Pentalithium aluminate(β-LiAlO) and the corresponding iron-containing solid solution(Li(AlFe)O)were synthetized by solid-state reaction. All the samples were characterized structural and microstructurally by X-ray ...Pentalithium aluminate(β-LiAlO) and the corresponding iron-containing solid solution(Li(AlFe)O)were synthetized by solid-state reaction. All the samples were characterized structural and microstructurally by X-ray diffraction, solid-state nuclear magnetic resonance, scanning electron microscopy, Nadsorption-desorption and temperature-programmed desorption of CO. Results showed that 30 mol% of iron can be incorporated into the β-LiAlOcrystalline structure at aluminum positions. Moreover, iron addition induced morphological and superficial reactivity variations. Li(AlFe)Osamples chemisorbed CObetween 200 and 700 °C, where the superficial chemisorption presented the highest enhancement,in comparison to β-LiAlO. Additionally, Li(AlFe)Osamples sintered at higher temperatures thanβ-LiAlO. Isothermal COchemisorption experiments of β-LiAlOand Li(AlFe)Owere fitted to a first order reaction model, corroborating that iron enhances the COchemisorption, kinetically. When oxygen was added to the gas flow, COchemisorption process was mainly enhanced between 400 and 600 °C for the Li(AlFe)Osample in comparison to β-LiAlO. Hence, Li(AlFe)Osolid solution presented an enhanced COchemisorption process, in the presence and absence of oxygen, in comparison to β-LiAlO.展开更多
基金financially supported by the Project SENERCONACYT(251801)CONACYT for financial support through the CONACYT-SNI research assistant system and PNPC-CONACYT,respectively
文摘Pentalithium aluminate(β-LiAlO) and the corresponding iron-containing solid solution(Li(AlFe)O)were synthetized by solid-state reaction. All the samples were characterized structural and microstructurally by X-ray diffraction, solid-state nuclear magnetic resonance, scanning electron microscopy, Nadsorption-desorption and temperature-programmed desorption of CO. Results showed that 30 mol% of iron can be incorporated into the β-LiAlOcrystalline structure at aluminum positions. Moreover, iron addition induced morphological and superficial reactivity variations. Li(AlFe)Osamples chemisorbed CObetween 200 and 700 °C, where the superficial chemisorption presented the highest enhancement,in comparison to β-LiAlO. Additionally, Li(AlFe)Osamples sintered at higher temperatures thanβ-LiAlO. Isothermal COchemisorption experiments of β-LiAlOand Li(AlFe)Owere fitted to a first order reaction model, corroborating that iron enhances the COchemisorption, kinetically. When oxygen was added to the gas flow, COchemisorption process was mainly enhanced between 400 and 600 °C for the Li(AlFe)Osample in comparison to β-LiAlO. Hence, Li(AlFe)Osolid solution presented an enhanced COchemisorption process, in the presence and absence of oxygen, in comparison to β-LiAlO.