Electrocatalytic tube of electrochemical-catalytic converter for exhaust emissions control

Abstract

An electrocatalytic tube for controlling exhaust emissions, which adopts to purify the exhaust, comprises a tube, an anode layer and a cathode layer. The tube is composed of a solid-state electrolyte layer. The solid-state electrolyte layer includes an enclosed chamber, an inner wall formed inside the enclosed chamber, and an outer wall formed outside the enclosed chamber. The enclosed chamber has a sub-atmospheric reducing environment. The anode layer and cathode layer are respectively coated on the inner wall and outer wall of the solid-state electrolyte layer. The reducing environment facilitates an electromotive force to occur between the anode layer and the cathode layer. The electromotive force promotes catalytic decomposition of nitrogen oxides of the exhaust on the cathode layer.

What is claimed is: 
     
         1 . An electrocatalytic tube for controlling exhaust emissions, which adopts to purify the exhaust, comprising:
 a tube, composed of a solid-state electrolyte layer, wherein the solid-state electrolyte layer includes an enclosed chamber, an inner wall formed inside the enclosed chamber, and an outer wall formed outside the enclosed chamber, and wherein the enclosed chamber has a reducing environment; and   an anode layer and a cathode layer respectively coated on the inner wall and the outer wall of the solid-state electrolyte layer, wherein the reducing environment facilitates an electromotive force to occur between the anode layer and the cathode layer, and wherein nitrogen oxides of the exhaust are decomposed into nitrogen and oxygen on the cathode layer, and wherein carbon monoxide, hydrocarbons and particulate matter of the exhaust are oxidized into carbon dioxide and water on the cathode layer.   
     
     
         2 . The electrocatalytic tube for controlling exhaust emissions according to  claim 1 , wherein the reducing environment is sub-atmospheric. 
     
     
         3 . The electrocatalytic tube for controlling exhaust emissions according to  claim 1 , wherein the anode layer is made of a porous material. 
     
     
         4 . The electrocatalytic tube for controlling exhaust emissions according to  claim 1 , wherein the cathode layer is made of a porous material. 
     
     
         5 . The electrocatalytic tube for controlling exhaust emissions according to  claim 1 , wherein the reducing environment includes a gas selected from a group consisting of carbon monoxide and hydrocarbons. 
     
     
         6 . The electrocatalytic tube for controlling exhaust emissions according to  claim 1 , wherein a carbon species adheres to the anode layer. 
     
     
         7 . The electrocatalytic tube for controlling exhaust emissions according to  claim 1 , wherein the electrocatalytic tube has a working temperature ranging from ambient temperature to 600° C. 
     
     
         8 . The electrocatalytic tube for controlling exhaust emissions according to  claim 1 , wherein the anode layer is made of a material selected from a group consisting of cermet of nickel and fluorite metal oxides, perovskite metal oxides, fluorite metal oxides, metal-added perovskite metal oxides, metal-added fluorite metal oxides, and combinations thereof. 
     
     
         9 . The electrocatalytic tube for controlling exhaust emissions according to  claim 1 , wherein the cathode layer is made of a material selected from a group consisting of perovskite metal oxides, fluorite metal oxides, metal-added perovskite metal oxides, metal-added fluorite metal oxides, and combinations thereof. 
     
     
         10 . The electrocatalytic tube for controlling exhaust emissions according to  claim 1 , wherein the solid-state electrolyte layer is made of a material selected from a group consisting of fluorite metal oxides, perovskite metal oxides, and combinations thereof. 
     
     
         11 . The electrocatalytic tube for controlling exhaust emissions according to  claim 1 , wherein a catalytic oxidation layer is adhered to the cathode layer. 
     
     
         12 . The electrocatalytic tube for controlling exhaust emissions according to  claim 11 , wherein the catalytic oxidation layer is made of a material selected from a group consisting of metals, alloys, metal oxides, fluorite metal oxides, perovskite metal oxides, and combinations thereof. 
     
     
         13 . The electrocatalytic tube for controlling exhaust emissions according to  claim 1 , wherein the reducing environment has a pressure of smaller than ½ atm.