新气相超稳法工业生产的高稳定性分子筛结构与性能研究

RESEARCH ON STRUCTURE AND PERFORMANCE OF HIGH STABILIZED ZEOLITES MANUFACTURED BY THE NEW GAS-PHASE SUPER STABLIZATION METHOD

为了提高催化裂化催化剂的活性组元分子筛的稳定性和活性,通过改变分子筛阳离子交换及气相超稳改性的程度,设计并且工业制备5种不同晶胞大小的高稳定性分子筛HSZ-1,HSZ-2,HSZ-3,HSZ-4,HSZ-5,采用X射线衍射、N 2吸附-脱附及傅里叶变换红外光谱等方法对其结构与性能进行分析表征。结果表明:所开发的HSZ系列分子筛具有结晶度高、比表面积大以及热稳定性和水热稳定性高的特点;并且,随着分子筛超稳程度的提高,分子筛的晶胞常数减小、SiO 2含量升高、总酸量降低、B酸与L酸酸量比值降低、小笼羟基减少、末端硅羟基增多,但是,不同超稳程度的分子筛的大笼羟基均保持完好的结构。另外,HSZ系列分子筛均含有骨架四配位铝及非骨架六配位铝物种,超稳程度的提高使得非骨架铝含量增加;超稳程度最高的HSZ-1分子筛除具有4种Si配位状态以外,还有Si碎片存在。

In order to improve the stability and activity of zeolites,the active component of FCC catalyst,five kinds of high stabilized zeolites HSZ-1,HSZ-2,HSZ-3,HSZ-4,HSZ-5 with different cell sizes were designed and manufactured by changing the degree of cation exchange and gas phase super stablization of zeolites.The structure and performance of the five kinds of high stabilized zeolites were analyzed by X-ray diffraction,N 2 adsorption desorption and Fourier transform infrared spectroscopy techniques.The results showed that the developed high stabilized zeolites possessed the properties of high crystallinity,large specific surface area,high thermal stability and hydrothermal stability.Moreover,with the increase of the degree of super stable modification of zeolites,the cell constant of zeolites decreased,the content of SiO 2 increased,the total acid quantity and the ratio of B L ratio decreased,the amount of small cage hydroxyl decreased,the amount of terminal silicon hydroxyl increased,however the large cage hydroxyl group of the zeolites were all well preserved.In addition,HSZ series zeolites all contained four-coordinative framework aluminum and six-coordinative extra-framework aluminum species.The increase of the degree of super stable modification increased the content of extra-framework aluminum species;in addition to the four kinds of Si coordination states,HSZ-1 zeolite with the highest hyperstability also contains Si fragments.