CO2 Capture Performance of CaO-Based Sorbents Prepared by a Sol鈥揋el Method

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• 作者：Pan Xu ; Miaomiao Xie ; Zhenmin Cheng ; Zhiming Zhou
• 刊名：Industrial & Engineering Chemistry Research
• 出版年：2013
• 出版时间：August 28, 2013
• 年：2013
• 卷：52
• 期：34
• 页码：12161-12169
• 全文大小：527K
• 年卷期：v.52,no.34(August 28, 2013)
• ISSN：1520-5045

文摘

The CaO-based sorbents are considered to be promising candidates for capturing CO₂ from postcombustion of fossil fuels, and how to improve the sintering-resistant performance of the sorbents at high temperature is a challenge for researchers. In this paper, a series of CaO-based sorbents, which consisted of active CaO and inert Ca₉Al₆O₁₈ acting as the support matrix, was synthesized by a sol鈥揼el method with various calcium precursors. The structural properties of the resulting sorbents were characterized by N₂ physisorption, X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), and energy dispersive spectrometry (EDS) techniques, showing that the sorbents prepared by the sol鈥揼el method possessed small grains, interconnected pore network as well as uniform distribution of CaO and Ca₉Al₆O₁₈. These features gave rise to enhanced CO₂ capture performance of the synthetic sorbents compared to pure CaO. In particular, the sorbent with a CaO content of 90 wt % (weight fraction) derived from calcium lactate displayed the best performance for CO₂ capture during a long-term cyclic operation, whose CO₂ capture capacity remained as high as 0.59 g_CO2/g_sorbent at the 35th carbonation-calcination cycle. Finally, this sorbent was applied to the sorption-enhanced steam methane reforming process for hydrogen production, and all the conversion or concentration profiles obtained in 10 consecutive reforming-regeneration cycles almost overlapped, further demonstrating the excellent performance of the sol鈥揼el-derived CaO-based sorbent.