引言 当前,以CO2为主的大量温室气体排放,加剧了全球温室效应和气候异常。燃煤电厂是一个重要的、长期的、稳定的CO2固定排放源。因此,捕获和固定电厂烟气中的CO2对减缓当前全球温室效应和气候异常显得尤其重要。
The CaO/FA sorbents were prepared by calcination and hydration reaction using calcium hydroxide and fly ash from Coal-fired power plant waste.The CO2 absorption capacity of CaO/FA sorbents in a fix-bed reactor in temperature range of 350—650℃,and effect of mass ratio of CaO and fly ash on it was investigated.The morphological properties of those sorbents before and after absorbing CO2 were characterized by using XRD,SEM and N2 adsorption-desorption.And a deactivation model was used to fit breakthrough data obtained.The results indicated that,the sorbents have high BET surface area and large pore volume after hydration reaction,CO2 absorption capacity of CaO/FA sorbents increases with rise of reaction temperature,and have the minimum value at 350℃ for all of CaO/FA sorbents.Its increase become not so obvious when the reaction temperature is in the range of 450—650℃.It was also found that CaO/FA sorbents show a maximum CO2 absorption capacity 227.13 mg·g-1 at 650℃ if the mass ratio of CaO and fly ash was 3∶1.After 9 use cycles the CaO/FA sorbents still have high and stable absorption capacity.In addition,CO2 breakthrough curves of CaO/FA sorbents can well be fitted with a deactivation model,and the absorption and deactivation rate constants were obtained.