One aspect of the invention relates to a method comprising a single-stage conversion of an atmospheric pollutant, such as NO, NO.sub.2 and/or SO.sub.x in a first stream to one or more mineral acids and/or salts thereof by reacting with nonionic gas phase chlorine dioxide (ClO.sub.2.sup.0), wherein the reaction is carried out in the gas phase. Another aspect of the invention relates to a method comprising first adjusting the atmospheric pollutant concentrations in a first stream to a molar ratio of about 1:1, and then reacting with an aqueous metal hydroxide solution (MOH). Another aspect of the invention relates to an apparatus that can be used to carry out the methods disclosed herein. The methods disclosed herein are unexpectedly efficient and cost effective, and can be applied to a stream comprising high concentration and large volume of atmospheric pollutants.

A method of using a burner-based exhaust replication system to generate exhaust that contains nitrogen dioxide (NO.sub.2). An example of such as system is a system used to test automotive exhaust aftertreatment devices. A fluid that decomposes to generate NO.sub.2 as one of its decomposition products is selected. The fluid is heated thereby generating NO.sub.2, with the amount and duration of heating is controlled to result in a desired decomposition extent of NO.sub.2 from the fluid. The fluid is then delivered to an exhaust stream of the system.

Methods for removing reduced sulfur compounds, such as hydrogen sulfide, from fluids employing a ferric iron salt that exhibits unusually high solubility in aqueous, alkaline solutions and has strong affinity for capture and oxidation of reduced sulfur compounds. Alkaline aqueous ferric iron salt and solutions thereof useful for removing reduced sulfur compounds from fluids and various methods of production of such salts and solutions. In addition, methods of regenerating the alkaline aqueous ferric iron salt solutions after capture of hydrogen sulfide or other reduced sulfur compounds, generally by exposure to oxygen in air. The alkali metal carbonate salt preferably comprises potassium carbonate and/or potassium bicarbonate. The alkaline aqueous ferric iron salt solutions generally comprise ferric ions, potassium ions, carbonate ions, and bicarbonate ions, optionally with one or more organic additives. In addition, aqueous-soluble, ferric iron salts and ferric iron containing solids prepared by removal of aqueous medium from solutions herein.

In a method for treating combustible and/or reactive particles (34) which have been separated from a gas stream (32) by means of a separation device (36) an oxidizing agent is supplied to an atmosphere surrounding the particles (34) so as to cause a passivating oxidation of at least a part of the particles (34). A content of the oxidizing agent in the atmosphere surrounding the particles (34) is detected and the supply of the oxidizing agent to the atmosphere surrounding the particles (34) is controlled in dependence on the detected content of the oxidizing agent in the atmosphere surrounding the particles (34).

Methods for removing reduced sulfur compounds, such as hydrogen sulfide, from fluids employing a ferric iron salt that exhibits unusually high solubility in aqueous, alkaline solutions and has strong affinity for capture and oxidation of reduced sulfur compounds. Alkaline aqueous ferric iron salt and solutions thereof useful for removing reduced sulfur compounds from fluids and various methods of production of such salts and solutions. In addition, methods of regenerating the alkaline aqueous ferric iron salt solutions after capture of hydrogen sulfide or other reduced sulfur compounds, generally by exposure to oxygen in air. The alkali metal carbonate salt preferably comprises potassium carbonate and/or potassium bicarbonate. The alkaline aqueous ferric iron salt solutions generally comprise ferric ions, potassium ions, carbonate ions, and bicarbonate ions, optionally with one or more organic additives. In addition, aqueous-soluble, ferric iron salts and ferric iron containing solids prepared by removal of aqueous medium from solutions herein.

Some embodiments of the present disclosure relate to a method of regenerating at least one filter medium comprising: providing at least one filter medium, wherein the at least one filter medium comprises: at least one catalyst material; and ammonium bisulfate (ABS) deposits, ammonium sulfate (AS) deposits, or any combination thereof; flowing a flue gas stream transverse to a cross-section of a filter medium, such that the flue gas stream passes through the cross section of the at least one filter medium, wherein the flue gas stream comprises: NOx compounds comprising: Nitric Oxide (NO), and Nitrogen Dioxide (NO.sub.2); and increasing an NOx removal efficiency of the at least one filter medium after removal of deposits.

A sorbent composition such as for the removal of a contaminant species from a fluid stream, a method for manufacturing a sorbent composition and a method for the treatment of a flue gas stream to remove heavy metals such as mercury (Hg) therefrom. The sorbent composition includes a porous carbonaceous sorbent such as powdered activated carbon (PAC) and a solid particulate additive that functions as a flow-aid to enhance the pneumatic conveyance properties of the sorbent composition. The solid particulate additive may be a flake-like material, for example a phyllosilicate mineral or graphite.

A method for treating sulfur contaminants is provided. The method comprises introducing a methylmorpholine-N-oxide solution to a vessel, wherein the vessel comprises a water layer and a gas layer, wherein the water layer and the gas layer comprise the hydrogen sulfide; introducing methylmorpholine-N-oxide into the water layer; and treating the water layer by allowing the methylmorpholine-N-oxide to react with the hydrogen sulfide.

Some embodiments of the present disclosure relate to a method of regenerating at least one filter medium comprising: providing at least one filter medium, wherein the at least one filter medium comprises: at least one catalyst material; and ammonium bisulfate (ABS) deposits, ammonium sulfate (AS) deposits, or any combination thereof; flowing a flue gas stream transverse to a cross-section of a filter medium, such that the flue gas stream passes through the cross section of the at least one filter medium, wherein the flue gas stream comprises: NO.sub.x compounds comprising: Nitric Oxide (NO), and Nitrogen Dioxide (NO.sub.2); and increasing an NO.sub.x removal efficiency of the at least one filter medium after removal of deposits.

The present invention relates to a vehicle air conditioner, and more particularly, to a vehicle air conditioner having a photocatalyst module, which provides an optimal design location or a mounting structure in which the photocatalyst module is mounted on an upper surface of a duct, the upper surface of the duct has a predetermined inclination with respect to a floor surface, and the photocatalyst module is mounted on a left/right independent air conditioner.