REMOVING METHOD OF CARBON DIOXIDE IN COMBUSTION EXHAUST GAS

摘要

PURPOSE: To improve absorption capacity synthetically compared with conventional case by using a MEA aq. solution by using a specific pyperazine derivative aq. solution for a combustion exhaust gas under the atmospheric pressure as a liquid absorbent. CONSTITUTION: CO2 in the combustion exhaust gas is removed by bringing the combustion gas under the atmospheric pressure into contact with the pyperazine derivative aq. solution expressed by the formula. Here in the formula, R<1> is a lower alkyl group, R<2> is hydrogen atom or the lower alkyl group. Where, the pyperazine derivative is preferably 2--methyl pyperazine and the concn. of the aq. solution is 15-65wt.%. The 2-methyl pyperazine absorbent has the heat of reaction with CO2 lower than the MEA absorbent in the interval of the large absorbed molar number of CO2 and then is advantageous since the energy necessary for regenerating is smaller than the MEA absorbent.