Theoretical and experimental investigations have been performed to obtain carbonic anhydrase (CA) mimic catalysts that are effective for CO₂ absorbents containing highly concentrated amines. One of the most serious problems associated with such absorbents is the inhibition of catalysts due to strong binding of the reaction products—bicarbonates and alkylcarbonates—as well as amine compounds at the active site of the catalysts. The active form of the CA mimic catalyst, M–OH, must be formed prior to the binding of such inhibitors. Taking into account the fact that OH^– is a Lewis base that is harder than the inhibitors, we focus on hard Lewis acids, in particular, boron compounds, on the basis of the Hard and Soft Acids and Bases principle. With the aid of density functional theory (DFT) calculations, we experimentally confirm that triphenylborane and boric acid derivatives are efficient catalysts for CO₂ absorption in an aqueous solution of 30 wt % 2-(isopropylamino)ethanol. The DFT calculations predict that the intrinsic reactivity toward CO₂ is improved, while the resistance to inhibitions is reduced, as the hardness of the boron center is decreased.

中文翻译：

---

硼化合物催化烷醇胺水溶液中CO ₂吸收的计算与实验研究

已经进行了理论和实验研究以获得对含有高浓度胺的CO ₂吸收剂有效的碳酸酐酶（CA）模拟催化剂。与这种吸收剂有关的最严重的问题之一是由于反应产物碳酸氢盐和烷基碳酸盐以及胺化合物在催化剂活性位点的牢固结合而抑制了催化剂。CA模拟催化剂的活性形式M-OH必须在与这类抑制剂结合之前形成。考虑到一个事实，即OH ^-是一种比抑制剂硬的路易斯碱，基于硬酸和软酸和碱原理，我们主要研究硬路易斯酸，特别是硼化合物。借助密度泛函理论（DFT）计算，我们实验确定三苯硼烷和硼酸衍生物是在30 wt％2-（异丙基氨基）乙醇水溶液中吸收CO _2的有效催化剂。DFT计算预测，随着硼中心硬度的降低，对CO ₂的固有反应性得到改善，而对抑制的抵抗力降低。