【作者】 张浩； 范燕飞； 岳明波；

【Author】 Hao Zhang;Yan Fei Fan;Ming Bo Yue;School of Chemistry and Chemical Engineering,Qufu Normal University;

【机构】 曲阜师范大学化学与化工学院；

【摘要】 本文以正硅酸乙酯(TEOS)为硅源,钛酸四丁酯(TBOT)、硝酸铁、硝酸镍、硝酸铬为杂原子金属源,以三乙醇胺(TEA)为络合剂,以四乙基氢氧化铵(TPAOH)为结构导向剂,用干凝胶法通过挤压成型成功制备了含钛、铁、镍、铬的M-MFI(M=Ti、Fe、Ni、Cr)型微孔分子筛。通过XRD、FTIR、ESR、UV-vis、SEM、BET等方法对M-MFI分子筛进行表征。ESR和UV-vis结果表明金属杂原子成功进入分子筛骨架结构。XRD和FTIR结果表明,成功合成MFI型金属杂原子分子筛,通过对铁硅分子筛的不同三乙醇胺含量的研究表明,三乙醇胺量越大,分子筛尺寸越大。通过对钛硅分子筛不同含水量的结晶度研究表明,当含水量降到最小10%时,相对结晶度可达到100%。实验结果表明,通过干凝胶法,用较少量的结构导向剂TPAOH和少量的水,一步成型合成出含钛、铁、铬、镍的成型杂原子分子筛,避免传统工艺中的过滤和洗涤,降低了催化剂的生产成本,最大限度上减少了废水的产生。更多还原

【Abstract】 Shaped transition-metal-doped M-MFI zeolites were prepared by using a rapid dry-gel conversion technique from shaped extrudates with metal-occluded zeolite seed sol as a director agent.The metal（Ti,Fe,Cr,Ni）-occluded zeolites seed sols were prepared at a high tetrapropylammonium hydroxide（TPAOH）/SiO₂ molar ratio or with the addition of triethanolamine to keep a good dispersion of the transition metal in the seed sols.The silica gel and zeolites seed sols were mixed well and extruded into cylindrical-shaped extrudates with a diameter of 2 mm.The metal-occluded seed sol promoted the distribution of the metal and provided crystal nuclei for rapid crystallization.In this method,the total molar ratio of TPA0H/SiO₂ decreased to 0.1-0.175,which lowers the cost of preparing the zeolites.更多还原