Department of Physics, Norwegian University of Science and Technology, Hoegskoleringen 5, N-7491 Trondheim, Norway.
Langmuir. 2012 Jan 24;28(3):1678-82. doi: 10.1021/la204164q. Epub 2012 Jan 10.
We show experimentally that gaseous CO(2) intercalates into the interlayer space of the synthetic smectite clay Na-fluorohectorite at conditions not too far from ambient. The mean interlayer repetition distance of the clay when CO(2) is intercalated is found to be 12.5 Å for the conditions -20 °C and 15 bar. The magnitude of the expansion of the interlayer upon intercalation is indistinguishable from that observed in the dehydrated-monohydrated transition for H(2)O, but the possibility of water intercalation is ruled out by a careful analysis of the experimental conditions and repeating the measurements exposing the clay to nitrogen gas. The dynamics of the process is observed to be dependent on the pressure, with a higher intercalation rate at increased pressure. The rate of CO(2) intercalation at the studied conditions is found to be several orders of magnitude slower than the intercalation rate of water or humidity at ambient pressure and temperature.
我们通过实验证明，在环境条件下，气态 CO(2)可以插入合成皂石蒙脱石 Na-fluorohectorite 的层间空间。当 CO(2)插入时，粘土的平均层间重复距离在-20°C 和 15 巴的条件下被发现为 12.5 Å。插入过程中层间的膨胀量与 H(2)O 脱水-一水合转变中观察到的膨胀量难以区分，但通过仔细分析实验条件并重复测量将粘土暴露于氮气中，可以排除水插入的可能性。观察到该过程的动力学取决于压力，在较高压力下插入速度较高。在研究条件下，CO(2)的插入速度比环境压力和温度下水或湿度的插入速度慢几个数量级。
