Air Purification Apparatuses, Systems, and Methods for Removing Particulates, Volatile Organic Compounds, and Nitrous Oxide-Containing Compounds

A method for filtering air in an enclosed environment, the method comprising:

• monitoring carbon dioxide concentration in an enclosed environment;
• initiating an air purification cycle;
• directing an airflow to an air inlet of an air filtration unit, said air filtration unit comprising:
• an air duct having a longitudinal axis, said air duct comprising an air inlet at a first end and an air outlet at a second end;
• a high efficiency particulate air filter unit oriented proximate to the air inlet;
• an airflow controller in communication with the air inlet;
• a carbon dioxide sensor in communication with the airflow controller;
• a pressure sensor in communication with the airflow controller;
• an ultraviolet light reactor, said ultraviolet light reactor comprising;
• a plurality of baffles, each of the plurality of baffles having a plurality of airflow spaces allowing airflow therethrough, said plurality of baffles disposed at spaced locations within the air duct between the air inlet and air outlet, said plurality of baffles each being generally transverse to the longitudinal axis;
• a plurality of ultraviolet light emitting diodes mounted on each baffle;
• a porous and permeable photocatalytic oxidation filter module disposed between each pair of baffles, generally transverse to the longitudinal axis, such that air flows through the porous and permeable photocatalytic oxidation filter module;
• a porous and permeable nitrous oxide-adsorbing filter disposed downstream of the ultraviolet light reactor;
• removing an amount of particulate from the airflow upstream from the porous and permeable photocatalytic oxidation filter module;
• illuminating the porous and permeable photocatalytic oxidation filter module with ultraviolet light from ultraviolet light emitting diodes mounted on each baffle;
• chemically reducing volatile organic compounds in the airflow to non-volatile organic compounds;
• removing an amount of nitrous oxide-containing compounds from the airflow downstream from the porous and permeable photocatalytic oxidation filter module;
• and
• wherein said porous and permeable photocatalytic oxidation filter module contains one or more catalyst, said one or more catalyst comprising at least one of pure titanium dioxide (TiO2), TiO2 doped with iron (Fe—TiO2), TiO2 doped with carbon (C—TiO2), or combinations thereof which, when illuminated by ultraviolet light, are operative to chemically reduce volatile organic compounds to non-volatile organic compounds.