EU-1/ZSM-5复合分子筛的合成与表征

SYNTHESIS AND CHARACTERIZATION OF EU-1/ZSM-5 COMPOSITE ZEOLITE

以四丙基氢氧化铵(TPAOH)和四丙基溴化铵(TPABr)为模板剂、EU-1为铝源,水热晶化合成EU-1/ZSM-5复合分子筛。采用XRD,SEM-EDS,N2吸附-脱附及FT-IR等手段对合成样品进行表征。结果表明:所合成的EU-1/ZSM-5复合分子筛具有与EU-1分子筛及ZSM-5分子筛混合物相同的XRD图谱,但红外谱图的谱峰均向高波数方向偏移,并产生明显的次级介孔结构;在形貌上,复合分子筛中EU-1相周边规整附晶生长着ZSM-5分子筛的纳米颗粒。EU-1/ZSM-5复合分子筛的合成条件为:m(EU-1)/m(SiO2)为1.1~1.4,n(OH-)/n(SiO2)为0.07~0.15,n(TPAOH)/n(TPABr)为(1∶9)^(5∶5),晶化时间24~72 h,晶化温度100~120℃。

EU-1/ZSM-5 composite zeolite was synthesized with organic template （TPABr and TPAOH） and EU-1 zeolite was used as aluminum source. Assynthesized sample was characterized by XRD,FT-IR and SEM-EDS. XRD results showed that EU-1 and ZSM-5 were coexisted in the composite zeolite; its pattern was similar with that of the mechanical mixture of EU-1 and ZSM-5. FT-IR spectra showed that characteristic absorption bands of the composite zeolite shifted to higher wavenumber,compared with the mechanical mixture of EU-1 and ZSM-5. N2 absorption and desorption isotherms of the sample showed that secondary mesoporous structure was observed in the composite zeolite. From the SEM images it can be seen that in composite zeolite tiny grains of nano-ZSM-5 crystal grew on the edges of EU-1 zeolite particles. EU-1/ZSM-5 composite zeolite with high crystallinity can be synthesized under the following conditions：m（EU-1）/m（Si02） is 1.1-1.4,n（OH^-）/n （SiO2） is 0. 07--0.15,n（TPAOH）/ n（TPABr） is （1 ： 9） （5 ： 5）, crystallization temperature of 100--120℃ and crystallization time of 24--72 h.