蒸气相中笼形类沸石材料MTN单晶的合成规律

Synthesis of a clathrate compound MTN by VPT route

采用蒸气相合成法,以正丙胺作为笼形类沸石材料MTN合成的新模板剂,合成出MTN单晶。通过改变F-/Si、氟源种类、液相中胺/水、结晶温度等指标,考察了MTN的合成规律。并采用XRD、SEM、FT-IR对样品进行了物化性能表征。实验表明,在凝胶组成为(0.5~1.0)NH4F-SiO2-6.7H2O,液相组成为PrNH2/(PrNH2+H2O)(摩尔比)=16.7%~100%的反应体系中,453 K^493 K晶化反应15 d,能够合成MTN。MTN的相对结晶度分别随着正丙胺的摩尔比、氟化铵与二氧化硅的摩尔比以及晶化温度的升高而升高。合成的MTN晶体粒度达到250μm。

Single crystal MTN has been synthesized by vapor phase transport route(VPT) using n-propylamine as a new template.The synthesis conditions of single crystal MTN including compositions of reaction mixture,crystallization temperature,time,etc.were investigated.The synthesized samples were characterized by XRD,FT-IR and SEM.The experimental results showed that MTN could be well synthesized at the following conditions: crystallization temperature 453 K^493 K,crystallization time 15 d,chemical compositions of gels and liquid reaction mixtures(0.5~1.0) NH4F-SiO26.7H2O,n-propylamine/(n-propylamine+H2O) 16.7%~100%(mol ratio) respectively.The increase in the relative crystallinity of MTN was in proportion to the increase in molar percent of npropylamine,mole ratio of NH4F/ SiO2,crystallization temperature respectively.The particle size of the synthesized single crystal MTN was up to 250 μm.