Regulation of Oxygen Activity by Lattice Confinement over NixMg1−xO Catalysts for Renewable Hydrogen Production
Hao Tian,
Chunlei Pei,
Sai Chen,
Yang Wu,
Zhijian Zhao,
Jinlong Gong
Affiliations
Hao Tian
Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China
Chunlei Pei
Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China
Sai Chen
Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China
Yang Wu
Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China
Zhijian Zhao
Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China
Jinlong Gong
Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China; Joint School of National University of Singapore and Tianjin University, International Campus of Tianjin University, Binhai New City, Fuzhou 350207, China; Corresponding author.
The chemical looping steam reforming (CLSR) of bioethanol is an energy-efficient and carbon-neutral approach of hydrogen production. This paper describes the use of a NixMg1−xO solid solution as the oxygen carrier (OC) in the CLSR of bioethanol. Due to the regulation effect of Mg2+ in NixMg1−xO, a three-stage reaction mechanism of the CLSR process is proposed. The surface oxygen of NixMg1−xO initially causes complete oxidation of the ethanol. Subsequently, H2O and bulk oxygen confined by Mg2+ react with ethanol to form CH3COO* followed by H2 over partially reduced NixMg1−xO. Once the bulk oxygen is consumed, the ethanol steam reforming process is promoted by the metallic nickel in the stage III. As a result, Ni0.4Mg0.6O exhibits a high H2 selectivity (4.72 mol H2 per mole ethanol) with a low steam-to-carbon molar ratio of 1, and remains stable over 30 CLSR cycles. The design of this solid-solution OC provides a versatile strategy for manipulating the chemical looping process.
