CO2 gasification of Yangchangwan coal catalyzed by iron-based waste catalyst from indirect coal-liquefaction plant
CO2 gasification of Yangchangwan coal catalyzed by iron-based waste catalyst from indirect coal-liquefaction plant
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DOI：
10.1016/j.fuel.2020.119228
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发表时间：
2021-02
期刊：
影响因子：
7.4
通讯作者：
Xinsha Zhang;Xudong Song;Jiaofei Wang;Weiguang Su;Yonghui Bai;Bing Zhou;G. Yu
中科院分区：
文献类型：
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作者：
Xinsha Zhang;Xudong Song;Jiaofei Wang;Weiguang Su;Yonghui Bai;Bing Zhou;G. Yu
煤焦-CO2气化是一个高能耗的强吸热反应，使用廉价的催化剂是节约工艺成本的关键之一。煤间接液化装置产生的铁基废催化剂中含有活性组分，但其对煤焦气化反应活性的影响尚未见报道。因此，在热重分析仪（TGA）上，以IWC为催化剂，对羊场湾煤（YCW）进行了CO2气化反应。采用傅里叶变换红外光谱（FT-IR）技术研究了煤焦表面官能团的变化。采用聚焦离子束扫描电子显微镜（FIB-SEM）对煤焦的形貌进行了表征。利用X射线衍射（XRD）和X射线光电子能谱（XPS）对铁的物相和价态进行了分析。结果表明，IWC对YCW气化是有效的。在1000-1200 °C范围内，催化气化的最佳温度为1000 °C。YCW气化半焦的FT-IR光谱显示了催化气化过程中-OH、C-O、-CH 2、-CH 3、C=C和Fe-O等小分子活性基团的变化。煤焦表面结构粗糙，存在大量微孔。IWC在0 min时生成的金属Fe最终被气化剂CO2氧化为FeO和Fe 3 O 4。Fe 0、Fe 2+和Fe 3+之间的氧化还原循环是IWC催化YCW-CO2气化反应活性的主要原因。
Coal char-CO2gasification is a strong endothermic reaction with high energy consumption, and a cheap catalyst use is one of the keys to save process costs. The iron-based waste catalyst (IWC) from indirect coal-liquefaction plant contains active component, but its effect on the gasification reactivity of coal char is seldom reported. Thus, CO2gasification of Yangchangwan coal (YCW) was conducted in thermogravimetric analyzer (TGA) with IWC as the catalyst. The change of functional group on coal char surface was measured by a Fourier transform infrared (FT-IR) spectroscopy. The morphology of coal char was characterized by focused ion beam scanning electron microscope (FIB-SEM). X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were employed to analyze phases and valences of iron. The results indicate that IWC was effective for YCW gasification. In the range of 1000–1200 °C, the optimal temperature of catalytic gasification was 1000 °C. The FT-IR spectra of YCW gasified char showed the changes of small molecule active groups, such as –OH, C–O, –CH2, –CH3, C=C and Fe–O in the process of catalytic gasification. The surface structure of coal char was rough and there were lots of tiny pores. The metallic Fe formed by IWC at 0 min was finally oxidized by gasification agent CO2to FeO and Fe3O4. The redox cycle between Fe0, Fe2+and Fe3+is the main reason for the catalytic YCW-CO2gasification reactivity in the presence of IWC.