论文部分内容阅读
采用静态水热法合成了含有不同锌含量的锌铝磷酸盐分子筛(ZnAPO-5),利用XRD、SEM、N2-吸附、MAS-NMR及ICP-AES等方法对合成的ZnAPO-5分子筛进行了表征。研究结果表明在选定的合成条件下,可以合成出AFI结构类型的ZnAPO-5分子筛,合成的ZnAPO-5分子筛结晶度较高,具有规整的六方棱柱晶体外形,杂原子同晶取代为锌取代骨架元素铝。ZnAPO-5分子筛上的正己烷催化裂解反应活性评价结果显示在反应温度为723 K~823 K时正己烷的催化裂解呈中等反应活性,正己烷的转化率随反应温度和接触时间的增加而增加,正己烷的浓度项反应级数为1,裂解反应表观速率常数随反应温度的升高而增大,且遵从Arrhenius公式;由裂解产物分布可知,在选定的实验条件下该反应以单分子反应为主。
Zinc-aluminophosphate molecular sieves (ZnAPO-5) with different zinc contents were synthesized by static hydrothermal method. The synthesized ZnAPO-5 zeolites were characterized by XRD, SEM, N2-adsorption, MAS-NMR and ICP- Characterization. The results show that the AFI structure type ZnAPO-5 zeolite can be synthesized under the selected synthesis conditions. The synthesized ZnAPO-5 molecular sieve has higher crystallinity, regular hexagonal prism shape and heteroatom isomorphous substitution for zinc substitution Skeleton element aluminum. The results of catalytic cracking of n-hexane on ZnAPO-5 zeolite showed that the catalytic cracking of n-hexane showed moderate reactivity at the reaction temperature of 723 K to 823 K, and the conversion of n-hexane increased with the increase of reaction temperature and contact time , The concentration of n-hexane reaction order is 1, the apparent rate constant of the cleavage reaction increases with the reaction temperature, and follow the Arrhenius formula; from the distribution of the pyrolysis products, the reaction under the selected experimental conditions to single Molecular reaction-based.