Abstract: A packed tower was used to investigate the removal of CO₂ from polluted air using aqueous alkaline solutions. Experiments were conducted with NaOH concentration 0.30—0.97 kmol·m^-3, MEA concentration 0.02—0.50 kmol·m^-3 and DEA concentration 0.10-0.50 kmol·m^-3 at 25 ℃. A mathematical model based on chemical absorption was proposed. The effective gas-liquid interfacial area (a_v) was calculated from the results of CO₂ absorption into aqueous solutions of sodium hydroxide. For the solutions of MEA and DEA, the overall reaction rate constant (k_ov)_expwas obtained from the results of the experiments and a_v calculated from NaOH-CO₂ system. The overall reaction rate of MEA is much higher than that of DEA. The predictions of the theoretical model were compared with the experimental data and results from literature. Both the experimental data and the results from literatures were in good agreement with the model predictions.

Key words:

二氧化碳, 填料塔, 氢氧化钠, 一乙醇胺, 二乙醇胺, 有效相界面积

摘要： 在填料吸收塔中研究了NaOH水溶液(0.30～0.97 kmol·m^-3)以及有机胺水溶液(MEA：0.10～0.50 kmol·m^-3；DEA：0.10～0.50 kmol·m^-3)吸收空气中微量CO₂的过程，并建立了该过程的数学模型，用NaOH水溶液吸收空气中微量CO₂的实验结果估算了填料的有效相界面积a_v，并根据有效相界面积以及有机胺水溶液吸收CO₂的实验结果预测了MEA、DEA水溶液吸收空气中微量CO₂的总反应速率常数(k_ov)_exp.由实验结果计算得到的总反应速率常数与数学模型能很好地吻合.

关键词:

二氧化碳, 填料塔, 氢氧化钠, 一乙醇胺, 二乙醇胺, 有效相界面积