摘要
碱金属基吸收剂干法脱除燃煤烟气CO_2技术日益受到学术界的关注,其中钠基吸收剂廉价易得、经济性好,但碳酸化反应活性低。本文将Na_2CO_3负载于活性氧化铝并掺杂TiO_2改性,利用CO_2吸收/解吸流化床试验装置、XRD、SEM和氮吸附仪研究钠基二氧化碳吸收剂的流化床反应特性。结果表明:TiO_2对Na_2CZO_3/Al_O_3在流化床中的碳酸化反应特性提升明显,反应时间缩短、反应速度提高、CO_2吸收量增加;碳酸化反应产物为NaHCO_3和Na_5H_3(CO_3)_4;TiO_2对再生反应影响甚微;且TiO_2在反应前后性状稳定,无副产物生成。尽管如此,TiO_2的掺杂量应控制在一定的范围内以避免吸收剂微观结构恶化而阻碍反应。
Development of sodium-based solid sorbents for decreasing CO_2 emission from coal-fired power plants is receiving more and more attention.Its carbonation behaviors have been studied recently,and it is understood that its primary downfall is the slow reaction with CO_2 during adsorption process.TiO_2 is examined as a potential dopant for sodium-based solid sorbent based CO_2capture process in a bubbling fluidized-bed.SEM,XRD and nitrogen adsorption characterizations of Na_2CO_3/Al_2O_3 doped with TiO_2 indicate that TiO_2 is stable within the temperature range necessary for such a process.More importantly,TiO_2 has a positive effect on the carbonation of Na_2CO_3and the reaction rate,as well as the CO_2 uptake,is observed to increase obviously.Carbonate reaction products are NaHCO_3 and Na_5H_3(CO_3)_4.TiO_2 has little effect on the regeneration of sorbent.Despite this,the loading of TiO_2 should be limited,because too much TiO_2 doped may block the microstructure of sorbent which is unfavourable to carbonate reaction.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2015年第1期210-214,共5页
Journal of Engineering Thermophysics
基金
国家自然科学基金(No.51476030)
高等学校博士学科点专项科研基金(No.20130092110006)
