分别采用水热法和SiCl4气相法对NaY分子筛进行脱铝改性,作为载体应用于磷钨酸(PW)的原位封装过程。采用XRD、N2物理吸附、ICP-AES和SEM等手段对脱铝改性后NaY分子筛载体结构进行了表征。结果表明,两种脱铝方法在使NaY分子筛硅铝比接近5.5的情况下,水热法比SiCl4气相法脱铝样品的结晶度高、比表面积和孔容更大,微孔所占的比例更高,相同条件下用于磷钨酸的原位封装过程,能获得0.0569gPW/g载体的封装量,显著高于SiCl4气相法处理的样品。
NaY zeolite was modified by dealumination using the hydrotherm treatment and SIC14 gas phase method, respectively. The dealuminated NaY zeolite was used as carrier for the in-situ encapsulation of phosphotungstic acid. The structure of dealuminated NaY zeolite was characterized by the means of XRD diffraction, N2 physical adsorption, ICP-AES and SEM. The results showed that when Si/A1 ratio was up to 5.5, the dealuminated zeolite by the hydrotherm treatment had the higher crystallinity, larger surface areas and pore volume, higher ratio of micropore than the sample modified by SIC14 gas phase method. In the process of encapsulation of phospho-tungstic acid, the amount of encapsulation was up to 0. 0569g PW/g dealuminated NaY carrier by the hydrotherm treatment, which was much higher than that using the dealuminated zeolite by the SIC14 gas phase method as carrier.