Medium-entropy perovskite oxygen carrier and preparation method and application thereof

Patent metadata

Field	Value
Publication number	US-2024116771-A1
Application number	US-202318202730-A
Country	US
Kind code	A1
Filing date	May 26, 2023
Priority date	Oct 8, 2022
Publication date	Apr 11, 2024
Grant date	—

Abstract

The present disclosure relates to the technical field of oxygen carrier, discloses a medium-entropy perovskite oxygen carrier and its preparation method and application thereof, the synthesis procedure includes preparing an aqueous solution from metallic nitrate serving as a raw material, performing a coprecipitation reaction with at least one of aqueous ammonia solution, a sodium hydroxide aqueous solution or a sodium carbonate aqueous solution as a precipitant at a pH value of 9.5 to 10.5; obtaining the La 3 CoMnAlO 9 powers after stirring, standing, washing, drying and calcining. The preparation method is simple, synthetic conditions are easy to control, and batch production could be achieved.

First claim

1 . A preparation method of a medium-entropy perovskite oxygen carrier, including:
(1) preparing an aqueous solution from metallic nitrate serving as a raw material, and performing a coprecipitation reaction with at least one of aqueous ammonia solution, a sodium hydroxide aqueous solution or a sodium carbonate aqueous solution as a precipitant at a pH value of 9.5 to 10.5, to obtain a hydroxide precursor; and (2) obtaining a La 3 CoMnAlO 9 medium-entropy perovskite oxygen carrier after stirring, standing, washing, drying and calcining.

2 . The preparation method according to claim 1 , wherein the metallic nitrate is La(NO 3 ) 3 ·6H 2 O, Co(NO 3 ) 3 ·6H 2 O, a Mn(NO 3 ) 2 aqueous solution and Al(NO 3 ) 3 ·9H 2 O; an ionic molar ratio of La to Co to Mn to Al is 3:1:1:1.

3 . The preparation method according to claim 1 , wherein, a mixing manner of the precipitant and the metallic nitrate solution is one of forward dropwise adding, cocurrent or reverse dropwise adding.

4 . A medium-entropy perovskite oxygen carrier, wherein the medium-entropy perovskite oxygen carrier is prepared by claim 1 .

5 . Application of the medium-entropy perovskite oxygen carrier according to claim 4 in a reaction of chemical-looping reforming of methane to hydrogen in a fluidized bed, wherein at a reduction stage, the oxygen carrier reacts with the methane under an oxygen-free condition, the methane is partially oxidized by lattice oxygen in the oxygen carrier to generate syngas, and meanwhile the oxygen carrier is reduced; at the re-oxidation stage, the oxygen carrier reacts with steam, to obtain part of the lattice oxygen, and meanwhile hydrogen is generated; at an air combustion stage, the oxygen carrier is further oxidized by air to be cyclically regenerated, so that the oxygen carrier restores to a structure before reacting with the methane.

6 . The application according to claim 5 , wherein reaction temperatures of the reduction stage and the oxidation stage are 700° C. to 1100° C.

7 . The application according to claim 5 , wherein, mixed gas of methane and nitrogen is introduced at the reduction stage, wherein a volume percentage of the methane is 5% to 100%, and with benchmarking against methane, a volume space velocity of the reaction is controlled to be 120 h −1 to 12000 h −1 .

8 . The application according to claim 5 , wherein mixed gas of steam and nitrogen is firstly introduced at the oxidation stage, wherein a volume percentage of the steam is 5% to 100%, and with benchmarking against steam, a volume space velocity of the reaction is controlled to be 120 h −1 to 12000 h −1 .

9 . The medium-entropy perovskite oxygen carrier of claim 4 , wherein the metallic nitrate is La(NO 3 ) 3 ·6H 2 O, Co(NO 3 ) 3 ·6H 2 O, a Mn(NO 3 ) 2 aqueous solution and Al(NO 3 ) 3 ·9H 2 O; an ionic molar ratio of La to Co to Mn to Al is 3:1:1:1.

10 . The medium-entropy perovskite oxygen carrier of claim 4 , wherein, a mixing manner of the precipitant and the metallic nitrate solution is one of forward dropwise adding, cocurrent or reverse dropwise adding.

Assignees

• Univ Tianjin

Inventors

• Gong Jinlong
• Zhang Xianhua
• Pei Chunlei
• Zhao zhi-jian
• Yao Xian
• Liu Yifan

Classifications

• C01F17/34 Primary

  Aluminates, e.g. YAlO3 or Y3-xGdxAl5O12 · CPC title

• C01P2002/34

  perovskite-type (ABO3) · CPC title

• C01G51/70 Primary

  containing rare earths, e.g. LaCoO3  (C01G51/68 takes precedence) · CPC title

• Y02P20/133

  Renewable energy sources, e.g. sunlight · CPC title

• B01J23/002 Primary

  Mixed oxides other than spinels, e.g. perovskite · CPC title