Electrochemical Reduction System and Methods of Operation Thereof

Abstract

This disclosure provides systems, methods, and apparatus related to electrochemical reduction of gasses. In one aspect, a method includes flowing a gas through a reduction device. The gas is carbon dioxide (CO 2 ) or nitrogen (N 2 ). The reduction device reduces the gas and generates a product stream including the gas, hydrogen (H 2 ), and a chemical. The product stream is flowed through a hydrogen removal device. The hydrogen removal device removes hydrogen from the product stream. The product stream with the hydrogen removed is flowed through the gas reduction device.

What is claimed is: 
     
         1 . A method comprising:
 flowing a gas through a reduction device, the gas being carbon dioxide (CO 2 ) or nitrogen (N 2 ), the reduction device reducing the gas and generating a product stream including the gas, hydrogen (H 2 ), and a chemical;   flowing the product stream through a hydrogen removal device, the hydrogen removal device removes hydrogen from the product stream; and   flowing the product stream with the hydrogen removed through the gas reduction device.   
     
     
         2 . The method of  claim 1 , further comprising:
 prior to flowing the product stream with the hydrogen removed through the gas reduction device, flowing the product stream with the hydrogen removed through an accumulation chamber to remove the chemical from the product stream.   
     
     
         3 . The method of  claim 2 , wherein the accumulation chamber comprises a substantially gas tight chamber. 
     
     
         4 . The method of  claim 1 , further comprising:
 prior to flowing the product stream with the hydrogen removed through the carbon dioxide reduction device, adding additional gas to the product stream with the hydrogen removed.   
     
     
         5 . The method of  claim 4 , wherein a first pressure of gas is flowed through the gas reduction device, and wherein an amount of additional gas is added to the product stream with the hydrogen removed so that the product stream with the hydrogen removed is at the first pressure. 
     
     
         6 . The method of  claim 1 , wherein the gas is carbon dioxide, and wherein the chemical is a chemical from a group ethylene, ethane, carbon monoxide, methane, propylene. 
     
     
         7 . The method of  claim 1 , wherein the gas is nitrogen, and wherein the chemical is a chemical from a group ammonia, urea, and hydrazine. 
     
     
         8 . The method of  claim 1 , wherein the hydrogen removal device is a device from a group an electrochemical hydrogen pump, a palladium membrane, and a thermal metal hydride adsorption device. 
     
     
         9 . The method of  claim 1 , wherein the hydrogen removal device is an electrochemical hydrogen pump, and wherein the electrochemical hydrogen pump is operated at a temperature of about 150° C. to 180° C. 
     
     
         10 . A system comprising:
 a gas reduction device, an inlet of the gas reduction device operable to receive a gas, the gas being nitrogen (N 2 ) or carbon dioxide (CO 2 ), and the gas reduction device operable to generate a product stream including the gas, hydrogen (H 2 ), and a chemical; and   a hydrogen removal device, an inlet of the hydrogen removal device operable to receive the product stream from an outlet of the gas reduction device, the hydrogen removal device operable to remove hydrogen from the product stream, and an outlet of the hydrogen removal device flowing the product stream with the hydrogen removed into the inlet of the gas reduction device.   
     
     
         11 . The system of  claim 1 , wherein the hydrogen removal device is a device from a group an electrochemical hydrogen pump, a palladium membrane, and a thermal metal hydride adsorption device. 
     
     
         12 . The system of  claim 1 , further comprising:
 an accumulation chamber, wherein an inlet of the accumulation chamber is operable to receive the product stream with the hydrogen removed from the hydrogen removal device, wherein the accumulation chamber is operable to remove the product from the product stream, and wherein an outlet of the accumulation chamber is operable to flow the product stream with the hydrogen removed and at least some of the product removed into the inlet of the gas reduction device.   
     
     
         13 . The system of  claim 1 , further comprising:
 a valve, wherein the valve is operable to allow for addition of the gas to the product stream with the hydrogen removed prior to flowing the product stream with the hydrogen removed through the gas reduction device.   
     
     
         14 . The system of  claim 13 , wherein the valve is a 3-way valve or a 4-way valve. 
     
     
         15 . The system of  claim 1 , further comprising:
 at least one pump to pump the gas and the product stream through the system.