Process for recovery of hydrogen from coal gasification products

Abstract

A process for recovering hydrogen from coal gasification products is provided. The process comprises contacting the coal gasification products with a metal-based Boudouard catalyst to produce a first product stream comprising hydrogen and carbon dioxide; and contacting the first product stream with a solid phase carbon dioxide adsorbent to separate hydrogen from the first product stream.

1 . A process for recovering hydrogen from coal gasification products, the process comprising: 
 contacting the coal gasification products with a metal-based Boudouard catalyst to produce a first product stream comprising hydrogen and carbon dioxide; and    contacting the first product stream with a solid-phase carbon dioxide adsorbent to separate hydrogen from the first product stream.    
   
   
       2 . The process of  claim 1 , wherein the coal gasification products comprise syngas.  
   
   
       3 . The process of  claim 2 , wherein the coal gasification products comprise nitrogen, methane, carbon dioxide, hydrogen and carbon monoxide.  
   
   
       4 . The process of  claim 3 , wherein the coal gasification products and metal-based Boudouard catalyst are contacted at a temperature of from about 350° to about 900° C.  
   
   
       5 . The process of  claim 3 , wherein the coal gasification products and metal-based Boudouard catalyst are contacted in the presence of steam.  
   
   
       6 . The process of  claim 5 , wherein methane is converted to additional hydrogen and carbon monoxide.  
   
   
       7 . The process of  claim 2 , wherein the coal gasification products comprise carbon monoxide, hydrogen and methane.  
   
   
       8 . The process of  claim 7 , wherein the coal gasification products and metal-based Boudouard catalyst are contacted at a temperature of from about 350° to about 900° C.  
   
   
       9 . The process of  claim 7 , wherein the coal gasification products and metal-based Boudouard catalyst are contacted in the presence of steam.  
   
   
       10 . The process of  claim 9 , wherein methane is converted to additional hydrogen and carbon monoxide.  
   
   
       11 . The process of  claim 1 , wherein the steps of contacting are conducted in a single reactor selected from the group consisting of a fixed bed reactor, a fluidized bed reactor and a packed bed reactor.  
   
   
       12 . The process of  claim 1 , wherein the metal-based Boudouard catalyst comprises metallic iron.  
   
   
       13 . The process of  claim 12 , wherein the process further comprises reducing carbon monoxide in the syngas to form carbon dioxide and hydrogen.  
   
   
       14 . The process of  claim 12 , wherein the process further comprises converting carbon monoxide into carbon dioxide and free carbon.  
   
   
       15 . The process of  claim 1 , wherein the solid phase carbon dioxide adsorbent comprises calcium oxide.  
   
   
       16 . The process of  claim 1 , wherein the reaction is conducted at a pressure of from about 0 to about 250 psi.  
   
   
       17 . The process of  claim 1 , wherein the ratio of metal-based Boudouard catalyst to solid phase carbon dioxide adsorbent is from about 1:3 to about 1:6.  
   
   
       18 . The process of  claim 1 , wherein the process further comprises regenerating the solid phase carbon dioxide adsorbent by contacting the adsorbent with nitrogen; and 
 regenerating the metal-based Boudouard catalyst by contacting the catalyst with oxygen.    
   
   
       19 . A process for recovering hydrogen from coal gasification products, the process comprising: 
 contacting the coal gasification products with a catalyst comprising metallic iron in a reactor at a temperature of from about 350° to about 900° C. to produce a first product stream comprising hydrogen and carbon dioxide;    contacting the first product stream with an adsorbent comprising calcium oxide to separate hydrogen from the product stream;    regenerating the adsorbent by contacting the adsorbent with nitrogen; and    regenerating the catalyst by contacting the catalyst with oxygen.    
   
   
       20 . The process of  claim 19 , wherein the steps of contacting are conducted in a single reactor selected from the group consisting of a fixed bed reactor, a fluidized bed reactor and a packed bed reactor.