液压成型法制备钙锰型钙钛矿氧载体及其化学链燃烧性能评价  

Preparation of CaMn_(0.5)Ti_(0.25)Fe_(0.125)Mg_(0.125)O_(3−δ)oxygen carriers via hydroforming method and their performance in chemical looping combustion

作　　者：臧利豪 刘先宇 吴鑫[1] 赵海波[1] ZANG Lihao;LIU Xianyu;WU Xin;ZHAO Haibo(State Key Laboratory of Coal Combustion,Huazhong University of Science and Technology,430074 Wuhan,China)

机构地区：[1]华中科技大学煤燃烧与低碳利用全国重点实验室,武汉430074

出　　处：《煤炭转化》2025年第2期24-34,共11页Coal Conversion

基　　金：国家自然科学基金项目(52025063);湖北省自然科学基金项目(2022CFD035).

摘　　要：氧载体是化学链燃烧技术的灵魂,而以往研究中氧载体通常存在固有缺陷,无法同时满足实际应用中对氧载体的多个性能指标的要求。同时,氧载体的批量制备存在成本较高、效率低下及效果不佳的问题,限制了化学链燃烧技术的进一步发展。基于液压成型法制备了CaMn_(0.5)Ti_(0.25)Fe_(0.125)Mg_(0.125)O_(3−δ)钙钛矿氧载体,并利用球磨法替代普通机械混合来进行前期物料的混合,以期改善物料混合不均的现象,增强氧载体的综合性能。在批次流化床中采用最新提出的甲烷化学链燃烧测试方法探究了球磨时间(1 h,2 h,3 h)、煅烧温度(1050℃,1150℃,1250℃,1350℃)和煅烧时间(4 h,8 h,12 h)这三个核心参数对氧载体性能的影响规律。结果表明:球磨时间影响氧载体的循环稳定性;煅烧温度严重影响氧载体的供氧能力、破碎强度和循环稳定性;煅烧时间影响氧载体的破碎强度和循环稳定性。最佳样品(球磨时间为3 h,煅烧温度为1250℃,煅烧时间为12 h)能实现99%以上的CH_(4)转化率和CO_(2)选择性,反应前后的XRD和SEM-EDS表征表明,氧载体的钙钛矿相形成良好,并具有优异的结构稳定性。The oxygen carrier is the core of chemical looping combustion(CLC)technology.However,in previous studies,oxygen carriers often had inherent limitations and failed to simultaneously meet multiple performance criteria required for practical applications(e.g.,oxygen transport capacity,mechanical durability,and redox stability).Additionally,the large-scale production of oxygen carriers faces challenges such as high costs,low efficiency,and inconsistent performance,limiting the further development of CLC technology.In this study,CaMn_(0.5)Ti_(0.25)Fe_(0.125)Mg_(0.125)O_(3−δ)oxygen carriers were synthesized using the hydroforming method.To improve the mixing uniformity of precursors and enhance the overall performance of the oxygen carriers,ball milling was used to replace conventional mechanical mixing in the initial material preparation stage.Subsequently,the latest methane chemical looping combustion test method was employed in a batch fluidized bed to investigate the effects of three key parameters on the performance of the oxygen carrier:ball milling duration(1 h,2 h,3 h),calcination temperature(1050℃,1150℃,1250℃,1350℃),and calcination time(4 h,8 h,12 h).The results show that the ball milling time affects the cyclic stability of the oxygen carriers,while the calcination temperature significantly influences the oxygen release capacity,crushing strength,and cycling stability.Additionally,the calcination time impacts the crushing strength and cycling stability of the oxygen carriers.The optimal sample,which is ball-milled for 3 h and calcined at 1250℃for 12 h,achieved over 99%CH_(4)conversion and CO_(2)selectivity.XRD and SEM-EDS characterization before and after the reaction indicate that the oxygen carriers exhibit well-formed perovskite phase and excellent structural stability.

关 键 词：化学链燃烧 钙钛矿 氧载体 液压成型法 天然气 

分 类 号：TB34[一般工业技术—材料科学与工程] TQ038[化学工程]