苯在等级孔Y型分子筛上吸附与扩散行为研究

摘要

以不同等级孔Y型分子筛为研究对象,运用XRD、N2吸附 、NH3-TPD和Py-FTIR对其织构性质和酸性质进行表征.采用智能重量分析仪(IGA)等技术考察了苯在等级孔Y型分子筛上吸附扩散性能.结果表明,等级孔Y型分子筛在改性过程中晶型结构未发生明显变化,但改变了其孔道结构 、酸类型 、酸量及酸强度.苯分子在等级孔Y型分子筛上的传质性能主要与分子筛的孔道结构有关,等级孔Y型分子筛的孔容越大,扩散速率越快,更利于苯分子的扩散.而苯分子的饱和吸附量大小主要取决于等级孔Y型分子筛的酸中心类型及其强度.%Y zeolites with different pore structural and acid properties were studied by XRD ,N2 physical adsorption ,NH3-TPD and Py-FTIR .The adsorption and diffusion properties of benzene in hierarchical pore Y zeolites were investigated by using intelligent gravimetric analyzer (IGA) .It was found that there was no obvious change in the crystal structure of the Y zeolites in the process of modification ,while the pore structure ,acid type ,acidity and acid strength were changed .The mass transfer performance of benzene molecules in the pore level Y zeolite molecular sieve was mainly decided by pore structure .The larger of pore volume Y molecular sieve was ,the faster diffusion rate was .It was more conducive to the diffusion of benzene molecule . The amount of saturated adsorption of benzene molecule was depended on the type and intensity of acid type of Y zeolite .