The invention relates to a fibrous nonwoven, in particular for a filter medium, having a first layer, wherein at least one single-piece fiber strand of said first layer has a first fiber portion and a second fiber portion in the longitudinal direction, and wherein the fiber strand has a thickening substantially in said second fiber portion.

A bacterial cellulose-based air filter mesh and use thereof are disclosed. The bacterial cellulose-based air filter mesh comprises a three-layer structure, in which a layer of a bacterial cellulose-based filter mesh is sandwiched by two layers of polymer fiber filter meshes; wherein the polymer fiber filter mesh is a mesh having a uniform grid size formed from polymer fibers by blended-yarn weaving; and the bacterial cellulose-based filter mesh is formed by in-situ synthesis of bacterial cellulose on a non-woven fabric through fermentation by bacteria. The bacterial cellulose-based air filter mesh has better particle filtering effect, better formaldehyde adsorption capacity, better antibacterial performance and good electrostatic capacity; and it can be used for producing gauze windows, air conditioning filters, air purification filters and the like, and has a wide range of applications.

A filter may remove PM.sub.2.5 and/or other airborne pollutants, which filter has fibers of an average diameter of no more than 500 nm, the fibers of at least 90 wt. % polyacrylonitrile, relative to all fibers in the filter; and a catalyst of at least 90 wt. % TiO.sub.2, relative to all catalytic metals in the filter, dispersed onto the fibers. The fibers need not be charged. The TiO.sub.2 may be condensed or precipitated onto the fibers out of a liquid containing the TiO.sub.2 and the fibers by simple methods. The catalyst may be activated by UV irradiation to decompose particulate matter having an average particle size of 2.5 μm or less, i.e., PM.sub.2.5, and/or other airborne pollutants from air. Such filters may be implemented around areas of vehicle traffic, e.g., as elements of traffic lights, and may be used to controllably purify polluted air.

A filter material for use in fuel-water separation has a particle filtration layer and a coalescing layer downstream of, and coupled to, the particle filtration layer. The particle filtration layer is substantially constructed of binder fibers and media fibers. The coalescing layer has at least 70% glass fibers by weight. As another example, a filter material for liquid fuels has a particle filtration layer and a coalescing layer downstream of the particle filtration layer. The particle filtration layer has binder fibers and media fibers and is substantially free of meltblown materials. The ratio of air permeability of the particle filtration layer to air permeability of the coalescing layer ranges from about 3:1 to about 15:1.

The present disclosure relates to an anti-droplet mask filter and an anti-droplet mask comprising the same, and more particularly, to a hydrophobic filter having ridges and an anti-droplet mask comprising the same. The present disclosure is directed to providing a mask filter with improved water repellency performance for effectively preventing the spread of acute respiratory syndrome virus infections.

The super water-repellent anti-droplet nonwoven filter of the present disclosure shows superhydrophobicity with the surface contact angle of 160° or more due to the ridges that form a nanopatterned structure on the surface of hydrophobic fibers and the surface of bonding portions, thereby preventing the adsorption of droplets onto the surface of the filter. Additionally, the super water-repellent anti-droplet nonwoven filter of the present disclosure can capture ultrafine particles such as aerosols due to the nanopatterned structure on the surface of the super water-repellent anti-droplet nonwoven filter.

A process for predicting and adjusting particle removal efficiency of fiber-based filter media based on quantification of disorder. An order parameter may be extracted through Raman spectroscopy or scanning electron microscopy. Production processes may be adjusted to change (e.g., increase) the particle removal efficiency of fiber-based filter media utilizing a predefined correlation between order parameter and particle removal efficiency. The filter media may be utilized in masks, filters, and other applications.

A method of removing carbon dioxide from a gas can include providing a gaseous feed stream including a carbon dioxide gas and adsorbing the carbon dioxide gas with a porous carbon sorbent. The method can further include de-adsorbing the carbon dioxide and combining the carbon dioxide with a substantially pure hydrogen gas to produce at least one of methane and methanol. The adsorbing and de-adsorbing of the carbon dioxide gas can be conducted by an electric swing adsorption.

A mask with at least one filtering layer that includes a fabric made of non-conductive polymer fibers embedded with nanoparticles of two different metals is provided. The population density of the nanoparticles of the two metals on the surface of non-conductive polymer fibers is configured such that the adjacent nanoparticles of the two metals have an average distance of two micrometers or less. The two different metals are selected such that the electric field intensity generated between the nanoparticles of the two different metal through the aerosol particle inactivates the microorganisms that may be inside the aerosol particle. When an aerosol particle comes into contact with the nanoparticles of the two metals, the aerosol acts as an electrolyte between the two metal types and a potential difference and an electric field is generated, through the aerosol particle, between the nanoparticles of the two metals.

Metal nanoparticle agglomerates may convey biocidal activity to surfaces upon which they are deposited and become adhered, such as various air filtration media. Air filtration media may comprise a plurality of fibers having a plurality of metal nanoparticle agglomerates adhered thereto. The metal nanoparticle agglomerates may comprise a plurality of fused, partially fused, or unfused metal nanoparticles that are associated with one another upon a surface of the plurality of the fibers. Suitable metal nanoparticles for promoting biocidal activity against various pathogens, such as viruses and bacteria, may include copper nanoparticles and/or silver nanoparticles. Masks, inline filters, and air filtration systems may incorporate the air filtration media.

The present disclosure provides a filter for removing contaminants from a liquid or gaseous medium including a woven or nonwoven sheet of entangled carbon nanotubes. The present disclosure also provides a method for reducing the concentration of contaminants in a liquid or gaseous medium by contacting the liquid or gaseous medium with the filter.