Carbon Dioxide Captured from Flue Gas by Modified Ca-based Sorbents in Fixed-bed Reactor at High Temperature

作     者：YANG Lei YU Hongbing WANG Shengqiang WANG Haowen ZHOU Qibin 

作者机构：College of Environmental Science and Engineering Nankai University Tianjin 300071 China 

出 版 物：《Chinese Journal of Chemical Engineering》 (中国化学工程学报（英文版）)

年 卷 期：2013年第21卷第2期

页      面：199-204页

核心收录：

学科分类：080706[工学-化工过程机械] 081702[工学-化学工艺] 08[工学] 0817[工学-化学工程与技术] 0807[工学-动力工程及工程热物理] 

基　　金：Supported by the National Natural Science Foundation of China (21006053)  the Fundamental Research Funds for the Central Universities (65010551) and Special Projects of Environmental Protection (2009ZX07208) 

主　　题：CO2 capture carbonation reaction fixed-bed reactor multicycle reaction 

摘      要：Four kinds of Ca-based sorbents were prepared by calcination and hydration reactions using different precursors： calcium hydroxide, calcium carbonate, calcium acetate monohydrate and calcium oxide. The CO2 absorption capacity of those sorbents was investigated in a fixed-bed reactor in the temperature range of 350-650 ℃. It was found that all of those sorbents showed higher capacity for CO2 absorption when the operating temperature higher than 450 ℃. The CaAc2-CaO sorbent showed the highest CO2 absorption capacity of 299 mg.g-1. The mor- phology of those sorbents was examined by scanning electron microscope （SEM）, and the changes of composition before and after carbonation were also determined by X-ray diffraction （XRD）. Results indicated that those sorbents have the similar chemical compositions and crystalline phases before carbonation reaction [mainly Ca（OH）2], and CaCO3 is the main component after carbonation reaction. The SEM morphology shows clearly that the sorbent pores were filled with reaction products after carbonation reaction, and became much denser than before. The N2 adsorption-desorption isotherms indicated that the CaAc2-CaO and CaCO3-CaO sorbents have higher specific surface area. lar2er oore volume and anoropriate pore size distribution than that of CaO-CaO and Ca（OH）2-CaO.