Formation of CO2 Hydrates within Single-Walled Carbon Nanotubes at Ambient Pressure: CO2 Capture and Selective Separation of a CO2/H-2 Mixture in Water
Formation of CO2 Hydrates within Single-Walled Carbon Nanotubes at Ambient Pressure: CO2 Capture and Selective Separation of a CO2/H-2 Mixture in Water
复制标题
环境压力下单壁碳纳米管内 CO2 水合物的形成：CO2 捕获和水中 CO2/H-2 混合物的选择性分离
DOI：
10.1021/acs.jpcc.7b12700
复制
发表时间：
2018
影响因子：
3.7
通讯作者：
Zeng Xiao Cheng
中科院分区：
文献类型：
--
作者：
Zhao Wenhui;Bai Jaeil;Francisco Joseph S.;Zeng Xiao Cheng
二氧化碳(CO2)捕获和分离是目前公认的两种缓解由于燃烧化石燃料而增加的二氧化碳排放到大气中的策略。在这里，我们展示了基于水合物的二氧化碳捕获和选择性分离的模拟结果，这两种方法都使用单壁碳纳米管(Sw-CNTs)。在常压下，观察到碳纳米管在CO2水溶液中自发生成准一维(Q1D)多边形的CO2水合物。此外，在Q1D多边形冰纳米管中观察到了CO2在H2分子上的高选择性吸附，这是因为CO2分子的势均力差(PMF)比相应水合物中的H2分子低得多。模拟结果表明，Q1D水合物的形成可以作为CO2捕集或CO2与H2分离的一种有效途径。
Carbon dioxide (CO2) capture and separation are two currently accepted strategies to mitigate increasing CO2emissions into the atmosphere due to the burning of fossil fuels. Here, we show the simulation results of hydrate-based CO2capture and selective separation from the CO2/H2mixture dissolved in water, both using single-walled carbon nanotubes (SW-CNTs). The spontaneous formation of quasi-one-dimensional (Q1D) polygonal CO2hydrates under ambient pressure was observed within SW-CNTs immersed in CO2aqueous solution. Moreover, highly selective adsorption of a CO2over a H2molecule is observed in the Q1D polygonal ice nanotube due to a much lower value of the potential mean force (PMF) difference for a CO2molecule than for a H2molecule enclosed in the corresponding hydrate. The simulation results indicate that the formation of Q1D hydrates can be an effective approach for CO2capture or for the separation of CO2from H2in the mixture.