High-Efficiency NO_XAbsorption in Water Using Equipment Packed with a Glass Fiber Filter

Abstract

NO(X) absorption in water is quite difficult by comparison with other exhausted gas, such as SO(2), CO(2), and NH(3) because of low solubility of NO(X) in water. We have been developed a NO(X) absorption equipment with a glass fiber filter having high porosity and surface area. When feed NO(X) gas concentration was high, high NO(X) removal efficiency was obtained. This was because the surface area per glass fiber filter volume was about 40 to 600 times higher than for common packing materials. For verification test and industrial application, a high concentration of NO(X) gas (206,000 ppm) produced by a metal dissolution process was treated with a series of two absorption experiments. We can attain 97.6% of NO(X) removal efficiency, and HNO(3) concentration in water was concentrated up to 56.3 wt %. Furthermore, ozone addition to gas and usage of ozone saturated water as an absorbent resulted in complete removal of NO(X) in the gas (up to 120 ppm). This result indicated the importance of aqueous phase oxidation of HNO(2), which produces NO in the gas phase.

NO Removal with Efficient Recovery of N2O by Using Recyclable Fe3O4@EDTA@Fe(II) Complex: A Novel Approach toward Resource Recovery from Flue Gas

“…Coal combustion is a major source of flue gas emissions, which contain nitrogen oxides (NO x ) and sulfur dioxide (SO 2 ). These pollutants have numerous negative impacts on aquatic life, human health, environmental balance, and ozone depletion. − Compared to SO 2 , NO x is a relatively challenging to handle, as NO, which accounts for 90–95% of the NO x , has poor water solubility and cannot be removed through a simple alkali absorption process in the same way as SO 2 . , To facilitate the absorption of NO, metal complexes such as EDTA–Fe­(II) that can rapidly react with NO and form dissolved metal-nitrosyl complexes (e.g., EDTA–Fe­(II)–NO) have been employed. , This process is widely known as the wet scrubbing method for NO removal. Since the regeneration of metal complexes can be achieved by directly using SO 2 from the flue gas as the reductant source (i.e., via formation of SO 3 2– after absorption by the scrubber), the wet scrubbing method is of particular interest for the simultaneous removal of NO and SO 2 without additional chemical consumption. , …”

“…1−3 Compared to SO 2 , NO x is a relatively challenging to handle, as NO, which accounts for 90−95% of the NO x , has poor water solubility and cannot be removed through a simple alkali absorption process in the same way as SO 2 . 4,5 To facilitate the absorption of NO, metal complexes such as EDTA−Fe(II) that can rapidly react with NO and form dissolved metal-nitrosyl complexes (e.g., EDTA−Fe(II)−NO) have been employed. 6,7 This process is widely known as the wet scrubbing method for NO removal.…”

Catalytic NO Oxidation in the Presence of Moisture Using Porous Polymers and Activated Carbon

“…Similarly, absorption may provide an alternative control option for NO x . While this idea was recognized >40 yr ago, , NO x absorption has gained research traction over the past 5 yr due to continued need for improved stationary source NO x control. − NO, which comprises >90% of NO x in combustion flue gas, has low solubility in water (<1 mg/L) . NO 2 , however, is up to 254 times more soluble (based on Henry’s Law constants at 25 °C) and reacts with water to produce HNO 3 , , improving absorption efficiency.…”

A portable microcolumn based on silver nanoparticle functionalized glass fibers and its SERS application

“…It is also a typical material for extraction and absorption as glass fiber affords a much higher surface area than common packing materials for the same filter volume. 15 Specially, a fine capillary structure could be constructed by numerous extremely fine fibers and the glass based material is intrinsically tolerant to biochemical or chemical circumstances, 16 serving as a suitable support material for surface compounds over porous glass and silica gel. 17 And the traditional glass fiber has been extended to wider usage for analytical matrices by chemically modified active coatings.…”