아민 흡수 공정에서 아민은 O2 및 고온에 의해 비가역반응을 일으키며, 이러한 현상을 열화반응이라 한다. 열화반응은 아민의 가치를 떨어뜨릴 뿐만 아니라 부식, fouling과 같은 문제를 일으킨다. 따라서, 본 연구에서는 여러가지 화학흡수제(MEA; monoethanolamine, AMP; 2-amino-2-methyl-propanol, DAM; 1,8-diamino-p-menthane)를 이용하여 i) 50, 120 ℃에서의 흡수평형, ii) CO2 및 CO2/O2 계에서 흡수제의 열화에 따른 농도변화 및 초기열화속도상수, iii) 산소(O2)에 의한 열화 영향을 살펴보았다. DAM은 흡수영역에서 MEA와 AMP에 비해 400~270% 높은 흡수평형부하를 보이며, MEA나 AMP에 비해 흡수/재생영역에서 흡수평형부하가 커 흡수능이 우수하였다. CO2계에서 DAM의 초기열화속도상수는 2.254×10^(-4) cycle^(-1)로 MEA와 AMP의 2.761×10^(-4) cycle^(-1), 2.416×10^(-4) cycle^(-1)에 비해 작아 열화가 늦게 진행되며, O2 주입시 초기열화속도상수는 1.3배 증가하여 2배 증가한 MEA보다 열화 영향이 적었다. 이러한, 일련의 열화반응은 GC chromatogram에서 새로운 peak의 생성과 FT-IR spectrum 분석을 통하여 확인할 수 있었다.

Amine can undergo irreversible reactions by O2 and high temperature in amine scrubbing process and these phenomena are called “degradation”. Degradation causes not only a loss of valuable amine, but also operational problems such as foaming, corrosion and fouling. In this study, using various chemical absorbents(MEA; monoethanolamine, AMP; 2-amino-2-methyl-1-propanol, DAM; 1,8-diamino-p-menthane), we examined the following variable. i) loading ratio of CO2 at 50 ℃ and 120 ℃, ii) concentration variation and initial degradation rate constant of absorbent in CO2 and CO2/O2 system, and iii) effect of degradation by O2. The CO2 loading of 20 wt% DAM was 400% and 270% higher than that of 20 wt% MEA and AMP at 50, respectively and was the largest the difference of CO2 loading between absorption (50 ℃) and regeneration (120℃) condition. The initial degradation rate constant of 20 wt% DAM was 2.254×10^(-4) cycle^(-1) which was slower than that of MEA (2.761×10^(-4) cycle^(-1) and AMP (2.416×10^(-4) cycle^(-1) in CO2 system. Also, it was increased 30% by O2 that effects on the degradation by O2 was less than 100% increased. these degradation reactions was able to identify by formation of new peak in GC and FT-IR spectrum analysis.

CO2 O2 Absorption Degradation Alkanolamine

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