Organic Amine Modification And CO₂ Capture Performance

As human society continues to progress,the increased use of fossil fuels has led to a rapid rise in atmospheric CO₂concentration,which has led to an increasing greenhouse effect.Therefore,improving the technology of capturing CO₂is an effective measure to achieve carbon reduction.The organic amine CO₂capture technology is a mature CO₂capture technology,which has the characteristics of large absorption capacity,good absorption effect and easy recycling of absorbent.However,this capture technology still has certain disadvantages,therefore more efficient organic amine absorbers need to be developed.In thispaper,neworganicamine structures,2-（（3-aminopropyl）（ethyl）amino）ethanol（HEEPDA）and4-amino-1-hydroxypropyl piperidine（4-A1HDPPD）,were designed and synthesized,and the CO₂capabilities of the two new organic amines were comprehensively evaluated and compared with those of MEA（ethanolamine）and others.The main works are as follows.（1）Design routes for the preparation of HEEPDA and 4-A1HDPPD,and optimize their process routes separately,including the effects of process conditions such as feed mode,material ratio,reaction temperature and reaction time on the reaction yields.（2）HEEPDA offers improved CO₂capture capability:The absorption capacity of HEEPDA was 34.7%,139.8%and 126.4%higher than that of 3-diethylaminopropylamine（DEAPA）,ethanolamine（MEA）and N-methyldiethanolamine（MDEA）under the same absorption conditions,respectively;the initial absorption rates of HEEPDA was faster,about 2.05×10^-2mol/（L·min）,compared to 1.8×10^-2mol/（L·min）for MEA and DEAPA;the equilibrium solubility of HEEPDA was 15-25%higher than that of DEAPA under different conditions;the initial desorption rate of HEEPDA was 3.96×10^-2mol/（L·min）,faster than that of MEA and DEAPA,and HEEPDA has a 90%higher circulation capacity;the lower viscosity of HEEPDA facilitates the CO₂absorption and mass transfer process,HEEPDA has a better CO₂capture capability;（3）4-A1HDPPD has relatively excellent CO₂capture performance:The CO₂uptake of 4-A1HDPPD was 18%and 12.5%higher than that of4-Aminopropylpiperidine（4-A1PPD）and MEA at the same moment,respectively;the CO₂uptake rate of 4-A1HDPPD was relatively fast at1.65×10^-2mol/（L·min）;the equilibrium solubility of 4-A1HDPPD was13%-21%higher than that of 4-A1PPD under different conditions,and4-A1HDPPD had a larger cycling capacity;the desorption rate of4-A1HDPPD was relatively fast,larger than that of 4-A1PPD and MEA,and the desorption rate reached 55.6%within 60 min,compared to 49.2%for 4-A1PPD and MEA was 29.7%,which means that 4-A1HDPPD has relatively excellent CO₂capture performance.