SCI和EI收录∣中国化工学会会刊

›› 2017, Vol. 25 ›› Issue (5): 572-580.DOI: 10.1016/j.cjche.2016.10.015

• Separation Science and Engineering • 上一篇    下一篇

Modification of CaO-based sorbents prepared from calcium acetate for CO2 capture at high temperature

Xiaotong Liu1,2,3, Junfei Shi1,2,3, Liu He1,2,3, Xiaoxun Ma1,2,3, Shisen Xu4   

  1. 1 School of Chemical Engineering, Northwest University, Xi'an 710069, China;
    2 Chemical Engineering Research Center of the Ministry of Education for Advanced Use Technology of Shanbei Energy, Xi'an 710069, China;
    3 Shaanxi Research Center of Engineering Technology for Clean Coal Conversion, Xi'an 710069, China;
    4 China Huaneng Group Clean Energy Technology Research Institute, Beijing 100098, China
  • 收稿日期:2016-09-19 修回日期:2016-10-30 出版日期:2017-05-28 发布日期:2017-07-06
  • 通讯作者: Xiaoxun Ma,E-mail address:maxym@nwu.edu.cn
  • 基金资助:
    Supported by Capture CO2 and Storage Technology Jointly Studied by USA and China (2013DFB60140-04),and Northwest University Graduate Innovative Talent Training Project (YZZ12036).

Modification of CaO-based sorbents prepared from calcium acetate for CO2 capture at high temperature

Xiaotong Liu1,2,3, Junfei Shi1,2,3, Liu He1,2,3, Xiaoxun Ma1,2,3, Shisen Xu4   

  1. 1 School of Chemical Engineering, Northwest University, Xi'an 710069, China;
    2 Chemical Engineering Research Center of the Ministry of Education for Advanced Use Technology of Shanbei Energy, Xi'an 710069, China;
    3 Shaanxi Research Center of Engineering Technology for Clean Coal Conversion, Xi'an 710069, China;
    4 China Huaneng Group Clean Energy Technology Research Institute, Beijing 100098, China
  • Received:2016-09-19 Revised:2016-10-30 Online:2017-05-28 Published:2017-07-06
  • Supported by:
    Supported by Capture CO2 and Storage Technology Jointly Studied by USA and China (2013DFB60140-04),and Northwest University Graduate Innovative Talent Training Project (YZZ12036).

摘要: CaO-based sorbent is considered to be a promising candidate for capturing CO2 at high temperature. However, the adsorption capacity of CaO decreases sharply with the increase of the carbonation/calcination cycles. In this study, CaO was derived from calcium acetate (CaAc2), which was doped with different elements (Mg, Al, Ce, Zr and La) to improve the cyclic stability. The carbonation conversion and cyclic stability of sorbents were tested by thermogravimetric analyzer (TGA). The sorbents were characterized by N2 isothermal adsorption measurements, scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results showed that the cyclic stabilities of all modified sorbents were improved by doping elements, while the carbonation conversions of sorbents in the 1st cycle were not increased by doping different elements. After 22 cycles, the cyclic stabilities of CaO-Al, CaO-Ce and CaO-La were above 96.2%. After 110 cycles, the cyclic stability of CaO-Al was still as high as 87.1%. Furthermore, the carbonation conversion was closely related to the critical time and specific surface area.

关键词: CO2 capture, CaO-based sorbent, Carbonation conversion, Cyclic stability, Critical time, Mesoporous structure

Abstract: CaO-based sorbent is considered to be a promising candidate for capturing CO2 at high temperature. However, the adsorption capacity of CaO decreases sharply with the increase of the carbonation/calcination cycles. In this study, CaO was derived from calcium acetate (CaAc2), which was doped with different elements (Mg, Al, Ce, Zr and La) to improve the cyclic stability. The carbonation conversion and cyclic stability of sorbents were tested by thermogravimetric analyzer (TGA). The sorbents were characterized by N2 isothermal adsorption measurements, scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results showed that the cyclic stabilities of all modified sorbents were improved by doping elements, while the carbonation conversions of sorbents in the 1st cycle were not increased by doping different elements. After 22 cycles, the cyclic stabilities of CaO-Al, CaO-Ce and CaO-La were above 96.2%. After 110 cycles, the cyclic stability of CaO-Al was still as high as 87.1%. Furthermore, the carbonation conversion was closely related to the critical time and specific surface area.

Key words: CO2 capture, CaO-based sorbent, Carbonation conversion, Cyclic stability, Critical time, Mesoporous structure