Perovskite catalysts and uses thereof

Abstract

The present disclosure provides perovskite catalytic materials and catalysts comprising platinum-group metals and perovskites. These catalysts may be used as oxygen storage materials with automotive applications, such as three-way catalysts. They are also useful for water or CO 2 reduction, or thermochemical energy storage.

What is claimed is: 
     
         1 . A method of producing hydrogen by thermo-chemical water splitting, the method comprising:
 (a) heating a perovskite catalyst having the formula CaCo 1-x Zr x O 3-δ  wherein x is a number defined by 0.02≤x≤0.98; and δ is a number defined by 0.0≤δ≤1.0 to release oxygen and generate an oxygen-depleted perovskite catalyst; and   (b) contacting the oxygen-depleted particles with water to release hydrogen and regenerate the perovskite catalyst.   
     
     
         2 . The method of  claim 1 , wherein the hydrogen is produced in a fluidized bed reactor. 
     
     
         3 . The method of  claim 2 , wherein the fluidized bed reactor is a circulating fluidized bed reactor, a bubbling fluidized bed reactor, a transport reactor or a chemical looping reactor. 
     
     
         4 . The method of  claim 1 , wherein the hydrogen is produced in a fixed bed reactor. 
     
     
         5 . The method of  claim 1 , wherein the perovskite catalyst is heated to a temperature of about 400° C. to about 1000° C. 
     
     
         6 . The method of  claim 1 , further comprising using the hydrogen produced in a subsequent reactor to reduce CO 2  to CO and H 2 O. 
     
     
         7 . The method of  claim 1 , further comprising using the hydrogen produced in a subsequent reactor to reduce CO 2  or CO to hydrocarbons and H 2 O. 
     
     
         8 . The method of  claim 1 , further comprising using the hydrogen produced in a subsequent reactor to reduce CO 2  or CO to alkanes or alkenes and H 2 O. 
     
     
         9 . The method of  claim 1 , further comprising using the hydrogen produced in a subsequent reactor to produce aldehydes from mixtures of CO and alkenes. 
     
     
         10 . The method of  claim 1 , further comprising using the hydrogen produced in a subsequent reactor for hydrotreating or hydroprocessing to upgrade crude or heavy petroleum or biomass oil feedstocks. 
     
     
         11 . The method of  claim 6 , wherein the CO 2  is produced in a chemical looping combustion fuel reactor. 
     
     
         12 . A method of reducing CO 2  to CO, the method comprising:
 (a) heating a perovskite catalyst having the formula CaCo 1-x Zr x O 3-δ  wherein x is a number defined by 0.02≤x≤0.98; and δ is a number defined by 0.0≤δ≤1.0 to release oxygen and generate an oxygen-depleted perovskite catalyst; and   (b) contacting the oxygen-depleted perovskite catalyst with CO 2  to remove oxygen, release CO and regenerate the perovskite catalyst.   
     
     
         13 . A system for the thermo-catalytic splitting of water to produce hydrogen, the system comprising:
 (a) an oxygen evolution reactor to heat a perovskite catalyst having the formula CaCo 1-x Zr x O 3-δ  wherein x is a number defined by 0.02≤x≤0.98; and δ is a number defined by 0.0≤δ≤1.0 to generate an oxygen-depleted perovskite catalyst and release oxygen;   (b) a hydrogen evolution reactor to react the oxygen-depleted perovskite catalyst with water vapor and to regenerate the perovskite catalyst and produce hydrogen; and   (c) a device configured to return the regenerated perovskite catalyst to the oxygen evolution reactor.   
     
     
         14 . The system of  claim 13 , wherein the oxygen evolution reactor is a fluidized bed reactor. 
     
     
         15 . The system of  claim 13 , wherein the hydrogen evolution reactor is a fluidized bed reactor. 
     
     
         16 . The system of  claim 13 , wherein the hydrogen evolution reaction fluidized bed is a riser reactor. 
     
     
         17 . The method of  claim 13 , wherein either the oxygen evolution reactor or the hydrogen evolution reactor is a fixed bed reactor. 
     
     
         18 . The system of any of  claim 13 , wherein the hydrogen is used to reduce CO 2  in an exhaust gas from a combustion process. 
     
     
         19 . The system of any of  claim 13 , wherein the hydrogen is used for thermal energy storage. 
     
     
         20 . The system of any of  claim 13 , wherein the system is integrated into a chemical manufacturing system and facility that provides energy for water splitting reactions while minimizing the energy losses.