Method and apparatus for decomposing nitrogen oxide

Abstract

A method for decomposing nitrogen oxide includes: contacting a gas stream comprising nitrogen oxide with a device, the device comprising: a first electrode, an opposite second electrode, an electrolyte between the first and the second electrodes, and a power supply; and applying in a pulse mode an electrical current from the power supply to the first and the second electrodes to decompose nitrogen oxide. An associated apparatus is also described.

What is claimed is: 
     
         1 . A method for decomposing nitrogen oxide, comprising:
 contacting a gas stream comprising nitrogen oxide with a device, the device comprising: a first electrode, an opposite second electrode, an electrolyte between the first and the second electrodes, and a power supply; and   applying in a pulse mode an electrical current from the power supply to the first and the second electrodes to decompose nitrogen oxide.   
     
     
         2 . The method of  claim 1 , wherein the step of applying the electrical current is at a temperature in a range of from 300° C. to 1000° C. 
     
     
         3 . The method of  claim 1 , wherein in the pulse mode the electrical current is applied for a time period different from a time period when the electrical current is stopped. 
     
     
         4 . The method of  claim 1 , wherein in the pulse mode the electrical current is applied for a time period the same as a time period when the electrical current is stopped. 
     
     
         5 . The method of  claim 1 , wherein the electrical current is direct current. 
     
     
         6 . The method of  claim 1 , wherein the first electrode is an anode. 
     
     
         7 . The method of  claim 1 , wherein the first electrode comprises a material for oxidizing oxygen ions to oxygen. 
     
     
         8 . The method of  claim 1 , wherein the second electrode is a cathode. 
     
     
         9 . The method of  claim 1 , wherein the second electrode comprises a material for decomposing nitrogen oxide. 
     
     
         10 . The method of  claim 1 , wherein the device comprises an adsorption layer disposed over the second electrode. 
     
     
         11 . The method of  claim 1 , wherein the second electrode comprises an adsorption material for adsorbing nitrogen oxide. 
     
     
         12 . The method of  claim 1 , wherein the apparatus is of a tubular configuration or a planar configuration. 
     
     
         13 . The method of  claim 1 , wherein the device comprises a current collector. 
     
     
         14 . An apparatus for decomposing nitrogen oxide, comprising:
 a gas source for providing a gas stream comprising nitrogen oxide; and   a device in fluid communication with the gas source and comprising: a first electrode, an opposite second electrode, an electrolyte between the first and the second electrodes, and a power supply comprising a controller for applying in a pulse mode an electrical current from the power supply to the first and the second electrodes to decompose nitrogen oxide.   
     
     
         15 . The apparatus of  claim 14 , wherein the first electrode is an anode. 
     
     
         16 . The apparatus of  claim 14 , wherein the second electrode is a cathode. 
     
     
         17 . The apparatus of  claim 14 , wherein the second electrode comprises an adsorption material for adsorbing nitrogen oxide. 
     
     
         18 . The apparatus of  claim 14 , wherein the device comprises an adsorption layer disposed over the second electrode. 
     
     
         19 . The apparatus of  claim 14 , wherein the device comprises a current collector. 
     
     
         20 . The apparatus of  claim 14 , wherein the gas source is an exhaust gas source.