摘要
CaO是一种高效廉价的CO_(2)吸附剂,但其在循环使用过程中易烧结,导致其捕集CO_(2)的能力大幅衰减,无法长周期循环应用。以半惰性Al_(2)O_(3)掺杂CaO制备钙铝复合吸附剂,采用热重吸/脱附的方法研究了复合吸附剂的捕集性能及循环稳定性,并采用室温空气再生方法深入研究了钙铝复合吸附剂的再生性能,建立了再生性能与循环次数的关系。结果表明,因惰性骨架物相Ca3Al2O6的建立与微观纳米结构的形成,Al_(2)O_(3)的掺杂使钙铝复合吸附剂的捕集性能、循环稳定性和再生性能均大大优于纯CaO吸附剂。经100次循环后,钙铝复合吸附剂的CO_(2)吸附容量和碳酸化转化率在n(Ca):n(Al)=10:1时分别可达0.23 g/g和34.0%,在n(Ca):n(Al)=10:2时分别保持在0.19 g/g和32.8%,但n(Ca):n(Al)不宜超过10:2。进一步通过吸附剂的失活数学模型验证发现CaO吸附剂的烧结是不可逆的,Al_(2)O_(3)的掺杂可抑制CaO吸附剂的烧结,同时保持钙铝复合吸附剂的再生活性。经两次空气再生的钙铝复合吸附剂(n(Ca):n(Al)=10:2)的碳酸化转化率基本保持不变,100次循环后仍为32.7%。
CaO is a kind of efficient and cheap CO_(2)capture adsorbents,but it is prone to sintering in the process of recycling,resulting in a significant decrease in capture capacity and making it unsuitable for long-term cyclic applications.Semi-inert Al_(2)O_(3)-doped CaO was used to prepare the calcium-aluminum composite adsorbents.The capture performance and cycle stability of the calcium-aluminum composite adsorbents were studied by thermogravimetric adsorption/desorption method.The regeneration performance of the calciumaluminum composite adsorbents was further studied by air regeneration method at room temperature,and the relationships between regeneration performance and cycle times were established.The results show that the adsorption performance,cycle stability and regeneration performance of calcium-aluminum composite adsorbents are much better than those of pure CaO adsorbents because of the establishment of inert skeleton phase of Ca3Al2O6 and the formation of micro-nano structure.After 100 cycles,the CO_(2)adsorption capacity and carbonation conversion rate of the calcium-aluminum composite adsorbents reach 0.23 g/g and 34.0%respectively when n(Ca):n(Al)=10:1,and remain at 0.19 g/g and 32.8%respectively when n(Ca):n(Al)=10:2,but n(Ca):n(Al)should not exceed 10:2.It is proved by the deactivation mathematical model of the adsorbents that the sintering of CaO adsorbents is irreversible,and the doping of Al_(2)O_(3)can inhibit the sintering of CaO adsorbents and keep the regeneration activity of calcium-aluminum composite adsorbents.The carbonation conversion rate of the calcium-aluminum composite adsorbents(n(Ca):n(Al)=10:2)after regeneration for twice under air remains basically unchanged,which is still 32.7%after 100 cycles.
作者
吴爽
刘瑞
丁巍巍
薛原
王鑫
WU Shuang;LIU Rui;DING Weiwei;XUE Yuan;WANG Xin(Collaborative Innovation Centre of Applicative Technology of Clean Energy Resources in Fujian Province,Quanzhou Vocational and Technical University,Quanzhou 362268,Fujian,China;College of Marine Science and Environment,Dalian Ocean University,Dalian 116023,Liaoning,China;SINOPEC(Dalian)Research Institute of Petroleum and Petrochemicals Co.,Ltd.,Dalian 116045,Liaoning,China)
出处
《低碳化学与化工》
CAS
北大核心
2024年第5期81-87,共7页
Low-Carbon Chemistry and Chemical Engineering
基金
福建省清洁能源应用技术协同创新中心2022年开放课题(QJNY22-05)。