Research On The Capture Of Carbon Dioxide Using Absorption-Adsorption Coupling Process Of Suspension Slurry Bed

The increasing release of CO₂,mainly derived from the combustion of fossil fuel,has already posed a detrimental effect on the global climate change in terms of exacerbating global warning.It is therefore of great significance to explore strategies that aim to effectively capture CO₂ existing in industrial waste gas,which has caused intensive research attention among the industrial and scientific communities.Solvent absorption is commonly regarded as a relatively mature technology for CO₂ capture,but it still suffers many drawbacks including low absorption capacity,high energy consumption for regeneration,etc.In this context,China University of Petroleum（CUP）proposed a novel strategy for CO₂ capture in which the absorption and adsorption process were elaborately coupled.The as proposed technology made great progress in significantly enhancing the CO₂ capture capacity.Unfortunately,the researches on advancing our understanding to its microscopic mechanism have not been achieved yet,and the basic data of its specific mass transfer process still remain unknown.Raman spectroscopy is commonly regarded as a powerful tool to monitor of structures and compositions of materials especially in the fields of materials science,petroleum,environmental protection and archeology.Benefiting from these,it is anticipated that Raman spectroscopy can brings us hope of uncovering the aforementioned mystery in CO₂ capture.With this in mind,here,Raman spectroscopy is employed to investigate the characteristic of CO₂ dissolution in slurries,and the detailed mass transfer patterns are also analyzed.In addition,the reaction condition for CO₂ capture was optimized,and the regeneration performance was evaluated.This work mainly includes the following two parts:（1）The investigation on the performance of glycol and mixture of glycol and MIM towards CO₂ capture: The dissolution characteristic of CO₂ in glycol and mixed solutions of glycol and MIM was elucidated,thus obtaining the specific relationship among relative solubility of CO₂,height and time.It was found that the introduction of glycol noticeably enhanced the performance of CO₂ capture.Moreover,recovered solutions were inspected by means of Raman spectroscopy,which showed that solutions possess excellent regenerability.（2）The investigation on the effect of the ZIF-8/ glycol slurry upon CO₂ capture: It was demonstrated that only nZIF-8 showed the capacity for CO₂ capture.The detailed mechanism of absorption-adsorption coupling process of ZIF-8/ glycol slurry was further studied by comparing the CO₂ capture performance at different height of the reactor,and the findings indicated that the use of ZIF-8/ glycol slurry did enable the CO₂ capture through absorption-adsorption coupling.Based on the above-mentioned observations,the relationship among relative solubility of CO₂,height and time was thereby established.Meanwhile,the resulting recovered slurry was also monitored,which revealed that the slurry had a good regenerability.In summary,the absorption capacity,stability and regenerability of the slurry were systematically investigated,the results obtained in our experiments showed that the as proposed new technology could integrate the advantages of absorption and adsorption process,thereby exhibiting great potential in the application of CO₂ capture.