Air Purifier for Transportation Vehicles

Abstract

A vehicle air purification system has a photocatalyst activated by photons emitted via an ultraviolet light emitting diode (UV-LED). The photocatalyst on a supporting structure is positioned to contact airflow passing through or over the photocatalyst. Chemical contaminants and microorganisms are eliminated from the airflow that makes contact with the photocatalyst structure.

What is claimed is: 
     
         1 . A transportation vehicle air purification system comprising:
 a housing having inlet and outlet for the air to be purified to enter and leave the housing;   an ultraviolet light emitting diode (UV-LED) that is arranged to emit ultraviolet (UV) radiation; and   a photocatalyst structure disposed in a distance from the UV-LED, wherein:   the photocatalyst structure is placed inside of the housing,   the UV LED is positioned to emit ultraviolet radiation onto the photocatalyst structure, and   the photocatalyst structure is positioned to contact airflow passing through or over the photocatalyst structure.   
     
     
         2 . The air purification system of  claim 1 , wherein the system is an automobile cabin or car cabin air cleaning system. 
     
     
         3 . The air purification system of  claim 1 , wherein the system is an airplane cabin air cleaning system. 
     
     
         4 . The air purification system of  claim 1 , wherein the system is a boat cabin air cleaning system. 
     
     
         5 . The air purification system of  claim 1 , further comprising several ultraviolet light emitting diodes (UV-LEDs). 
     
     
         6 . The air purification system of  claim 5 , wherein the UV-LEDs emit radiant power of different peak wavelengths. 
     
     
         7 . The air purification system of  claim 1 , wherein the ultraviolet radiation is emitted in any range from 250 nm to 385 nm. 
     
     
         8 . The air purification system of  claim 1 , further comprising several photocatalyst structures, wherein the photocatalyst structures are made of similar or different photocatalyst components. 
     
     
         9 . The air purification system of  claim 1 , wherein the photocatalyst structure is a photocatalyst supported on a porous substrate, mesh, screen, metal foam, cloth, paper, or a combination thereof. 
     
     
         10 . The air purification system of  claim 1 , wherein the photocatalyst is titanium dioxide (TiO 2 ) based. 
     
     
         11 . The air purification system of  claim 1 , further comprising an air-moving unit, such as an electrical fan, configured to create airflow in the housing. 
     
     
         12 . The air purification system of  claim 1 , further comprising one or more baffles for enhancing airflow distribution through or over the photocatalyst structure. 
     
     
         13 . The air purification system of  claim 1 , further comprising one or more filters such as carbon filter and high-efficiency particulate air (HEPA) filter. 
     
     
         14 . The air purification system of  claim 1 , further comprising an air quality sensor, wherein the system is turned on and off automatically by a signal from the air quality sensor. 
     
     
         15 . The air purification system of  claim 1 , wherein the system has the shape of a cylinder, prism, frustum, hyperboloid, ellipsoid, paraboloid, sphere, or torus. 
     
     
         16 . The air purification system of  claim 15 , comprising two ends, wherein the airflow flows in and out from a first end and the system is placed inside a vehicle cup holder from a second end. 
     
     
         17 . The air purification system of  claim 1 , wherein the system has the shape of a popular beverage container such as coffee tumbler, cup, mug, or beverage can. 
     
     
         18 . A method of purifying airflow in transportation vehicles, comprising:
 passing the airflow through a reactor including one or more photocatalyst structures;   emitting ultraviolet radiation from one or more ultraviolet light emitting diodes (UV-LEDs) onto the photocatalyst structure; and   eliminating chemical contaminants and microorganisms from the airflow that makes contact with the photocatalyst structure while the photocatalyst is activated by the ultraviolet radiation emitted from the UV-LED.   
     
     
         19 . The method of  claim 18 , wherein the reactor is a mobile stand-alone reactor to be placed inside or be connected into a transportation vehicle passenger cabin. 
     
     
         20 . The method of  claim 18 , wherein the reactor is part of a transportation vehicle air ventilation or air circulation system.