CO2在磷酸三丁酯中溶解度的测定

采用恒定容积压降法测定了温度303.5~363.8 K、压力0.5~4.5 MPa条件下CO2在磷酸三丁酯(TBP)中的溶解度. 结果表明，CO2在TBP中的溶解度随压力升高而增大，但随平衡温度升高而减小；在0~4.5 MPa范围内，该溶解度较在工业常用物理吸收剂中更大，约为在乙醇中的2.4倍，甲醇中的1.4倍，N-甲基吡咯烷酮中的1.2倍及碳酸丙烯酯中的1.1倍. CO2以分子形式溶解于TBP中，TBP吸收CO2以物理吸收为主，TBP中含有的酯键及磷酰基团极大地促进了其对CO2的吸收.

Measurement of CO2 Solubility in Tributyl Phosphate

The solubility of CO2 in tributyl phosphate (TBP) solvent was measured in a temperature range of 303.15～363.15 K and gas pressure of CO2 up to 4.5 MPa by the constant volume method. The results showed that the solubility increased with the augment of CO2 gas pressure and decreased with the rising of equilibrium temperature. GC/MS and FT-IR analysis results indicated that the capture process of CO2 by TBP could be regarded as physical absorption. The Henry’s coefficient which was obtained by fitting of the experimental data was well consistent with the Henry’s law. It confirmed that there was no chemical change during the adsorption process. Comparing the absorption capacity of TBP with other solvents, the CO2 solubility in TBP was 1.4 times higher than that in ethanol and 0.2 times higher than that in N-methyl-2-pyrrolidone under the same conditions.