue gas filtering that comprises a non-woven fibrous web having at least 80 weight percent of meta-aramid fibers and from 0.1 to 20 weight percent of meta-aramid fibrids, based on weight of fibers and fibrids. The non-woven fibrous web can have average pore size of 20 to 80 micrometers, maximum pore size of 100 micrometers, dry Mullen burst strength of at least 7 kg/cm.sup.2, retention of 80% of the dry Mullen burst strength after acid cycling, a filtration efficiency of at least 95% for 2.5 micron particle, and/or a shrinkage of less than 2% after being heated in a dry oven at 205 ° C. for 2 hours. A method of making the filter medium comprises wet-laying a furnish of the meta-aramid fibers and the meta-aramid fibrids; drying to form the non-woven fibrous web; preferably, calendering; and optionally saturating with binder resin and curing.

Filter material, mainly in form of industrial remnants from the production of the filter fillings, is processed without the intake of the heat in such a way that it is cut in the disintegrator (4) at the presence of the air, where the material is during retention time repeatedly led to the contact with the rotating blades and bunches emerge in the disintegrator (4) through aeration. The flat carrier (3) is thus at least partially disintegrated to the original fibers (1); the released fibers (1) intertwine into bunches and the active carbon (2) is released from the original bond with the flat carrier (3). The swirl (vortex) created inside the disintegrator (4) carries the dust particles of the active carbon (2) and they adhere to the surface of the fibers (1). Part of the released active carbon (2) is—after the separation—carried away from the emergin bunches, which in the lower part of the disintegrator (4) run through the sieve out of the disintegrator (4). The resulting product is advantageously applicable as heat and noise isolation in all fields of technology, for example construction. The separated active carbon (2) in form of granules is also a resulting product of processing.

Filter media and filters comprising a fibrous material, a bonding material, and a flame-resistant treatment composition are disclosed herein. Methods of making and using the same are also disclosed herein.

Filter media comprising water-repellent additives having minimal or no fluorine atoms are generally provided. In some embodiments, the water-repellent additives comprise one or more water-repellent functional groups. The water-repellent functional groups may comprise a carbon chain including three or more carbon atoms. In some embodiments, some or all of the water-repellent functional group(s) are bonded to a silicon atom and/or a metal atom. It is also possible for some or all of the water-repellent functional group(s) to form side chain(s) attached to a polymer backbone.

Filter media including a filtration layer comprising fibers (e.g., synthetic fibers) comprising a flame retardant and related components, systems, and methods associated herewith are provided. In some embodiments, a filtration layer may include a nonwoven web (e.g., wet-laid nonwoven web) comprising fibers including a certain flame retardant that has a relatively low concentration of or is substantially free of certain undesirable and/or toxic components (e.g., halogens). In certain embodiments, the nonwoven web may also comprise a blend of fibers. For instance, in some embodiments, the nonwoven web may also comprise a blend of coarse and fine diameter synthetic fibers that impart beneficial performance properties to the filtration layer. In some embodiments, the filtration layer may be designed to have a desirable flame retardancy (e.g., F1 rating, K1 rating) and performance properties without compromising certain mechanical properties (e.g., pleatability of the media) and/or environmental attributes (e.g., relatively low toxicity). Filter media described herein may be particularly well-suited for applications that involve filtering air, though the media may also be used in other applications.

The present invention relates to a filter medium, a filter arrangement for the filtration of gas-particle systems comprising such a filter medium, a method for depleting pathogens and/or allergens from the air and other gases by means of such a filter medium, and the use of the filter medium for depleting pathogens and/or allergens from the air and other gases. The filter medium includes at least one acid-functionalized layer comprising at least one carrier material and at least one fruit acid having a pks1 value of 0 to 7. The at least one acid-functionalized layer is free of added C.sub.8 to C.sub.18 fatty acids and their esters and amides thereof. The at least one acid-functionalized layer contains the at least one fruit acid in an amount of 2 wt. % to 30 wt. %, based on the total weight of the at least one acid-functionalized layer.

The present invention provides compositions comprising cellulose fibers and cellulose ester fibers and wet laid articles made from the compositions, as well as wet laid processes to produce these compositions. More specifically, the present invention provided compositions comprising cellulose fibers and cellulose acetate fibers and wet laid articles made from these compositions as well as wet laid processes to produce these compositions. The present invention also relates to developing a composition, process, wet laid product, or articles exhibiting any one of many desired benefits. The present invention relates a filtration article comprising a wet-laid composition comprising cellulose fibers and staple fibers.

Filter media comprising polyethersulfone, related components, and related methods are generally described.