摘要
通过在ＳＡＰＯ－５分子筛的前身体中加入不同含量不同形式的钯盐方式，直接合成出了分子筛上担载贵金属的双功能催化剂，Ｘ光衍射（ＸＲＤ）结果表明把的加入并不影响ＳＡＰＯ－５分子筛的生成，但降低了分子筛结晶度。当把以碱性介质加入反应物时，使产物中有少量ＳＡＰＯ－３４伴生，由ＭＡＳＮＭＲ实验结果可见，反应物中把的加入抑制了硅进入分子筛骨架，使骨架铝配位环境更加对称，并使三乙胺模板分解，改变了其在分子筛中的存在状态。从而导致分子筛结晶度的降低．
SAPO-5 molecular sicve bas been synthesized by hydrothermal method．Palladium is supported on it by adding Pd salt solution （Pd（NH_3）_4Cl_2 and H_2PdCl_4）into themixture gel of SAPO-5 before crystallizzation in order to obtain bifunctional catalyst。The result of X-ray diffraction reveals that the introduction of palladium salt in themixture gel does not deprcss the formation of SAPO-5． However,when palladium isadded in the form of Pd（NH_3）_4Cl_2， there intergrows a little SAPO-34 in the product。MAS NMR results show that the addition of palladium obstructs silicon to enter theframework and thus makes a more symmetrical coordination environment of alumini－um and Causes partialy decomposition and polymeriZation of the template in SAPO-5.The reaction of the template during crystallization differs with the palladium precur-sors .^(31)P MAS NMR result shows that the addition of palladium salt in the mixture gelhas little influenee on the coordination environment of phosphorus in the framework.
出处
《波谱学杂志》
CAS
CSCD
1994年第2期157-163,共7页
Chinese Journal of Magnetic Resonance
关键词
SAPO-5
分子筛
钯
NMR
Palladium addition； SAPO-5 molecular sieve ； MAs NMR
