MD模拟研究含金属离子的MCM41对水的吸附

ADSORPTION STUDY OF WATER IN METAL ION CONTAINED MCM41 BY MD SIMULATIONS

本文采用MD模拟研究了分别含有Al3+, Cu2+和La3+等金属离子的中孔分子筛MCM41在较大温度范围内对水的吸附情况,通过考察水分子在孔内的局部平均密度分布,发现含有Al3+和La3+的MCM41对水有较好的吸附性能,表现在吸附量提高和脱附温度降低。我们认为其吸附性能提高的主要原因在于引入金属离子导致了壁面极性增加,增加了吸附表面的活性点,改变了壁面分子结构等几个方面。

MD simulations were carried out to study adsorption behavior of water in wide range of temperature in MCM41 that each contained a kind of ion such as A13+, Cu2+, and La3+. By observing the local average density distribution of water, the A13+-contained and La3+-contained MCM-41 performed better owing to their higher adsorption amount and lower desorption temperature. We contend that the main reasons for the improvement may lie in polarity of the MCM41 pore-wall increasing, introducing active sites into surface, molecular structure changing, and so on.