Experimental Study On The Single And Blended Solvents Regeneration Of A CO₂-Loaded Solution Using Different Solid Acid Catalysts

The increasing emissions of carbon dioxide?CO₂?,the most abundant greenhouse gas?GHG?produced through human activities,is blamed for the increasing global warming and climate change issues.CO₂ is produced mainl y due to the intensive use of fossil fuels for power generation and other industrial activities.[1]CO₂ capture and storage?CCS?is considered to be one of the most efficient ways as well as a major option to control CO₂ emissions,and as such,global warming and climate change.Various single and blended amines?namely,MEA,MEA-DEEA,MEA-MDEA,MEA-1DMA2P?with three types of catalysts(H-ZSM-5,MCM-41 and SO₄^2-/ZrO₂)were studied to determine the respective roles of catalyst and solvent in heat duty for solvent regeneration and rate of CO₂ desorption during the desorption of CO₂ from the solvents having an initial CO₂ loading of 0.5 mol CO₂/mol amine at 371 K.The results show that performance of the three catalysts in all the four investigated aqueous solution systems followed the trend:H-ZSM-5>MCM-41>SO₄^2-/ZrO₂.These results highlight the fact that even though HZSM-5 has moderate acidic sites?MAS?as compared to MCM-41 and SO₄^2-/ZrO₂,its large Br?nsted/Lewis?B/L?acid sites ratio coupled with mesopore surface area?MSA?had the greatest effect on heat duty for CO₂ desorption as well as rate of CO₂ desorption.Furthermore,based on this study,the blended system of aqueous 5M MEA+1M MDEA with H-ZSM-5 provided the best approach for solution regeneration because the strong electron withdrawing chemical structure of MDEA made the solution most prone to CO₂ desorption as compared with 1DMA2P and DEEA.