正辛烷在NaY/β复合分子筛上的吸附扩散

Adsorption and Diffusion of n-Octane on NaY/β Composite Zeolite

采用频率响应(FR)和智能重量分析(IGA)技术考察了正辛烷在NaY、Hβ、NaY/β复合分子筛,以及NaY和Hβ质量比为1的机械混合物(记为NaY+β)上的吸附和扩散。结果表明,333K下,在79.99~133.32Pa范围内,正辛烷在4种分子筛上的吸附过程为其传质过程的速控步骤,并存在2种不同的吸附过程,FR响应强度值由大到小的吸附剂顺序为NaY、NaY+β、Hβ、NaY/β;大于399.97Pa时,扩散过程是主要的传质速控步骤,扩散系数由大到小的吸附剂顺序为NaY/β、NaY+β、NaY、Hβ。正辛烷与NaY分子筛的作用力明显强于其与Hβ、NaY/β和NaY+β的作用力。

The frequency response （FR） and intelligent gravimetric analysis （IGA） techniques were applied to study adsorption and diffusion processes of n-octane on NaY zeolite, Hβ zeolite, NAY/β composite and mechanical mixture of NaY and Hβ zeolite with mass ratio of l（named NaY＋β）. On the four zeolites the adsorption of n-octane was found to he the rate-controlling step and there were two different adsorption processes at 333 K and the pressure in the range of 79.99- 133.32 Pa. Based on their response intensities from large to small, the four absorbents were in the order of NaY, NaY ＋ β, Hβ and NaY^ft. Diffusion of n-octane was the rate-controlling step under the pressure of more than 399.97 Pa, with the diffusion coefficiency descending in order of NaY/β, NaY＋β, NaY, Hβ. The interaction between n-octane and NaY zeolite was significantly stronger than that between n-octane and Hβ, NaY/β or NaY＋β.