O2鈥揅O2 Mixed Gas Production Using a Zr-Doped Cu-Based Oxygen Carrier
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- 作者：Minjun Wang ; Jing Liu ; Jianbo Hu ; Feng Liu
- 刊名：Industrial & Engineering Chemistry Research
- 出版年：2015
- 出版时间：October 14, 2015
- 年：2015
- 卷：54
- 期：40
- 页码：9805-9812
- 全文大小：644K
- ISSN：1520-5045
文摘
Oxyfuel combustion using O2鈥揅O2 mixed gas as the oxidant is a promising technology for effectively capturing high concentration CO2. Chemical looping air separation (CLAS) is a novel approach with a low energy footprint for O2鈥揅O2 mixed gas production. In this work, a series of Zr-doped Cu-based oxygen carriers were prepared by the sol鈥揼el combustion method and used to produce the O2鈥揅O2 gas mixture. The effects of doping Zr on phase structure, surface topography, O2 absorption/desorption, and cyclic reaction of Cu-based oxygen carriers were studied by experiments. The influencing mechanism of Zr doping on O2 release of Cu-based oxygen carrier was investigated using density functional theory (DFT) calculations. The results indicate that the addition of Zr enlarges the specific surface area and refines the grains. The Zr-doped Cu-based oxygen carriers have high desorption reaction rates. The oxygen release capacity increases with the increasing Zr doping amount. The cyclic operation indicates that the Zr-doped Cu-based oxygen carriers have high cyclic stability. The DFT calculation results show that, compared with the pure CuO, the Zr-doped CuO has lower oxygen vacancy formation energy, lower energy barriers for oxygen desorption and O anion diffusion, and narrower band gap, which indicates that the Zr-doped CuO releases oxygen more easily than the pure CuO and has a lower energy barrier of electron transfer, thus leading to a higher reactivity.