考察了硅酸粉末预先与NaOH溶液混合时间及晶化时间对所制备的丝光沸石晶粒大小的影响。选取8μm丝光沸石为研究对象,研究正丁烷在丝光沸石微孔孔道内的吸附扩散。结果表明,正丁烷在Na型丝光沸石上的吸附速率较慢,在考察的160min内没有达到吸附平衡。经离子交换成氢型丝光沸石后,对正丁烷的吸附性能明显改善,2min内可以达到平衡吸附量的70%,平衡吸附量为0.70mol/kg;而再次交换为Na型丝光沸石后,其正丁烷吸附性能又恢复原状,说明丝光沸石中的Na物种是堵塞微孔孔道引起正丁烷分子在孔道内扩散受限的主要原因。
The effects of the premixed time of silicic acid powder with NaOH solution and the crystallization time on the crystal size of the synthesized mordenite were systematically investigated.Additionally,the study was conducted on the adsorption and diffusion of n-butane in the synthesized mordenite(MOR) crystals with a uniform size of about 8 μm.The results showed that the adsorption of n-butane in the parent Na-MOR zeolite was extremely slow and within 160 min the adsorption could not reach equilibrium under the applied conditions.The adsorption could be significantly improved after the parent Na-MOR zeolite transferred into its H-form,and within 2 min the adsorbed amount reach to ca 70% of its equilibrium adsorption capacity(0.70 mol/kg).However,after the NH4-MOR(precursor of H-MOR) zeolite transferred into its Na-form,the adsorption of n-butane was almost the same as that in the parent Na-MOR.It is concluded that the Na species remaining in the synthesized mordenite channels caused the blockage of MOR micropores,resulting in the limitations of molecule diffusion.