C4烃在FAU、BEA、LTL型分子筛中吸附的蒙特卡罗研究

Monte Carlo Investigation into C4 Hydrocarbon Adsorption in FAU, BEA and LTL Zeolites

应用蒙特卡罗(MC)模拟方法研究了1,3-丁二烯、1-丁烯、正丁烷三种C4烃在FAU、BEA、LTL三种分子筛中的吸附行为.模拟分别得到了298K时这些C4烃的纯组分在分子筛中的吸附等温线、吸附质分布和吸附热.结果表明,在饱和吸附状态下这些C4烃在FAU分子筛中的吸附量最大,在BEA分子筛中的吸附量居中,在LTL分子筛中的吸附量最少.对于同一种分子筛来说,正丁烷在其中的等量吸附热最大,1-丁烯居中,1,3-丁二烯最小.对于同一种C4烃来说,它在LTL分子筛中的吸附热与在BEA分子筛中的吸附热相近,并且高于在FAU分子筛中的吸附热.还模拟了543K、2.0MPa时这些C4烃的三元混合组分在分子筛中的吸附,发现正丁烷的吸附量占的比例最大,1-丁烯居中,1,3-丁二烯最少.

The adsorption of 1,3-butadiene, 1-butylene, and n-butane in FAU, BEA, and LTL zeolites was investigated by Monte Carlo （MC） simulations. The adsorption isotherms, distribution of adsorbates, and isosteric heat of the C4 hydrocarbons in the zeolites at 298 K were obtained by simulation. The results show that the amount of C4 hydrocarbon saturated adsorption in FAU was the highest, in BEA it was the second highest, and in LTL it was the lowest. For the same zeolite, the isosteric heat of n-butane was the largest, 1-butylene the second largest, and 1,3-butadiene was the lowest. For the same C4 hydrocarbon, the isosteric heat in LTL was almost the same as that in BEA. The isosteric heat in FAU was the lowest. The adsorption of C4 hydrocarbon mixtures onto the zeolites at 543 K, 2.0 MPa was also simulated. In these mixtures the amount of n-butane adsorption was the highest, 1-butylene the second highest, and 1,3-butadiene the lowest.