Ca_(2)Fe_(2)O_(5)催化剂对半焦基DC-SOFC性能的影响  

Effect of Ca_(2)Fe_(2)O_(5) catalyst on the performance of DC-SOFC with semi-coke fuel

作　　者：刘国阳[1] 周安宁[1] 刘倩 王俊哲 LIU Guoyang;ZHOU Anning;LIU Qian;WANG Junzhe(School of Chemistry and Chemical Engineering,Xi’an University of Science and Technology,Xi’an 710054,Shaanxi,China;Shaanxi Coal Industry New Energy Technology Co.,Ltd.,Xi’an 710199,Shaanxi,China)

机构地区：[1]西安科技大学化学与化工学院,陕西西安710054 [2]陕西煤业新型能源科技股份有限公司,陕西西安710199

出　　处：《煤炭学报》2024年第3期1647-1656,共10页Journal of China Coal Society

基　　金：陕西煤业新型能源科技股份有限公司研究资助项目;榆林市科技计划资助项目(CXY-2022-148);陕西省创新能力支撑资助计划(2019TD-021)。

摘　　要：半焦与CO_(2)的气化反应速率是影响半焦燃料基DC-SOFC电池性能的关键。为提高半焦的CO_(2)气化反应性,采用柠檬酸溶胶-凝胶法制备了具有钙钛矿结构的Ca_(2)Fe_(2)O_(5)催化剂,用SEM、XRD、XPS、低温氮气吸脱附等分析手段研究了Ca_(2)Fe_(2)O_(5)催化剂的形貌和结构,采用热重分析实验研究Ca_(2)Fe_(2)O_(5)催化剂对半焦燃料的CO_(2)气化反应催化活性;在Ag-GDC|YSZ|GDC-Ag电解质支撑电池系统上,研究了添加Ca_(2)Fe_(2)O_(5)催化剂对半焦燃料基DC-SOFC输出性能的影响。结果表明,随着催化剂焙烧温度的提高,Ca_(2)Fe_(2)O_(5)催化剂晶粒尺寸逐渐增大、比表面积降低,750℃焙烧的催化剂具有良好的分散性、颗粒尺寸约为0.1μm,在半焦的CO_(2)气化反应中催化作用最好;相较于CaO和Fe2O3,Ca_(2)Fe_(2)O_(5)催化剂结构中吸附氧浓度更高,在半焦的CO_(2)气化反应中表现出更为优异的催化活性;Ca_(2)Fe_(2)O_(5)催化剂的循环稳定性取决于催化剂结构的热稳定性,其循环使用时活性降低主要归因于半焦燃料中无机灰分的包裹。催化剂对DC-SOFC输出性能影响表明,当半焦中添加10%的Ca_(2)Fe_(2)O_(5)催化剂时,电池的峰值功率密度从15.3 mW/cm^(2)增大到23.7 mW/cm^(2);EIS分析表明阳极传质阻力是影响DC-SOFC输出性能和燃料利用率的主要因素,降低灰分、催化剂累积带来的传质阻力可有效提高电池寿命和燃料利用率。Semi-coke is an excellent candidate fuel for direct carbon-solid oxide fuel cell(DC-SOFC),and its gasification reaction rate with CO_(2) is the key factor that effects the performance of DC-SOFC fueled semi-coke.In order to improve the gasification reactivity of semi-coke with CO_(2),the Ca_(2)Fe_(2)O_(5) catalyst with perovskite structure has been prepared using citric acid sol-gel method.The morphology and structure of the Ca_(2)Fe_(2)O_(5) catalyst has been investigated using SEM,XRD,XPS,low-temperature nitrogen adsorption-desorption methods.The catalytic activity of Ca_(2)Fe_(2)O_(5) catalyst in the gasification reaction of semi-coke with CO_(2) has been studied by thermogravimetric measurements.The effect mechanism of the semi-coke fuel added Ca_(2)Fe_(2)O_(5) catalyst on the output performance of DC-SOFC has been investigated using Ag-GDC|YSZ|GDC-Ag electrolyte supported DC-SOFC.The results indicate that as the calcination temperature of the catalyst increases,the grain size of Ca_(2)Fe_(2)O_(5) catalyst gradually increases and the specific surface area decreases.The catalyst calcined at 750℃has good dispersibility and a particle size of approximately 0.1μm exhibits the best catalytic activity in the gasification reaction of semi-coke and CO_(2).Compared to the CaO and Fe2O3,the Ca_(2)Fe_(2)O_(5) catalyst structure has a higher concentration of adsorbed oxygen,which is more conducive to its catalytic effect.In the gasification reaction of semi-coke and CO_(2),the cyclic stability of Ca_(2)Fe_(2)O_(5) catalyst depends on the thermal stability of the catalyst structure.During the cyclic use of the catalyst,the decrease in catalytic activity is mainly attributed to the encapsulation of inorganic ash in the semi-coke fuel.Research on the performance of DC-SOFC shows that when 10%Ca_(2)Fe_(2)O_(5) catalyst has been added to the semi-coke,the peak power density of the cell increases from 15.3 mW/cm2 to 23.7 mW/cm2.The EIS analysis shows that the anode mass transfer resistance is the main factor affecting the o

关 键 词：直接碳固体氧化物燃料电池 钙钛矿 催化剂 C-CO_(2)气化反应 

分 类 号：TM911.4[电气工程—电力电子与电力传动]